1.
Wine
–
Wine is an alcoholic beverage made from fermented grapes. These grapes are generally Vitis vinifera, or a hybrid with Vitis labrusca or Vitis rupestris, grapes are fermented without the addition of sugars, acids, enzymes, water, or other nutrients. Yeast consumes the sugar in the grapes and converts it to ethanol, different varieties of grapes and strains of yeasts produce different styles of wine. These variations result from the interactions between the biochemical development of the grape, the reactions involved in fermentation, the terroir. Many countries enact legal appellations intended to define styles and qualities of wine and these typically restrict the geographical origin and permitted varieties of grapes, as well as other aspects of wine production. There are also made from fermenting other fruits or cereals. Wines made from other than grapes include rice wine and various fruit wines such as those made from plums or cherries. Some well known examples are hard cider from apples, perry from pears, pomegranate wine, Wine has been produced for thousands of years. The earliest known traces of wine from Georgia in Eurasia where 8000-year-old wine jars were found and in Iran with 7, the earliest known winery is the 6, 100-year-old Areni-1 winery Armenia. Wine reached the Balkans by 4500 BC and was consumed and celebrated in ancient Greece, Thrace, throughout history, wine has been consumed for its intoxicating effects, which are evident after the normal serving size of five ounces. Wine has long played an important role in religion, the earliest chemically attested grape wine was discovered at Hajji Firuz in the northwestern Zagros Mountains dating back to 5400 BC. The earliest evidence of a fermented drink was found in Georgia, where wine residue inside ceramic jars dates from 6000 BC. The earliest evidence of a production facility is the Areni-1 winery in Armenia and is at least 6100 years old, presumably. A2003 report by archaeologists indicates a possibility that grapes were mixed with rice to produce mixed fermented beverages in China in the years of the seventh millennium BC. Pottery jars from the Neolithic site of Jiahu, Henan, contained traces of tartaric acid, however, other fruits indigenous to the region, such as hawthorn, cannot be ruled out. The spread of wine culture westwards was most probably due to the Phoenicians who spread outward from a base of city-states along the Lebanese, Syrian, the wines of Byblos were exported to Egypt during the Old Kingdom and then throughout the Mediterranean. Evidence includes two Phoenician shipwrecks from 750 BC discovered by Robert Ballard, whose cargo of wine was still intact. As the first great traders in wine, the Phoenicians seem to have protected it from oxidation with a layer of oil, followed by a seal of pinewood and resin
2.
Wine color
–
The color of wine is one of the most easily recognizable characteristics of wines. Color is also an element in wine tasting since heavy wines generally have a deeper color, the accessory traditionally used to judge the wine color was the tastevin, a shallow cup allowing one to see the color of the liquid in the dim light of a cellar. The color is an element in the classification of wines, the color of the wine mainly depends on the color of the drupe of the grape variety. The Teinturier grape is an exception in that it also has a pigmented pulp, the blending of two or more varieties of grapes can explain the color of certain wines, like the addition of Rubired to intensify redness. Red drupe grapes can produce white wine if they are quickly pressed, the color is mainly due to plant pigments, notably phenolic compounds. The color depends on the presence of acids in the wine, the use of a wooden barrel in aging also affects the color of the wine. The color of a wine can be due to co-pigmentation of anthocyanidins with other non-pigmented flavonoids or natural phenols. Rosé wine is made by the practice of saignée or by blending a white wine with a red wine, the presence of a complex mixture of anthocyanins and procyanidins can increase the stability of color in wine. As it ages, the wine undergoes chemical reactions involving acetaldehyde of its pigments molecules. The newly formed molecules are stable to the effect of pH or sulfite bleaching. The new compounds include pyranoanthocyanins like vitisins, pinotins and portosins, malvidin glucoside-ethyl-catechin is a flavanol-anthocyanin adduct. Flavanol-anthocyanin adducts are formed during wine ageing through reactions between anthocyanins and tannins present in grape, with yeast metabolites such as acetaldehyde, acetaldehyde-induced reactions yield ethyl-linked species such as malvidin glucoside-ethyl-catechin. This compound has a better stability at pH5.5 than malvidin-3O-glucoside. When the pH was increased from 2.2 to 5.5, the exposure of wine to oxygen in limited quantities can be beneficial to the wine. Castavinols are another class of colorless molecules derived from colored anthocyanin pigments, in model solutions, colorless compounds, such as catechin, can give rise to new types of pigments. The first step is the formation of colorless dimeric compounds consisting of two units linked by carboxy-methine bridge. This is followed by the formation of xanthylium salt yellowish pigments and their ethylesters, resulting from the dehydration of the colorless dimers, the loss of a water molecule takes place between two A ring hydroxyl groups of the colorless dimers. The main colors of wine are, Gray, as in vin gris, orange, as in orange wine, a white wine that has spent some time in contact with its skin, giving it a slightly darker hue
3.
Juice
–
Juice is a beverage made from the extraction or pressing out of the natural liquid contained in fruit and vegetables. It can also refer to liquids that are flavored with these or other food sources such as meat. Juice is commonly consumed as a beverage or used as an ingredient or flavoring in foods or other beverages, juice emerged as a popular beverage choice after the development of pasteurization methods allowed for its preservation without using fermentation. The Food and Agriculture Organization of the United Nations estimated the world production of citrus fruit juices to be 12,840,318 tonnes in 2012. The largest fruit juice consumers are New Zealand and Colombia, fruit juice consumption on average increased with country income level. The word juice comes from Old French in about 1300, it developed from the Old French words jus, juis, jouis, the Old French jus juice, sap, liquid. From Latin ius broth, sauce, juice, soup, from PIE root *yeue- to blend, the use of the word juice to meanthe watery part of fruits or vegetables was first recorded in the early 14th century. Since the 19th century, the juice has also been used in a figurative sense. Today, au jus refers to meat served along with its own juice, juice is prepared by mechanically squeezing or macerating fruit or vegetable flesh without the application of heat or solvents. For example, orange juice is the extract of the fruit of the orange tree. Juice may be prepared in the home from fresh fruit and vegetables using a variety of hand or electric juicers, many commercial juices are filtered to remove fiber or pulp, but high-pulp fresh orange juice is a popular beverage. Additives are put in some juices, such as sugar and artificial flavours, common methods for preservation and processing of fruit juices include canning, pasteurization, concentrating, freezing, evaporation and spray drying. After the fruits are picked and washed, the juice is extracted by one of two automated methods. In the first method, two cups with sharp metal tubes on the bottom cup come together, removing the peel. The juice of the fruit then escapes through small holes in the tube, the peels can then be used further, and are washed to remove oils, which are reclaimed later for usage. The second method requires the fruits to be cut in half before being subjected to reamers, which extract the juice. After the juice is filtered, it may be concentrated in evaporators, Juices are concentrated by heating under a vacuum to remove water, and then cooling to around 13 degrees Celsius. About two thirds of the water in a juice is removed, the juice is then later reconstituted, in which the concentrate is mixed with water and other factors to return any lost flavor from the concentrating process
4.
Anthocyanin
–
Anthocyanins are water-soluble vacuolar pigments that may appear red, purple, or blue depending on the pH. They belong to a parent class of molecules called flavonoids synthesized via the pathway, they are odorless but flavorful. Anthocyanins occur in all tissues of plants, including leaves, stems, roots, flowers. Anthoxanthins are clear, white to yellow counterparts of anthocyanins occurring in plants, anthocyanins are derived from anthocyanidins by adding sugars. Anthocyanins have an antioxidant role in plants against reactive oxygen species caused by abiotic stresses, such as overexposure to ultraviolet light, tomato plants protect against cold stress with anthocyanins countering reactive oxygen species, leading to a lower rate of cell death in leaves. Anthocyanins are considered secondary metabolites as an additive with E number E163, they are approved for use as a food additive in the EU, Australia. Although anthocyanins have antioxidant properties in vitro, this antioxidant effect is not conserved after the plant is consumed, as interpreted by the Linus Pauling Institute and European Food Safety Authority, dietary anthocyanins and other flavonoids have little or no direct antioxidant food value following digestion. The absorbance pattern responsible for the red color of anthocyanins may be complementary to that of green chlorophyll in photosynthetically active tissues such as young Quercus coccifera leaves and it may protect the leaves from attacks by plant eaters that may be attracted by green color. Anthocyanins are found in the vacuole, mostly in flowers and fruits but also in leaves, stems. In these parts, they are predominantly in outer cell layers such as the epidermis. Most frequently occurring in nature are the glycosides of cyanidin, delphinidin, malvidin, pelargonidin, peonidin, roughly 2% of all hydrocarbons fixed in photosynthesis are converted into flavonoids and their derivatives such as the anthocyanins. Not all land plants contain anthocyanin, in the Caryophyllales, they are replaced by betalains, anthocyanins and betalains have never been found in the same plant. Sometimes bred purposely for high anthocyanin quantities, ornamental plants such as sweet peppers may have unusual culinary, anthocyanins occur in the flowers of many plants, such as the famously blue poppies of some Meconopsis species and cultivars. Red-fleshed peaches and apples contain anthocyanins, anthocyanins are less abundant in banana, asparagus, pea, fennel, pear, and potato, and may be totally absent in certain cultivars of green gooseberries. The highest recorded amount appears to be specifically in the coat of black soybean containing around 2 g per 100 g, in purple corn kernels and husks. Due to critical differences in origin, preparation and extraction methods determining anthocyanin content. The variety known as Indigo Rose became commercially available to the agricultural industry, investing tomatoes with high anthocyanin content doubles their shelf-life and inhibits growth of a post-harvest mold pathogen, Botrytis cinerea. Tomatoes have also been modified with transcription factors from snapdragons to produce high levels of anthocyanins in the fruits
5.
Teinturier
–
In most cases, anthocyanin pigments are confined to the outer skin tissue only, and the squeezed grape juice of most dark-skinned grape varieties is clear. The red color of red wine comes from anthocyanins extracted from the macerated skins, teinturier varieties, while containing a lot of color, usually make special wines, perhaps due to a higher level of tannins, compounds structurally related to the anthocyanins. Many winemakers blend small volumes of teinturier juices into their wines, to boost the colour, Alicante Bouschet Alicante Ganzi Chambourcin Dunkelfelder Gamay de Bouze Grand Noir de la Calmette Morrastel Bouschet Petit Bouschet Royalty Rubired Salvador Saperavi
6.
Winemaker
–
A winemaker or vintner is a person engaged in winemaking. Winemakers can also be referred to as oenologists as they study oenology – the science of wine, a vintner is a wine merchant. In some modern use, particularly in American English, the term is used as a synonym for winemaker. The term started to be used in Middle English, when it superseded the earlier term vinter, a vigneron is someone who cultivates a vineyard for winemaking. The word connotes or emphasizes the role that vineyard placement. It is also used when referring to a winemaker from France, vincent of Saragossa is the patron saint of vignerons. A négociant is the French term for a merchant who assembles the produce of smaller growers and winemakers. Négociants buy everything from grapes to grape must to wines in various states of completion, in the case of grapes or must, the négociant performs virtually all the winemaking. If it buys already fermented wine in barrels or en-vrac—basically in bulk containers, it may age the wine further, blend in other wines or simply bottle, the result is sold under the name of the négociant, not the name of the original grape or wine producer. Currently, one of the largest Negociants in the United States and, some négociants have a recognizable house style. It was too expensive for growers to purchase the wine presses, owning only a small portion of a particular high-quality single vineyard meant that a grower often had insufficient wine from a parcel to vinify on its own. Under French inheritance laws, vineyard holdings were split until offspring owned no more than a single row of grapes. Many négociants are also vineyard owners in their own right, in Burgundy for instance, négociants as Bouchard Père et Fils and Faiveley are among the largest owners of vineyards. Oenology Vignerons indépendants de France Viticulture Winemaking cooperative Winery
7.
Must
–
Must is freshly pressed fruit juice that contains the skins, seeds, and stems of the fruit. The solid portion of the must is called pomace, it makes up 7–23% of the total weight of the must. Making must is the first step in winemaking, because of its high glucose content, typically between 10 and 15%, must is also used as a sweetener in a variety of cuisines. Unlike commercially sold grape juice, which is filtered and pasteurized, must is thick with particulate matter, opaque, the length of time that the pomace stays in the juice is critical for the final character of the wine. When the winemaker judges the time to be right, the juice is drained off the pomace, yeast is added to the juice to begin the fermentation, while the pomace is often returned to the vineyard or orchard to be used as fertilizer. A portion of selected unfermented must may be kept as Süssreserve, some winemakers create a second batch of wine from the used pomace by adding a quantity of water equivalent to the juice removed, letting the mixture sit for 24 hours, and draining off the liquid. This wine may be used as a drink for the employees of the winemaker or as a basis for some pomace brandies, grappa, however, by law, must be produced only from the pomace solids, with no water added. Both the acetification and maturation take place in precious sessile oak, chestnut, oak, mulberry, the minimum maturation time is 60 days and after this period a group of expert technicians test analytic and organoleptic resulting product. This term is used by meadmakers for the unfermented honey-water mixture that becomes mead. The analogous term in beer brewing is wort, in ancient Greece, condensed must by boiling, was called siraios and was used as a sweeteners in the kitchen, in various recipes, and also as a syrup over tiganitai. From the Greeks, the Romans in ancient Rome also used the condensed must in cooking, must was boiled in lead or bronze kettles into a milder concentrate called defrutum or a stronger concentrate called sapa. It was often used as an agent and preservative, especially in fruit dishes. The Moustokoúloura, or must cookies are also popular Greek cookies, which are based on a dough made by kneading flour, olive oil, spice. They are made in shapes and sizes, and they are dark brown in color because of the must. The term petimezi is a Hellenized word of the Armenian/Trebizond term petmez and this theory has been thoroughly criticized by, among others, pharmacologist John Scarborough. Aquinas himself declared that it is forbidden to offer fresh must in the chalice, because this is unbecoming owing to the impurity of the must, but he added that in case of necessity it may be done. Aquinas himself declared, Must has already the species of wine, for its sweetness indicates fermentation and it is forbidden to offer must in the chalice, as soon as it has been squeezed from the grape, since this is unbecoming owing to the impurity of the must. But in case of necessity it may be done, for it is said by the same Pope Julius, in the passage quoted in the argument, If necessary, permission can be granted habitually, for as long as the situation that occasioned the granting of permission continues
8.
Winemaking
–
Winemaking or vinification, is the production of wine, starting with selection of the grapes or other produce and ending with bottling the finished wine. Although most wine is made from grapes, it may also be made from fruits or plants. Mead is a wine that is made with honey being the primary ingredient after water, Winemaking can be divided into two general categories, still wine production and sparkling wine production. The science of wine and winemaking is known as oenology, a person who makes wine is traditionally called a winemaker or vintner. After the harvest, the grapes are taken into a winery, at this stage red wine making diverges from white wine making. Red wine is made from the must of red or black grapes and fermentation occurs together with the grape skins, white wine is made by fermenting juice which is made by pressing crushed grapes to extract a juice, the skins are removed and play no further role. Occasionally white wine is made from red grapes, this is done by extracting their juice with minimal contact with the grapes skins. Rosé wines are made from red grapes where the juice is allowed to stay in contact with the dark skins long enough to pick up a pinkish color or by blending red wine with white wine. White and rosé wines extract little of the contained in the skins. To start primary fermentation yeast may be added to the must for red wine or may occur naturally as ambient yeast on the grapes or in the air, yeast may be added to the juice for white wine. During this fermentation, which takes between one and two weeks, the yeast converts most of the sugars in the grape juice into ethanol. The carbon dioxide is lost to the atmosphere, after the primary fermentation of red grapes the free run wine is pumped off into tanks and the skins are pressed to extract the remaining juice and wine. The press wine is blended with the free run wine at the winemakers discretion, the wine is kept warm and the remaining sugars are converted into alcohol and carbon dioxide. The next process in the making of red wine is malo-lactic conversion and this is a bacterial process which converts crisp, green apple malic acid to soft, creamy lactic acid softening the taste of the wine. Red wine is transferred to oak barrels to mature for a period of weeks or months. The wine must be settled or clarified and adjustments made prior to bottling, the time from harvest to drinking can vary from a few months for Beaujolais nouveau wines to over twenty years for wine of good structure with high levels of acid, tannin or sugar. However, only about 10% of all red and 5% of white wine will taste better after five years than it will after just one year. Depending on the quality of grape and the wine style
9.
Stainless steel
–
In metallurgy, stainless steel, also known as inox steel or inox from French inoxydable, is a steel alloy with a minimum of 10. 5% chromium content by mass. Stainless steel is notable for its resistance, and it is widely used for food handling. Stainless steel does not readily corrode, rust or stain with water as ordinary steel does, however, it is not fully stain-proof in low-oxygen, high-salinity, or poor air-circulation environments. There are various grades and surface finishes of stainless steel to suit the environment the alloy must endure, Stainless steel is used where both the properties of steel and corrosion resistance are required. Stainless steel differs from carbon steel by the amount of chromium present, unprotected carbon steel rusts readily when exposed to air and moisture. This iron oxide film is active and accelerates corrosion by making it easier for more iron oxide to form, since iron oxide has lower density than steel, the film expands and tends to flake and fall away. In comparison, stainless steels contain sufficient chromium to undergo passivation and this layer prevents further corrosion by blocking oxygen diffusion to the steel surface and stops corrosion from spreading into the bulk of the metal. Passivation occurs only if the proportion of chromium is high enough, Stainless steel’s resistance to corrosion and staining, low maintenance, and familiar lustre make it an ideal material for many applications. Storage tanks and tankers used to transport orange juice and other food are made of stainless steel. This also influences its use in kitchens and food processing plants, as it can be steam-cleaned and sterilized. High oxidation resistance in air at ambient temperature is achieved with addition of a minimum of 13% chromium. The chromium forms a layer of chromium oxide when exposed to oxygen. The layer is too thin to be visible, and the metal remains lustrous, the layer is impervious to water and air, protecting the metal beneath, and this layer quickly reforms when the surface is scratched. This phenomenon is called passivation and is seen in other metals, corrosion resistance can be adversely affected if the component is used in a non-oxygenated environment, a typical example being underwater keel bolts buried in timber. When stainless steel parts such as nuts and bolts are forced together, when forcibly disassembled, the welded material may be torn and pitted, a destructive effect known as galling. Galling can be avoided by the use of materials for the parts forced together, for example bronze and stainless steel. However, two different alloys electrically connected in a humid, even mildly acidic environment may act as a voltaic pile, nitronic alloys, made by selective alloying with manganese and nitrogen, may have a reduced tendency to gall. Additionally, threaded joints may be lubricated to provide a film between the two parts and prevent galling, low-temperature carburizing is another option that virtually eliminates galling and allows the use of similar materials without the risk of corrosion and the need for lubrication
10.
Redox
–
Redox is a chemical reaction in which the oxidation states of atoms are changed. Any such reaction involves both a process and a complementary oxidation process, two key concepts involved with electron transfer processes. Redox reactions include all chemical reactions in which atoms have their oxidation state changed, in general, the chemical species from which the electron is stripped is said to have been oxidized, while the chemical species to which the electron is added is said to have been reduced. It can be explained in terms, Oxidation is the loss of electrons or an increase in oxidation state by a molecule, atom. Reduction is the gain of electrons or a decrease in state by a molecule, atom. As an example, during the combustion of wood, oxygen from the air is reduced, the reaction can occur relatively slowly, as in the case of rust, or more quickly, as in the case of fire. Redox is a portmanteau of reduction and oxidation, the word oxidation originally implied reaction with oxygen to form an oxide, since dioxygen was historically the first recognized oxidizing agent. Later, the term was expanded to encompass oxygen-like substances that accomplished parallel chemical reactions, ultimately, the meaning was generalized to include all processes involving loss of electrons. The word reduction originally referred to the loss in weight upon heating a metallic ore such as an oxide to extract the metal. In other words, ore was reduced to metal, antoine Lavoisier showed that this loss of weight was due to the loss of oxygen as a gas. Later, scientists realized that the atom gains electrons in this process. The meaning of reduction then became generalized to all processes involving gain of electrons. Even though reduction seems counter-intuitive when speaking of the gain of electrons, it help to think of reduction as the loss of oxygen. Since electrons are charged, it is also helpful to think of this as reduction in electrical charge. The electrochemist John Bockris has used the words electronation and deelectronation to describe reduction and oxidation processes respectively when they occur at electrodes and these words are analogous to protonation and deprotonation, but they have not been widely adopted by chemists. The term hydrogenation could be used instead of reduction, since hydrogen is the agent in a large number of reactions. But, unlike oxidation, which has been generalized beyond its root element, the word redox was first used in 1928. The processes of oxidation and reduction occur simultaneously and cannot happen independently of one another, the oxidation alone and the reduction alone are each called a half-reaction, because two half-reactions always occur together to form a whole reaction
11.
Fermentation in winemaking
–
The process of fermentation in winemaking turns grape juice into an alcoholic beverage. During fermentation, yeasts transform sugars present in the juice into ethanol, in winemaking, the temperature and speed of fermentation are important considerations as well as the levels of oxygen present in the must at the start of the fermentation. The natural occurrence of fermentation means it was probably first observed long ago by humans, the Latin fervere means, literally, to boil. The most common genera of yeasts found in winemaking include Candida, Klöckera/Hanseniaspora, Metschnikowiaceae, Pichia. Wild yeasts can produce high-quality, unique-flavored wines, however, they are unpredictable and may introduce less desirable traits to the wine. The cultured yeasts most commonly used in winemaking belong to the Saccharomyces cerevisiae species, the use of different strains of yeasts is a major contributor to the diversity of wine, even among the same grape variety. Alternative, non-Saccharomyces cerevisiae, yeasts are being used more prevalently in the industry to add complexity to wine. After a winery has been in operation for a number of years, the use of active dry yeasts reduces the variety of strains that appear in spontaneous fermentation by outcompeting those strains that are naturally present. The addition of cultured yeast normally occurs with the yeast first in a dried or inactive state and is reactivated in warm water or diluted grape juice prior to being added to the must. To thrive and be active in fermentation, the yeast needs access to a supply of carbon, nitrogen, sulfur, phosphorus as well as access to various vitamins. These components are present in the grape must but their amount may be corrected by adding nutrients to the wine. Newly formulated time-release nutrients, specifically manufactured for wine fermentations, offer the most advantageous conditions for yeast. Oxygen is needed as well, but in making, the risk of oxidation. During this process, the carbon atom is released in the form of carbon dioxide with the remaining components becoming acetaldehyde. The absence of oxygen in this process allows the acetaldehyde to be eventually converted, by reduction. During the conversion of acetaldehyde, an amount is converted, by oxidation, to acetic acid which, in excess. After the yeast has exhausted its life cycle, they fall to the bottom of the tank as sediment known as lees. The metabolism of amino acids and breakdown of sugars by yeasts has the effect of creating other biochemical compounds that can contribute to the flavor and aroma of wine
12.
Enzyme
–
Enzymes /ˈɛnzaɪmz/ are macromolecular biological catalysts. Enzymes accelerate, or catalyze, chemical reactions, the molecules at the beginning of the process upon which enzymes may act are called substrates and the enzyme converts these into different molecules, called products. Almost all metabolic processes in the cell need enzymes in order to occur at rates fast enough to sustain life, the set of enzymes made in a cell determines which metabolic pathways occur in that cell. The study of enzymes is called enzymology, enzymes are known to catalyze more than 5,000 biochemical reaction types. Most enzymes are proteins, although a few are catalytic RNA molecules, enzymes specificity comes from their unique three-dimensional structures. Like all catalysts, enzymes increase the rate of a reaction by lowering its activation energy, some enzymes can make their conversion of substrate to product occur many millions of times faster. An extreme example is orotidine 5-phosphate decarboxylase, which allows a reaction that would take millions of years to occur in milliseconds. Chemically, enzymes are like any catalyst and are not consumed in chemical reactions, enzymes differ from most other catalysts by being much more specific. Enzyme activity can be affected by other molecules, inhibitors are molecules that decrease enzyme activity, many drugs and poisons are enzyme inhibitors. An enzymes activity decreases markedly outside its optimal temperature and pH, some enzymes are used commercially, for example, in the synthesis of antibiotics. French chemist Anselme Payen was the first to discover an enzyme, diastase and he wrote that alcoholic fermentation is an act correlated with the life and organization of the yeast cells, not with the death or putrefaction of the cells. In 1877, German physiologist Wilhelm Kühne first used the term enzyme, the word enzyme was used later to refer to nonliving substances such as pepsin, and the word ferment was used to refer to chemical activity produced by living organisms. Eduard Buchner submitted his first paper on the study of yeast extracts in 1897, in a series of experiments at the University of Berlin, he found that sugar was fermented by yeast extracts even when there were no living yeast cells in the mixture. He named the enzyme that brought about the fermentation of sucrose zymase, in 1907, he received the Nobel Prize in Chemistry for his discovery of cell-free fermentation. Following Buchners example, enzymes are usually named according to the reaction they carry out, the biochemical identity of enzymes was still unknown in the early 1900s. Sumner showed that the enzyme urease was a protein and crystallized it. These three scientists were awarded the 1946 Nobel Prize in Chemistry, the discovery that enzymes could be crystallized eventually allowed their structures to be solved by x-ray crystallography. This high-resolution structure of lysozyme marked the beginning of the field of structural biology, an enzymes name is often derived from its substrate or the chemical reaction it catalyzes, with the word ending in -ase
13.
Phenolic content in wine
–
These compounds include phenolic acids, stilbenoids, flavonols, dihydroflavonols, anthocyanins, flavanol monomers and flavanol polymers. This large group of natural phenols can be separated into two categories, flavonoids and non-flavonoids. Flavonoids include the anthocyanins and tannins which contribute to the color, the non-flavonoids include the stilbenoids such as resveratrol and phenolic acids such as benzoic, caffeic and cinnamic acids. The natural phenols are not evenly distributed within the fruit, phenolic acids are largely present in the pulp, anthocyanins and stilbenoids in the skin, and other phenols in the skin and the seeds. During the growth cycle of the grapevine, sunlight will increase the concentration of phenolics in the grape berries, the proportion of the different phenols in any one wine will therefore vary according to the type of vinification. Red wines will also have the phenols found in white wines, anthocyanins react with catechins, proanthocyanidins and other wine components during wine aging to form new polymeric pigments resulting in a modification of the wine color and a lower astringency. Average total polyphenol content measured by the Folin method is 216 mg/100 ml for red wine and 32 mg/100 ml for white wine, the content of phenols in rosé wine is intermediate between that in red and white wines. In winemaking, the process of maceration or skin contact is used to increase the concentration of phenols in wine, phenolic acids are found in the pulp or juice of the wine and can be commonly found in white wines which usually do not go through a maceration period. The process of oak aging can also introduce phenolic compounds into wine, most wine phenols are classified as secondary metabolites and were not thought to be active in the primary metabolism and function of the grapevine. However, there is evidence that in some plants flavonoids play a role as regulators of auxin transport. They are water-soluble and are secreted into the vacuole of the grapevine as glycosides. Vitis vinifera produces many phenolic compounds, there is a varietal effect on the relative composition. In red wine, up to 90% of the phenolic content falls under the classification of flavonoids. These phenols, mainly derived from the stems, seeds and skins are often leached out of the grape during the period of winemaking. The amount of phenols leached is known as extraction and these compounds contribute to the astringency, color and mouthfeel of the wine. In white wines the number of flavonoids is reduced due to the contact with the skins that they receive during winemaking. There is on-going study into the benefits of wine derived from the antioxidant. Within the flavonoid category is a known as flavonols, which includes the yellow pigment - quercetin
14.
Alcohol
–
In chemistry, an alcohol is any organic compound in which the hydroxyl functional group is bound to a saturated carbon atom. The term alcohol originally referred to the alcohol ethanol, the predominant alcohol in alcoholic beverages. The suffix -ol in non-systematic names also typically indicates that the substance includes a functional group and, so. But many substances, particularly sugars contain hydroxyl functional groups without using the suffix, an important class of alcohols, of which methanol and ethanol are the simplest members is the saturated straight chain alcohols, the general formula for which is CnH2n+1OH. The word alcohol is from the Arabic kohl, a used as an eyeliner. Al- is the Arabic definite article, equivalent to the in English, alcohol was originally used for the very fine powder produced by the sublimation of the natural mineral stibnite to form antimony trisulfide Sb 2S3, hence the essence or spirit of this substance. It was used as an antiseptic, eyeliner, and cosmetic, the meaning of alcohol was extended to distilled substances in general, and then narrowed to ethanol, when spirits as a synonym for hard liquor. Bartholomew Traheron, in his 1543 translation of John of Vigo, Vigo wrote, the barbarous auctours use alcohol, or alcofoll, for moost fine poudre. The 1657 Lexicon Chymicum, by William Johnson glosses the word as antimonium sive stibium, by extension, the word came to refer to any fluid obtained by distillation, including alcohol of wine, the distilled essence of wine. Libavius in Alchymia refers to vini alcohol vel vinum alcalisatum, Johnson glosses alcohol vini as quando omnis superfluitas vini a vino separatur, ita ut accensum ardeat donec totum consumatur, nihilque fæcum aut phlegmatis in fundo remaneat. The words meaning became restricted to spirit of wine in the 18th century and was extended to the class of substances so-called as alcohols in modern chemistry after 1850, the term ethanol was invented 1892, based on combining the word ethane with ol the last part of alcohol. In the IUPAC system, in naming simple alcohols, the name of the alkane chain loses the terminal e and adds ol, e. g. as in methanol and ethanol. When necessary, the position of the group is indicated by a number between the alkane name and the ol, propan-1-ol for CH 3CH 2CH 2OH, propan-2-ol for CH 3CHCH3. If a higher priority group is present, then the prefix hydroxy is used, in other less formal contexts, an alcohol is often called with the name of the corresponding alkyl group followed by the word alcohol, e. g. methyl alcohol, ethyl alcohol. Propyl alcohol may be n-propyl alcohol or isopropyl alcohol, depending on whether the group is bonded to the end or middle carbon on the straight propane chain. As described under systematic naming, if another group on the molecule takes priority, Alcohols are then classified into primary, secondary, and tertiary, based upon the number of carbon atoms connected to the carbon atom that bears the hydroxyl functional group. The primary alcohols have general formulas RCH2OH, the simplest primary alcohol is methanol, for which R=H, and the next is ethanol, for which R=CH3, the methyl group. Secondary alcohols are those of the form RRCHOH, the simplest of which is 2-propanol, for the tertiary alcohols the general form is RRRCOH
15.
Yeast in winemaking
–
The role of yeast in winemaking is the most important element that distinguishes wine from grape juice. In the absence of oxygen, yeast converts the sugars of wine grapes into alcohol, the more sugars in the grapes, the higher the potential alcohol level of the wine if the yeast are allowed to carry out fermentation to dryness. Sometimes winemakers will stop fermentation early in order to some residual sugars. If fermentation is stopped, such as when the yeasts become exhausted of available nutrients. Despite its widespread use which often includes deliberate inoculation from cultured stock, grapes brought in from harvest are usually teeming with a variety of wild yeast from the Kloeckera and Candida genera. These yeasts often begin the process almost as soon as the grapes are picked when the weight of the clusters in the harvest bins begin to crush the grapes. For most of the history of wine, winemakers did not know the mechanism that somehow converted sugary grape juice into alcoholic wine and this history is preserved in the etymology of the word yeast itself which essentially means to boil. In the mid-19th century, the French scientist Louis Pasteur was tasked by the French government to study what made some wines spoil. His work, which would lead to Pasteur being considered one of the Fathers of Microbiology. The yeast species commonly known as Saccharomyces cerevisiae was first identified in late 19th century enology text as Saccharomyces ellipsoideus due to the shape of the cells. Throughout the 20th century, more than 700 different strains of Saccharomyces cerevisiae were identified, some of these difference include the vigor or speed of fermentation, temperature tolerance, the production of volatile sulfur compounds and other compounds that may influence the aroma of the wine. The primary role of yeast is to convert the present in the grape must into alcohol. It is through this process of fermentation that ethanol is released by the yeast cells as a waste product and this includes glycerol which is produced when an intermediate of the glycolysis cycle is reduced to recharge the NADH enzyme needed to continue other metabolic activities. This is usually produced early in the process before the mechanisms to reduce acetaldehyde into ethanol to recharge NADH becomes the cells primary means of maintaining redox balance. This includes selecting yeast strains that favor glycerol production, increased oxygen exposure, other by-products of yeast include, Methanol – Caused by the demethylation of pectins in the must by enzymes of the yeast. More commonly found in red wines than white but only in small amounts between 20–200 mg/L. Fusel oils – Formed by the decomposition of amino acids by the yeast, succinic acid – Like glycerol, this is often formed early in fermentation. Usually found in concentrations of 500–1200 mg/L, it is an acid in the overall acidity of wine
16.
Saccharomyces cerevisiae
–
Saccharomyces cerevisiae is a species of yeast. It has been instrumental to winemaking, baking, and brewing since ancient times and it is believed to have been originally isolated from the skin of grapes. It is one of the most intensively studied model organisms in molecular and cell biology. It is the microorganism behind the most common type of fermentation, S. cerevisiae cells are round to ovoid, 5–10 μm in diameter. It reproduces by a process known as budding. Many proteins important in biology were first discovered by studying their homologs in yeast, these proteins include cell cycle proteins, signaling proteins. S. cerevisiae is currently the only yeast cell known to have Berkeley bodies present, antibodies against S. cerevisiae are found in 60–70% of patients with Crohns disease and 10–15% of patients with ulcerative colitis. Saccharomyces derives from Latinized Greek and means sugar-mold or sugar-fungus, saccharo being the combining form sugar, cerevisiae comes from Latin and means of beer. Refinements in microbiology following the work of Louis Pasteur led to more advanced methods of culturing pure strains, in 1879, Great Britain introduced specialized growing vats for the production of S. The company created yeast that would rise twice as fast, cutting down on baking time, lesaffre would later create instant yeast in the 1970s, which has gained considerable use and market share at the expense of both fresh and dry yeast in their various applications. In nature, yeast cells are primarily on ripe fruits such as grapes. Since S. cerevisiae is not airborne, it requires a vector to move, queens of social wasps overwintering as adults can harbor yeast cells from autumn to spring and transmit them to their progeny. The intestine of Polistes dominula, a wasp, hosts S. cerevisiae strains as well as S. cerevisiae × S. paradoxus hybrids. The optimum temperature for growth of S. cerevisiae is 30–35 °C, two forms of yeast cells can survive and grow, haploid and diploid. The haploid cells undergo a simple lifecycle of mitosis and growth and this is the asexual form of the fungus. The diploid cells undergo a simple lifecycle of mitosis and growth. The rate at which the cell cycle progresses often differs substantially between haploid and diploid cells. Under conditions of stress, diploid cells can undergo sporulation, entering meiosis and producing four haploid spores and this is the sexual form of the fungus
17.
Density
–
The density, or more precisely, the volumetric mass density, of a substance is its mass per unit volume. The symbol most often used for density is ρ, although the Latin letter D can also be used. Mathematically, density is defined as mass divided by volume, ρ = m V, where ρ is the density, m is the mass, and V is the volume. In some cases, density is defined as its weight per unit volume. For a pure substance the density has the numerical value as its mass concentration. Different materials usually have different densities, and density may be relevant to buoyancy, purity, osmium and iridium are the densest known elements at standard conditions for temperature and pressure but certain chemical compounds may be denser. Thus a relative density less than one means that the floats in water. The density of a material varies with temperature and pressure and this variation is typically small for solids and liquids but much greater for gases. Increasing the pressure on an object decreases the volume of the object, increasing the temperature of a substance decreases its density by increasing its volume. In most materials, heating the bottom of a results in convection of the heat from the bottom to the top. This causes it to rise relative to more dense unheated material, the reciprocal of the density of a substance is occasionally called its specific volume, a term sometimes used in thermodynamics. Density is a property in that increasing the amount of a substance does not increase its density. Archimedes knew that the irregularly shaped wreath could be crushed into a cube whose volume could be calculated easily and compared with the mass, upon this discovery, he leapt from his bath and ran naked through the streets shouting, Eureka. As a result, the term eureka entered common parlance and is used today to indicate a moment of enlightenment, the story first appeared in written form in Vitruvius books of architecture, two centuries after it supposedly took place. Some scholars have doubted the accuracy of this tale, saying among other things that the method would have required precise measurements that would have been difficult to make at the time, from the equation for density, mass density has units of mass divided by volume. As there are units of mass and volume covering many different magnitudes there are a large number of units for mass density in use. The SI unit of kilogram per metre and the cgs unit of gram per cubic centimetre are probably the most commonly used units for density.1,000 kg/m3 equals 1 g/cm3. In industry, other larger or smaller units of mass and or volume are often more practical, see below for a list of some of the most common units of density
18.
Pressing (wine)
–
Pressing in winemaking is the process where juice is extracted from grapes. This can be done with the aid of a press, by hand, or even by the weight of the own grape berries. In white wine production, pressing usually takes place immediately after crushing or/and before primary fermentation, approximately 60-70% of the available juice within the grape berry, the free-run juice, can be released by the crushing process and doesnt require the use of the press. In practice the volume of many wines are made from 85-90% of free-run juice, the timing of pressing and the methods used will influence other decisions in the winemaking process. In white wine making, pressing usually happens immediately after harvest, here, the biggest decision will be how much pressure to apply and how much pressed juice the winemakers wants in addition to the free-run juice. Some grape varieties, such as Sémillon and Aurore have very liquidy pulps that releases juice easily without needing much pressure that could risk tearing the skins, other varieties, such as Catawba, have much tougher pulps that will require more pressing. In red wine production the timing of when to press is one of the most important decisions in the making process since that will be the moment that maceration. Some winemakers use the sugar level scale and press once the wine has reached complete dryness. Often winemakers will use taste to determine if the wine has extracted enough tannins to produce a balanced wine, in these years winemakers might press early, a process that the Australians call short vatting. Grape pulp contains a lot of pectins that create colloid coagulation with these solids that will make the difficult to stabilize. Some winemakers will use pectolytic enzymes during the process to help break down the cell walls to allow the release of more juice freely. These enzymes are used with white wines to assist in clarification. The type of pressing used and the amount of suspended solids plays a role in filtering decisions as a high amount of suspended solids can clog. The earliest wine press was likely the human foot or hand, the pressure applied by these manual means was limited and these early wines were likely pale in color and body. Eventually humans discovered that more juice could be extracted and potentially a better wine could be produced if they developed ways of pressing and it begin with the ancient Egyptians who developed a sack press made of cloth that was squeezed with the aid of a giant tourniquet. The ancient Greeks and Romans developed large wooden wine presses that utilized large beams, capstans and that style of wine press would eventually evolve into the basket press used in the Middle Ages by wine estates of the nobility and Catholic Church. There are many records that showed feudal land tenants were willing to pay a portion of their crop to use a landlords wine press if it was available. This was likely because added volume of wine that pressing could produce versus manual treading was substantial enough to justify the cost, winemaking text began recommending the use of mechanical pressings over feet treading in lagars
19.
Wine press
–
A wine press is a device used to extract juice from crushed grapes during wine making. There are a number of different styles of presses that are used by wine makers, each style of press exerts controlled pressure in order to free the juice from the fruit. The pressure must be controlled, especially grapes, in order to avoid crushing the seeds. Wine was being made at least as long ago as 6000 BC, in 2011, a basket press consists of a large basket filled with the crushed grapes. Pressure is applied through a plate that is forced down onto the fruit, the mechanism to lower the plate is often either a screw or a hydraulic device. The juice flows through openings in the basket, the basket style press was the first type of mechanized press to be developed, and its basic design has not changed in nearly 1000 years. A horizontal screw press works using the principle as the basket press. Instead of a plate being brought down to put pressure on the grapes, plates from either side of a cylinder are brought together to squeeze the grapes. Generally the volume of grapes handled is significantly greater than that of a basket press, a bladder press consists of a large cylinder, closed at each end, into which the fruit is loaded. To press the grapes, a large bladder expands and pushes the grapes against the sides, the juice then flows out through small openings in the cylinder. The cylinder rotates during the process to help homogenize the pressure that is placed on the grapes, a continuous screw press differs from the above presses in that it does not process a single batch of grapes at a time. Instead it uses an Archimedes screw to continuously force grapes up against the wall of the device, juice is extracted, and the pomace continues through to the end where it is extracted. This style of press is used to produce table wines. Flash release is a used in wine pressing. The technique allows for an extraction of phenolic compounds
20.
History of the wine press
–
The earliest wine press was probably the human foot or hand, crushing and squeezing grapes into a bag or container where the contents would ferment. By at least the 18th dynasty, the ancient Egyptians were employing a sack made of cloth that was squeezed with the aid of a giant tourniquet. The wines produced by these presses were usually darker, with more color extracted from the skins, in the 17th century, French traveller Sir Jean Chardin would describe a similar practice still in use thousands of years later in Georgia. The earliest evidence of deliberate winemaking is from excavation at sites like Areni-1 winery in what is now the Vayots Dzor Province of Armenia. This site, dating back to around 4000 BC included a trough that measured about 3 by 3 1/2 feet, a modified version of this sack press had the sack hung between two large poles with workers holding each pole. After the grapes were loaded into the sack, the workers would walk in opposite directions, squeezing the grapes in the bag and capturing the juice in a vat underneath the bag. This early wine press not only had the benefit of exerting pressure on the skins and extracting more juice than treading. One of the earliest known Greek wine presses was discovered in Palekastro in Crete, like most of the earlier presses, it was mainly a stone basin for treading the grapes by feet with a run off drain for the juice to flow. However, there is evidence that some of the later Cretan winemakers would use a pressing method similar to how olive oil was extracted from olives. This press would entail laying the grapes out underneath several planks of wood, the wine made from these rudimentary pressing wasnt held in high esteem by the Greeks, often tainted with impurities and having a short shelf life. Much more prized was the produced from free run juice that was released by the grapes under their own weight before any treading or pressing. This wine was believed to be the most pure and was used for medicinal purposes. In the 2nd century BC, Cato the Elder wrote a vivid and detailed account of the workings of early Roman wine presses, the press would consist of a large horizontal beam held up by two upright fixtures in the front and on upright fixture in the front. The grapes were placed under the beam with pressure was applied by a windlass that was affixed by rope to the front of the beam, rope would also be used wound around the cake of the pressed grape skins to help keep it in place. Marcus Terentius Varro, Columella and Virgil would also include descriptions of the workings of wine presses in their agricultural treatises, yet despite their frequent mentions in ancient writings and archaeological evidence showing the presence of wine presses throughout the Roman empire, their use was actually relatively rare. This was because having a press was a very expensive and large piece of equipment that most Roman farmers, outside the estate holding patricians. Instead, it was more common for Roman estates to have large tanks or trough where grapes were tread upon by feet or paddles. Varro also described in his work De re rustica a type of pressed wine known as lorca that was produced by the left over grape skins being soaked in water that was served to slaves and farm workers
21.
Sparkling wine production
–
Sparkling wine is a wine that becomes carbonated, either through fermentation or by addition of carbon dioxide. The oldest known production of sparkling wine took place in 1531 with the ancestral method, Champagne is the most well-known variant, but there are other variations such as Spanish Cava, Italian Spumante, Crémant from France and Sekt from Germany. Overall, more or less dry wines are most common among the sparkling wines. In popular parlance and also in the title of this article the term sparkling is used for all wines that produce bubbles at the surface after opening, under EU law the term sparkling has a special meaning that does not include all wines that produce bubbles. For this reason the terms fizzy and effervescent are sometimes used to include all bubbly wines, the following terms are increasingly used to designate different bottle pressures, Beady is a wine with less than 1 additional bar of pressure. Semi-sparkling is a wine with 1 to 2.5 additional bars of pressure, semi-sparkling wines include wines labelled as Frizzante, Spritzig, Pétillant and Pearl. Sparkling is a wine with above 3 additional bars of pressure and this is the only wine that can be labelled as sparkling under EU law. Sparkling wines include wines labelled as Champagne, Cava, Mousseux, Crémant, Espumoso, Sekt, fermentation of sugar into alcohol during winemaking always means that carbon dioxide is released. Carbon dioxide has the property of being soluble in water. Production always starts from a base wine, Champagne production the base wine is usually a blend of wines from different grape varieties and different wineries, where the distribution gives the final wine its special character, called cuvée. In some commonly used methods the base wine undergoes a secondary fermentation, in this way the carbon dioxide content is created which, after opening the bottle, produces the bubbles. The dead yeast cells form a precipitate called lees, that helps with appealing aromas to the sparkling wine. The lees is therefore normally removed before the wine is distributed, the main methods used to make sparkling wines are often given as seven, with some variations. The following table shows the features of each method. The methods are described in the text. It should be noted that each method there may be variations from one producer to another. The so-called classic way to sparkling wine is popularly known as the Champagne method or méthode classique which is the official EU designation. Formerly, the designation was méthode champenoise but this designation is no longer permitted, as the former designation suggests, the method is used for the production of most Champagne, and it is slightly more expensive than the Charmat method
22.
Champagne (wine region)
–
The Champagne wine region is a wine region within the historical province of Champagne in the northeast of France. The area is best known for the production of the white wine that bears the regions name. EU law and the laws of most countries reserve the term Champagne exclusively for wines that come from this region located about 100 miles east of Paris, the towns of Reims and Épernay are the commercial centers of the area. Located at the edges of France, the history of the Champagne wine region has had a significant role in the development of this unique terroir. The areas proximity to Paris promoted the economic success in its wine trade but also put the villages. The principal grapes grown in the region include Chardonnay, Pinot noir, Pinot noir is the most widely planted grape in the Aube region and grows very well in Montagne de Reims. Pinot Meunier is the dominant grape in the Vallée de la Marne region, the Côte des Blancs is dedicated almost exclusively to Chardonnay. The Champagne province is located near the limits of the wine world along the 49th parallel. The high altitude and mean temperature of 10 °C creates a difficult environment for wine grapes to fully ripen. Ripening is aided by the presence of forests which helps to stabilize temperatures, the cool temperatures serve to produce high levels of acidity in the resulting grape which is ideal for sparkling wine. During the growing season, the mean July temperature is 18 °C, the average annual rainfall is 630 mm, with 45 mm falling during the harvest month of September. Throughout the year, growers must be mindful of the hazards of fungal disease, ancient oceans left behind chalk subsoil deposits when they receded 70 million years ago. Earthquakes that rocked the region over 10 million years ago pushed the marine sediments of belemnite fossils up to the surface to create the belemnite chalk terrain. The belemnite in the soil allows it to heat from the sun. This soil contributes to the lightness and finesse that is characteristic of Champagne wine, the Aube area is an exception with predominately clay based soil. The chalk is used in the construction of underground cellars that can keep the wines cool through the bottle maturation process. The tradition of crowning kings at Reims contributed to the reputation of the wines that came from this area, the Counts of Champagne ruled the area as an independent county from 950 to 1316. In 1314, the last Count of Champagne assumed the throne as King Louis X of France, the location of Champagne played a large role in its historical prominence as it served as a crossroads for both military and trade routes
23.
Maceration (wine)
–
Maceration is the winemaking process where the phenolic materials of the grape—tannins, coloring agents and flavor compounds—are leached from the grape skins, seeds and stems into the must. To macerate is to soften by soaking, and maceration is the process by which the red wine receives its red color, since 99% of all grape juice is clear-grayish in color. In the production of wines, maceration is either actively avoided or allowed in very limited manner in the form of a short amount of skin contact with the juice prior to pressing. This is more common in the production of varietals with less natural flavor and body structure like Sauvignon blanc, for Rosé, red wines grapes are allowed some maceration between the skins and must, but not to the extent of red wine production. The process of maceration begins, to varying extent, as soon as the skins are broken. Temperature is the force, with higher temperatures encouraging more breakdown and extraction of phenols from the skins. Maceration continues during the period, and can last well past the point when the yeast has converted all sugars into alcohol. The process itself is a one with compounds such as the anthocyanins needing to pass through the cell membrane of the skins to come into contact with the wine. This process seems to slow once the wine reaches a level of 10%. Throughout the fermentation process, carbon dioxide is released as a byproduct of the conversion of sugar into alcohol, the carbon dioxide seeks to escape from the must by rising to the top of the mixture, pushing the grape skins and other materials to the top as well. This forms what is known as a cap that is visible on top of the fermentation vessel and this process of pumping over or punching down the cap is done often throughout the fermentation process, depending on the extent of maceration the winemaker desires. An efficient and modern method of maceration is the process in which compressed air or gas is sequentially injected into the juice. Depending on the varietal, the process of maceration can help bring out many flavors in the wine that would otherwise be lacking and it can enhance the body and mouthfeel for many wines, as well as strengthen the color. Greater extraction can add to the complexity and life expectancy of the wine by developing more complex tannins that will soften over a period of time. With these benefits does come the risk of developing various wine faults, too much extraction can also increase the harshness of some tannins to where the wine is not very approachable to most wine drinkers. One classical method of maceration is grape stomping or pigeage, where grapes are crushed in vats by barefoot workers. This technique was popular in the production of Burgundy wines in the 1970s & 1980s but there is some debate among oenologists about the overall benefits to. Carbonic maceration is the fermentation of whole clusters of grapes in an atmosphere saturated with carbon dioxide
24.
PH
–
In chemistry, pH is a numeric scale used to specify the acidity or basicity of an aqueous solution. It is approximately the negative of the base 10 logarithm of the concentration, measured in units of moles per liter. More precisely it is the negative of the logarithm to base 10 of the activity of the hydrogen ion, solutions with a pH less than 7 are acidic and solutions with a pH greater than 7 are basic. Pure water is neutral, at pH7, being neither an acid nor a base, contrary to popular belief, the pH value can be less than 0 or greater than 14 for very strong acids and bases respectively. The pH scale is traceable to a set of standard solutions whose pH is established by international agreement, the pH of aqueous solutions can be measured with a glass electrode and a pH meter, or an indicator. In the first papers, the notation had the H as a subscript to the p, as so. The exact meaning of the p in pH is disputed, but according to the Carlsberg Foundation and it has also been suggested that the p stands for the German Potenz, others refer to French puissance. Another suggestion is that the p stands for the Latin terms pondus hydrogenii, potentia hydrogenii and it is also suggested that Sørensen used the letters p and q simply to label the test solution and the reference solution. Currently in chemistry, the p stands for decimal cologarithm of, PH is defined as the decimal logarithm of the reciprocal of the hydrogen ion activity, aH+, in a solution. P H = − log 10 = log 10 For example and this definition was adopted because ion-selective electrodes, which are used to measure pH, respond to activity. For H+ number of electrons transferred is one and it follows that electrode potential is proportional to pH when pH is defined in terms of activity. The reference electrode may be a silver chloride electrode or a calomel electrode, the hydrogen-ion selective electrode is a standard hydrogen electrode. Reference electrode | concentrated solution of KCl || test solution | H2 | Pt Firstly, the cell is filled with a solution of hydrogen ion activity. Then the emf, EX, of the cell containing the solution of unknown pH is measured. PH = pH + E S − E X z The difference between the two measured emf values is proportional to pH and this method of calibration avoids the need to know the standard electrode potential. The proportionality constant, 1/z is ideally equal to 12.303 R T / F the Nernstian slope, to apply this process in practice, a glass electrode is used rather than the cumbersome hydrogen electrode. A combined glass electrode has a reference electrode. It is calibrated against buffer solutions of hydrogen ion activity
25.
Acids in wine
–
The acids in wine are an important component in both winemaking and the finished product of wine.9 and 3.9. Generally, the lower the pH, the higher the acidity in the wine, however, there is no direct connection between total acidity and pH. Three primary acids are found in grapes, tartaric, malic and citric acids. During the course of winemaking and in the wines, acetic, butyric, lactic and succinic acids can play significant roles. Sometimes, additional acids, such as ascorbic, sorbic and sulfurous acids, are used in winemaking, in most plants, this organic acid is rare, but it is found in significant concentrations in grape vines. Along with malic acid, and to a lesser extent citric acid, the concentration varies depending on grape variety and the soil content of the vineyard. Some varieties, such as Palomino, are disposed to having high levels of tartaric acids, while Malbec. During flowering, high levels of acid are concentrated in the grape flowers. Less than half of the tartaric acid found in grapes is free standing, during fermentation, these tartrates bind with the lees, pulp debris and precipitated tannins and pigments. While some variance among grape varieties and wine regions exists, generally half of the deposits are soluble in the alcoholic mixture of wine. The crystallization of these tartrates can happen at unpredictable times, and in a bottle may appear like broken glass. Winemakers will often put the wine through cold stabilization, where it is exposed to temperatures below freezing to encourage the tartrates to crystallize, malic acid, along with tartaric acid, is one of the principal organic acids found in wine grapes. It is found in nearly every fruit and berry plant, but is most often associated with green apples and its name comes from the Latin malum meaning “apple”. In the grape vine, malic acid is involved in processes which are essential for the health. Its chemical structure allows it to participate in reactions that transport energy throughout the vine. Its concentration varies depending on the variety, with some varieties, such as Barbera, Carignan and Sylvaner. The levels of acid in grape berries are at their peak just before veraison. As the vine progresses through the stage, malic acid is metabolized in the process of respiration
26.
Wine fault
–
A wine fault or defect is an unpleasant characteristic of a wine often resulting from poor winemaking practices or storage conditions, and leading to wine spoilage. Many of the compounds that cause wine faults are already present in wine. In fact, depending on perception, these concentrations may impart positive characters to the wine, however, when the concentration of these compounds greatly exceeds the sensory threshold, they replace or obscure the flavors and aromas that the wine should be expressing. Ultimately the quality of the wine is reduced, making it less appealing, outside of the winery, other factors within the control of the retailer or end user of the wine can contribute to the perception of flaws in the wine. In wine tasting, there is a big distinction made between what is considered a flaw and a fault, Wine flaws are minor attributes that depart from what are perceived as normal wine characteristics. These include excessive sulfur dioxide, volatile acidity, Brettanomyces or Brett aromas, the amount to which these aromas or attributes become excessive is dependent on the particular tastes and recognition threshold of the wine taster. Generally, a wine exhibiting these qualities is still considered drinkable by most people, however, some flaws such as volatile acidity and Brettanomyces can be considered a fault when they are in such an excess that they overwhelm other components of the wine. Wine faults are generally major attributes that make a wine undrinkable to most wine tasters, examples of wine faults include acetaldehyde, ethyl acetate and cork taint. The vast majority of wine faults are detected by the nose, however, the presence of some wine faults can be detected by visual and taste perceptions. For example, premature oxidation can be noticed by the yellowing and browning of the wines color, the sign of gas bubbles in wines that are not meant to be sparkling can be a sign of refermentation or malolactic fermentation happening in the bottle. Unusual breaks in the color of the wine could be a sign of excessive copper, a wine with an unusual color for its variety or wine region could be a sign of excessive or insufficient maceration or as well as poor temperature controls during fermentation. Tactile clues of potential wine faults include the burning, acidic taste associated with volatile acidity that can make a wine seem out of balance. The oxidation of wine is perhaps the most common of wine faults, as the presence of oxygen, oxidation can occur throughout the winemaking process, and even after the wine has been bottled. Anthocyanins, catechins, epicatechins and other present in wine are those most easily oxidised. Apart from phenolic oxidation, the ethanol present within wine can also be oxidised into other compounds responsible for flavour, acetaldehyde is an intermediate product of yeast fermentation, however, it is more commonly associated with ethanol oxidation catalysed by the enzyme ethanol dehydrogenase. Acetaldehyde production is associated with the presence of surface film forming yeasts and bacteria, such as acetic acid bacteria. The sensory threshold for acetaldehyde is 100-125 mg/L, beyond this level it imparts a sherry type character to the wine which can also be described as green apple, sour and metallic. Acetaldehyde intoxication is also implicated in hangovers, acetic acid in wine, often referred to as volatile acidity or vinegar taint, can be contributed by many wine spoilage yeasts and bacteria
27.
Malic acid
–
Malic acid is an organic compound with the molecular formula C4H6O5. It is an acid that is made by all living organisms, contributes to the pleasantly sour taste of fruits. Malic acid has two forms, though only the L-isomer exists naturally. The salts and esters of malic acid are known as malates, the malate anion is an intermediate in the citric acid cycle. L-Malic acid is the naturally occurring form, whereas a mixture of L-, malate plays an important role in biochemistry. In the C4 carbon fixation process, malate is a source of CO2 in the Calvin cycle, in the citric acid cycle, -malate is an intermediate, formed by the addition of an -OH group on the si face of fumarate. It can also be formed from pyruvate via anaplerotic reactions, malate is also synthesized by the carboxylation of phosphoenolpyruvate in the guard cells of plant leaves. Malate, as an anion, often accompanies potassium cations during the uptake of solutes into the guard cells in order to maintain electrical balance in the cell. The accumulation of these solutes within the cell decreases the solute potential, allowing water to enter the cell. Malic acid was first isolated from apple juice by Carl Wilhelm Scheele in 1785, antoine Lavoisier in 1787 proposed the name acide malique, which is derived from the Latin word for apple, mālum—as is its genus name Malus. In German it is named Äpfelsäure after plural or singular of the fruit apple, Malic acid contributes to the sourness of green apples. It is present in grapes and in most wines with concentrations sometimes as high as 5 g/l and it confers a tart taste to wine, although the amount decreases with increasing fruit ripeness. The taste of malic acid is very clear and pure in rhubarb and it is also a component of some artificial vinegar flavors, such as salt and vinegar flavored potato chips. The process of malolactic fermentation converts malic acid to much milder lactic acid, Malic acid occurs naturally in all fruits and many vegetables, and is generated in fruit metabolism. Malic acid, when added to products, is denoted by E number E296. Malic acid is the source of extreme tartness in United States-produced confectionery and it is also used with or in place of the less sour citric acid in sour sweets. These sweets are sometimes labeled with a warning stating that excessive consumption can cause irritation of the mouth and it is approved for use as a food additive in the EU, US and Australia and New Zealand. Malic acid provides 10 kJ of energy per gram during digestion, racemic malic acid is produced industrially by the double hydration of maleic anhydride
28.
Lees (fermentation)
–
Lees refers to deposits of dead yeast or residual yeast and other particles that precipitate, or are carried by the action of fining, to the bottom of a vat of wine after fermentation and aging. The yeast deposits in beer brewing are known as trub, however, yeast deposits from secondary fermentation of both wine and beer are referred to as lees. This material is the source for most commercial tartaric acid, which is used in cooking, normally the wine is transferred to another container, leaving this sediment behind. Some wines are aged for a time on the lees, leading to a distinctive yeasty aroma. The lees may be stirred in order to promote uptake of the lees flavour, the lees are an important component in the making of Ripasso where the leftover lees from Amarone are used to impart more flavour and colour to partially aged Valpolicella. Sur lie literally translates from French as on lees, sur lie wines are bottled directly from the lees without racking. In the case of great Chardonnay, such as Montrachet, this adds a toasty, nutty hazelnut quality and additional depth, chemically this can alter the oak flavour molecules increasing the integration, and making the oak seem less obtrusive to the palate. This is desirable because oak tannins are an acid. This process can give an added freshness and creaminess to the wine. Muscadet is made in this fashion, the effect of the lees during bottle fermentation for at least 18 months on Champagne is considerable. The bready toasty notes associated with some of the greatest sparkling wines made are the result of sur lie aging, beer on lees is also sometimes made. Many of the beers offered by the Quebec, Canada based Unibroue are on lees, a process in which yeast is added to wine that has completed primary fermentation. This secondary yeast addition typically remains in the wine from two to eight weeks, depending on the wine makers goals, the yeast is stirred frequently during the protocol, and racked off when the protocol is complete. Also known as autolysis, a light lees protocol releases additional mannoproteins and polysaccharides that can influence the flavour
29.
Aging of wine
–
The aging of wine or ageing of wine is potentially able to improve the quality of wine. This distinguishes wine from most other consumable goods, the ability of a wine to age is influenced by many factors including grape variety, vintage, viticultural practices, wine region and winemaking style. The condition that the wine is kept in after bottling can also influence how well a wine ages and may require significant time and financial investment. There is a significant mystique around the aging of wine, as its chemistry was not understood for a long time, the Ancient Greeks and Romans were aware of the potential of aged wines. In Greece, early examples of dried straw wines were noted for their ability to age due to their high sugar contents and these wines were stored in sealed earthenware amphorae and kept for many years. In Rome, the most sought after wines—Falernian and Surrentine—were prized for their ability to age for decades, in the Book of Luke, it is noted that old wine was valued over new wine. Following the Fall of the Roman Empire, appreciation for aged wine was virtually non-existent, most of the wines produced in northern Europe were light bodied, pale in color and with low alcohol. These wines did not have much aging potential and barely lasted a few months before they rapidly deteriorated into vinegar, the older a wine got the cheaper its price became as merchants eagerly sought to rid themselves of aging wine. By the 16th century, sweeter and more alcoholic wines were being made in the Mediterranean, similarly, Riesling from Germany with its combination of acidity and sugar were also demonstrating their ability to age. In the 17th century, two innovations occurred that changed the wine industrys view on aging. One was the development of the cork and bottle which allowed producers to package, the second was the growing popularity of fortifying wines such as Port, Madeira and Sherries. The added alcohol was found to act as a preservative, allowing wines to survive long sea voyages to England, The Americas, the English, in particular, were growing in their appreciation of aged wines like Port and Claret from Bordeaux. Demand for matured wines had an effect on the wine trade. In regions like Bordeaux, Oporto and Burgundy, this dramatically increased the balance of power towards the merchant classes. There is a misconception that wine always improves with age, or that wine improves with extended aging. Some authorities state that more wine is consumed too old than too young, aging changes wine, but does not categorically improve it or worsen it. Fruitness deteriorates rapidly, decreasing markedly after only 6 months in the bottle, due to the cost of storage, it is not economical to age cheap wines, but many varieties of wine do not benefit from aging, regardless of the quality. Experts vary on precise numbers, but typically state that only 5–10% of wine improves after 1 year, in general, wines with a low pH have a greater capability of aging
30.
Beaujolais nouveau
–
Beaujolais nouveau is a red wine made from Gamay grapes produced in the Beaujolais region of France. It is the most popular vin de primeur, fermented for just a few weeks before being released for sale on the third Thursday of November and this Beaujolais Nouveau Day used to see heavy marketing, with races to get the first bottles to different markets around the globe. The current release practice is to ship the wine ahead of the third Thursday of November, Beaujolais had always made a vin de lannée to celebrate the end of the harvest, but until World War II it was only for local consumption. In fact, once the Beaujolais AOC was established in 1937, a few members of the UIVB saw the potential for marketing Beaujolais nouveau. Not only was it a way to lots of vin ordinaire at a good profit. Hence the idea was born of a race to Paris carrying the first bottles of the new vintage and this attracted a lot of media coverage, and by the 1970s had become a national event. The races spread to neighbouring countries in Europe in the 1980s, followed by North America, in 1985, the date was changed to the third Thursday in November to take best advantage of marketing in the following weekend. Beaujolais nouveau is made from the Gamay noir à Jus blanc grape, the grapes must come from the Beaujolais AOC, with those of the ten cru appellations excluded. They are grown in stony, schistous soils, both Beaujolais Nouveau and Beaujolais-Villages Nouveau are produced, the latter comes from the ~30 non-cru villages in the region. By law, all grapes in the region must be harvested by hand, the wine is made using carbonic maceration, whole berry anaerobic fermentation which emphasizes fruit flavors without extracting bitter tannins from the grape skins. Grapes are loaded into a sealed container that is filled with carbon dioxide. Grapes that are crushed at the bottom of the container by the weight of the grapes start to ferment. All this carbon dioxide causes fermentation to take place inside the uncrushed grapes, the resulting wine is fresh, fruity, and very low in tannins. This Beaujolais Day is accompanied by publicity events and heavy advertising, the traditional slogan, even in English-speaking countries, was Le Beaujolais nouveau est arrivé. But in 2005 this was changed to Its Beaujolais Nouveau Time, in the United States, it is promoted as a drink for Thanksgiving, which always falls exactly one week after the wine is released. Many producers release the nouveau with colourful or abstract design that changes every year, duboeuf has silk ties made each year with their labels abstract design, and releases them through select wholesalers and distributors. Beaujolais nouveau is a purple-pink wine reflecting its youth, bottled only 6–8 weeks after harvest, the method of production means that there is very little tannin, and the wine can be dominated by such fruity ester flavours as banana, grape, strawberry, fig and pear drop. The wine is recommended to be chilled to 13 °C
31.
Bordeaux
–
Bordeaux is a port city on the Garonne River in the Gironde department in southwestern France. The municipality of Bordeaux proper has a population of 243,626, together with its suburbs and satellite towns, Bordeaux is the centre of the Bordeaux Métropole. With 749,595 inhabitants and 1,178,335 in the area, it is the fifth largest in France, after Paris, Lyon, Marseille and Lille. It is the capital of the Nouvelle-Aquitaine region, as well as the prefecture of the Gironde department and its inhabitants are called Bordelais or Bordelaises. The term Bordelais may also refer to the city and its surrounding region, Bordeaux is the worlds major wine industry capital. It is home to the main wine fair, Vinexpo. Bordeaux wine has been produced in the region since the 8th century, the historic part of the city is on the UNESCO World Heritage List as an outstanding urban and architectural ensemble of the 18th century. After Paris, Bordeaux has the highest number of preserved buildings of any city in France. In historical times, around 300 BC it was the settlement of a Celtic tribe, the Bituriges Vivisci, the name Bourde is still the name of a river south of the city. In 107 BC, the Battle of Burdigala was fought by the Romans who were defending the Allobroges, a Gallic tribe allied to Rome, the Romans were defeated and their commander, the consul Lucius Cassius Longinus, was killed in the action. The city fell under Roman rule around 60 BC, its importance lying in the commerce of tin, later it became capital of Roman Aquitaine, flourishing especially during the Severan dynasty. In 276 it was sacked by the Vandals, further ravage was brought by the same Vandals in 409, the Visigoths in 414 and the Franks in 498, beginning a period of obscurity for the city. In the late 6th century, the city re-emerged as the seat of a county and an archdiocese within the Merovingian kingdom of the Franks, the city started to play a regional role as a major urban center on the fringes of the newly founded Frankish Duchy of Vasconia. Around 585, a certain Gallactorius is cited as count of Bordeaux, the city was plundered by the troops of Abd er Rahman in 732 after storming the fortified city and overwhelming the Aquitanian garrison. After Duke Eudess defeat, the Aquitanian duke could still save part of its troops, the following year, the Frankish commander descended again over Aquitaine, but clashed in battle with the Aquitanians and left to take on hostile Burgundian authorities and magnates. In 745, Aquitaine faced yet another expedition by Charles sons Pepin and Carloman against Hunald, Hunald was defeated, and his son Waifer replaced him, who in turn confirmed Bordeaux as the capital city. During the last stage of the war against Aquitaine, it was one of Waifers last important strongholds to fall to King Pepin the Shorts troops. Next to Bordeaux, Charlemagne built the fortress of Fronsac on a hill across the border with the Basques, in 778, Seguin was appointed count of Bordeaux, probably undermining the power of the Duke Lupo, and possibly leading to the Battle of Roncevaux Pass that very year
32.
Egg white
–
Albumen is the name for the clear liquid contained within an egg. In chickens it is formed from the layers of secretions of the section of the hens oviduct during the passage of the egg. It forms around fertilized or unfertilized egg yolks, the primary natural purpose of egg white is to protect the yolk and provide additional nutrition for the growth of the embryo. Egg white consists primarily of about 90% water into which is dissolved about 10% proteins, unlike the yolk, which is high in lipids, egg white contains almost no fat, and carbohydrate content is less than 1%. Egg whites contain just over 50% of the protein in the egg, Egg white has many uses in food and also many other uses. Egg white makes up around two-thirds of an egg by weight. Water constitutes about 90% of this, with protein, trace minerals, fatty material, vitamins, and glucose contributing the remainder. A raw U. S. large egg contains around 33 grams of egg white with 3.6 grams of protein,0.24 grams of carbohydrate and 55 milligrams of sodium and it contains no cholesterol and the energy content is about 17 Calories. Egg white is a solution and contains around 148 proteins. The table below lists the major proteins in egg whites by percentage, ovalbumin is the most abundant protein in albumen. Classed as phosphoglycoprotein, during storage, it converts into s-ovalbumin, Denaturation temperature is around 84°C, but it can be easily denatured by physical stresses. Conalbumin/ovotransferrin is a glycoprotein which has the capacity to bind the bi-, at its isoelectric pH, it can bind two cations and assume a red or yellow color. These metal complexes are more stable than the native state. Ovomucoid is the major allergen from egg white and is a heat-resistant glycoprotein found to be a trypsin inhibitor, ovomucin is a glycoprotein which may contribute to the gel-like structure of thick albumen. The amount of ovomucin in the thick albumen is four times greater than in the thin albumen, the physical stress of beating egg whites can create a foam. Two types of stress are caused by beating them with a whisk. The second stress comes from the mixing of air into the whites, when beating egg whites, they are classified in three stages according to the peaks they form when the beater is lifted, soft, firm, and stiff peaks. Overbeaten eggs take on a dry appearance, and eventually collapse, Egg whites do not beat up correctly if they are exposed to any form of fat, such as cooking oils or the fats contained in egg yolk
33.
Gelatin
–
Gelatin or gelatine is a translucent, colorless, brittle, flavorless food derived from collagen obtained from various animal body parts. It is commonly used as an agent in food, pharmaceutical drugs, vitamin capsules, photography. Substances containing gelatin or functioning in a way are called gelatinous. It is found in most gummy candy, as well as other such as marshmallows, gelatin desserts, and some ice creams, dips. Gelatin for recipe use comes in the form of sheets, granules, instant types can be added to the food as they are, others need to be soaked in water beforehand. During hydrolysis, the molecular bonds between individual collagen strands are broken down into a form that rearranges more easily. Its chemical composition is, in respects, closely similar to that of its parent collagen. Photographic and pharmaceutical grades of gelatin generally are sourced from beef bones, Gelatin readily dissolves in hot water and sets to a gel on cooling. When added directly to water, it does not dissolve well. Gelatin also is soluble in most polar solvents, Gelatin solutions show viscoelastic flow and streaming birefringence. Solubility is determined by the method of manufacture, typically, gelatin can be dispersed in a relatively concentrated acid. Such dispersions are stable for 10–15 days with little or no changes and are suitable for coating purposes or for extrusion into a precipitating bath. The mechanical properties of gelatin gels are very sensitive to variations, the previous thermal history of the gels. The upper melting point is below human body temperature, a factor that is important for mouthfeel of foods produced with gelatin, the viscosity of the gelatin-water mixture is greatest when the gelatin concentration is high and the mixture is kept cool at about 4 °C. The gel strength is quantified using the Bloom test, the worldwide production amount of gelatin is about 375, 000–400,000 tonnes per year. On a commercial scale, gelatin is made from by-products of the meat, recently, fish by-products also have been considered suitable because they eliminate some of the religious obstacles surrounding gelatin consumption. Gelatin is derived from pork skins, pork, and cattle bones, the raw materials are prepared by different curing, acid, and alkali processes that are employed to extract the dried collagen hydrolysate. These processes may take weeks, and differences in such processes have great effects on the properties of the final gelatin products
34.
Yeast
–
Yeasts are eukaryotic, single-celled microorganisms classified as members of the fungus kingdom. The yeast lineage originated hundreds of millions of years ago, and 1,500 species are currently identified and they are estimated to constitute 1% of all described fungal species. Yeast sizes vary greatly, depending on species and environment, typically measuring 3–4 µm in diameter, most yeasts reproduce asexually by mitosis, and many do so by the asymmetric division process known as budding. Yeasts, with their growth habit, can be contrasted with molds. Fungal species that can take both forms are called dimorphic fungi and it is also a centrally important model organism in modern cell biology research, and is one of the most thoroughly researched eukaryotic microorganisms. Researchers have used it to information about the biology of the eukaryotic cell. Other species of yeasts, such as Candida albicans, are opportunistic pathogens, yeasts have recently been used to generate electricity in microbial fuel cells, and produce ethanol for the biofuel industry. Yeasts do not form a taxonomic or phylogenetic grouping. The budding yeasts are classified in the order Saccharomycetales, within the phylum Ascomycota, the word yeast comes from Old English gist, gyst, and from the Indo-European root yes-, meaning boil, foam, or bubble. Yeast microbes are probably one of the earliest domesticated organisms, archaeologists digging in Egyptian ruins found early grinding stones and baking chambers for yeast-raised bread, as well as drawings of 4, 000-year-old bakeries and breweries. In 1680, Dutch naturalist Anton van Leeuwenhoek first microscopically observed yeast, but at the time did not consider them to be living organisms, researchers were doubtful whether yeasts were algae or fungi, but in 1837 Theodor Schwann recognized them as fungi. In 1857, French microbiologist Louis Pasteur proved in the paper Mémoire sur la fermentation alcoolique that alcoholic fermentation was conducted by living yeasts and not by a chemical catalyst. Pasteur showed that by bubbling oxygen into the yeast broth, cell growth could be increased, by the late 18th century, two yeast strains used in brewing had been identified, Saccharomyces cerevisiae and S. carlsbergensis. S. cerevisiae has been sold commercially by the Dutch for bread-making since 1780, while, around 1800, in 1825, a method was developed to remove the liquid so the yeast could be prepared as solid blocks. The industrial production of yeast blocks was enhanced by the introduction of the press in 1867. In 1872, Baron Max de Springer developed a process to create granulated yeast. Yeasts are chemoorganotrophs, as they use organic compounds as a source of energy, carbon is obtained mostly from hexose sugars, such as glucose and fructose, or disaccharides such as sucrose and maltose. Some species can metabolize pentose sugars such as ribose, alcohols, Yeast species either require oxygen for aerobic cellular respiration or are anaerobic, but also have aerobic methods of energy production
35.
Bacteria
–
Bacteria constitute a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria have a number of shapes, ranging from spheres to rods, Bacteria were among the first life forms to appear on Earth, and are present in most of its habitats. Bacteria inhabit soil, water, acidic hot springs, radioactive waste, Bacteria also live in symbiotic and parasitic relationships with plants and animals. Most bacteria have not been characterised, and only half of the bacterial phyla have species that can be grown in the laboratory. The study of bacteria is known as bacteriology, a branch of microbiology, There are typically 40 million bacterial cells in a gram of soil and a million bacterial cells in a millilitre of fresh water. There are approximately 5×1030 bacteria on Earth, forming a biomass which exceeds that of all plants, Bacteria are vital in many stages of the nutrient cycle by recycling nutrients such as the fixation of nitrogen from the atmosphere. The nutrient cycle includes the decomposition of bodies and bacteria are responsible for the putrefaction stage in this process. In March 2013, data reported by researchers in October 2012, was published and it was suggested that bacteria thrive in the Mariana Trench, which with a depth of up to 11 kilometres is the deepest known part of the oceans. Other researchers reported related studies that microbes thrive inside rocks up to 580 metres below the sea floor under 2.6 kilometres of ocean off the coast of the northwestern United States. According to one of the researchers, You can find microbes everywhere—theyre extremely adaptable to conditions, the vast majority of the bacteria in the body are rendered harmless by the protective effects of the immune system, though many are beneficial particularly in the gut flora. However several species of bacteria are pathogenic and cause diseases, including cholera, syphilis, anthrax, leprosy. The most common fatal diseases are respiratory infections, with tuberculosis alone killing about 2 million people per year. In developed countries, antibiotics are used to treat infections and are also used in farming, making antibiotic resistance a growing problem. Once regarded as constituting the class Schizomycetes, bacteria are now classified as prokaryotes. Unlike cells of animals and other eukaryotes, bacterial cells do not contain a nucleus and these evolutionary domains are called Bacteria and Archaea. The ancestors of modern bacteria were unicellular microorganisms that were the first forms of life to appear on Earth, for about 3 billion years, most organisms were microscopic, and bacteria and archaea were the dominant forms of life. In 2008, fossils of macroorganisms were discovered and named as the Francevillian biota, however, gene sequences can be used to reconstruct the bacterial phylogeny, and these studies indicate that bacteria diverged first from the archaeal/eukaryotic lineage. Bacteria were also involved in the second great evolutionary divergence, that of the archaea, here, eukaryotes resulted from the entering of ancient bacteria into endosymbiotic associations with the ancestors of eukaryotic cells, which were themselves possibly related to the Archaea
36.
Glass bottle
–
A glass bottle is a bottle created from glass. Glass bottles can vary in size considerably, but are most commonly found in sizes ranging between about 10ml and 5 litres, common uses for glass bottles include food condiments, soda, liquor, cosmetics, pickling and preservatives. These types of bottles are utilitarian and serve a purpose in commercial industries, glass bottles and glass jars are in many households around the world. The first glass bottles were produced in south east Asia around 100 BCE, americas glass bottle and glass jar industry was born in the early 1600s when settlers in Jamestown built the first glass melting furnace. The invention of the glass bottle blowing machine in 1880 industrialized the process of making bottles. The earliest bottles or vessels were made by ancient man, ingredients were melted to make glass and then clay forms were dipped into the molten liquid. When the glass cooled off, the clay was chipped out of the inside leaving just the hollow glass vessel and this glass was very thin as the fire was not as hot as modern day furnaces. The blowpipe was invented around 1 B. C, now, molten glass could be gathered on the end of the blow pipe and blown into the other end to create a hollow vessel. Eventually the use of a mold was introduced, followed by the invention of a machine called the Press. In 1904 Michael Owens invented the automatic bottle machine, once made, bottles may suffer from internal stresses as a result of unequal, or too rapid cooling. An annealing oven, or lehr is used to cool glass containers slowly to prevent stress, when a glass bottle filled with liquid is dropped or subjected to shock, the water hammer effect may cause hydrodynamic stress, breaking the bottle. Markings Modern bottles, when moulded, will be given marks on the heel of the bottle, early bottles were sealed with wax, and later stoppered with a cork. More common today are screw caps and stoppers
37.
Bung
–
A bung, stopper or cork is a truncated cylindrical or conical closure to seal a container, such as a bottle, tube or barrel. Unlike a lid, which encloses a container from the outside without displacing the inner volume, a glass stopper is often called a ground glass joint, a rubber stopper is sometimes called a rubber bung, and a cork stopper is called simply a cork. Bung stoppers used for wine bottles are referred to as corks, a common every-day example of a bung is the cork of a wine bottle. Bungs are used to seal the bunghole of barrels, other bungs, particularly those used in chemical barrels, may be made of metal and be screwed into place via threading. Ground glass joint are commonly used with laboratory glassware, mainly because of their nonreactivity, some stoppers used in labs have holes in them to allow the insertion of glass or rubber tubing. This is often used when a reaction is taking place in the flask or test tube, for instance, if one were to boil water in a test tube and wanted to collect the water vapor, one could seal the test tube with a stopper with holes in it. With tubing inserted into the hole, when the tube is heated, water vapor will rise through the hole, make its way through the tubing, and into the collection chamber of choice. The water vapor would not be able to escape into the air, because the stopper, in chemistry, bungs made of hardened rubber are frequently used in high school level demonstrations, or in small-scale experimental set-ups involving non-corrosive gases. Some chemistry bungs may also one or more holes so a glass tube or laboratory funnel may be inserted through the bung. In all cases, the keeps the experimentation environment sealed so that liquids or gases cannot escape. For applications that place higher demand on the bung in terms of temperature and mechanical stability or solvent resistance, silicone bungs are the standard for wine barrels and come in a number of varieties
38.
Tetra Pak
–
Tetra Pak is a multinational food packaging and processing company of Swedish origin with head offices in Lund, Sweden, and Lausanne, Switzerland. Tetra Pak was founded by Ruben Rausing and built on Erik Wallenbergs innovation, in the 1960s and 1970s, the development of the Tetra Brik package and the aseptic packaging technology made possible a cold chain supply, substantially facilitating distribution and storage. Tetra Pak is currently the largest food packaging company in the world by sales, operating in more than 170 countries, Tetra Pak was created in 1951 as a subsidiary to Åkerlund & Rausing, a food carton company established in Malmö in 1929 by Ruben Rausing and Erik Åkerlund. At the time, these were sold over the counter in cumbersome glass bottles or impractical paper wraps in most European countries, at the end of the 1920s, Rausing bought a run-down packaging factory in Malmö together with the industrialist Erik Åkerlund. Åkerlund & Rausing was the first packaging company in Scandinavia and eventually became a manufacturer of dry food cartons. Initially, however, Åkerlund & Rausing had difficulties making profits and in 1933 Åkerlund sold his share to Rausing, who became the sole owner. The new package had to be cheap to be able to compete with loose milk, meaning that a minimum of material waste. In 1943, the Åkerlund & Rausing lab started to work on developing the milk carton, the idea was simple but efficient, making optimal use of the material involved. After some initial hesitation, Rausing understood the potential of the package, the rest of the 1940s were spent developing viable packaging materials and solving the technical problems of filling, sealing, and distribution. AB Tetra Pak was established in Lund, Sweden, in 1951, in the subsequent years, the tetrahedron packages became more and more frequent in Swedish grocery stores, and in 1954, the first machine producing 500 ml milk packages was sold to a Stockholm dairy. That same year the first machine was exported to Hamburg, Germany, soon to be followed by France, Italy, Switzerland and later the Soviet Union and Japan. Rausing relentlessly strove to improve the Tetra Classic system, wrought with many problems during the 1950s. The different projects – the tetrahedron, the packaging technology, Tetra Brik – all demanded extremely large resources. Indeed, Tetra Paks commercial breakthrough did not arrive until the mid-1960s with the new Tetra Brik package, introduced in 1963, to liberate capital, Åkerlund & Rausing was sold in 1965 while AB Tetra Pak was retained. In 1962, the first Tetra Classic Aseptic machine outside of Europe was installed in Lebanon, in 1981, Tetra Pak relocated its corporate headquarters to Lausanne, Switzerland, for tax reasons, however retaining all R&D functions in Lund, Sweden. The deal drew anti-competitive scrutiny from the European Commission, but it went through various concessions from both companies. After the merger with Alfa Laval, Tetra Pak announced plans to return the headquarters to Sweden, Alfa Lavals liquid processing unit was absorbed into Tetra Pak and the unit specialising on machinery for dairy production was organised separately in Alfa Laval Agri. Alfa Laval Agri was later renamed DeLaval, after Alfa Lavals founder Gustaf de Laval, the part of Alfa Laval that was not directly linked to Tetra Paks activities – heat exchangers and separation equipment among others – was sold in 2000 to Swedish finance group Industri Kapital
39.
Plastic bottle
–
A plastic bottle is a bottle constructed from plastic. Plastic bottles are used to store liquids such as water, soft drinks, motor oil, cooking oil, medicine, shampoo, milk. The size ranges from very small sample bottles to large carboys, plastic bottles were first used commercially in 1947 but remained relatively expensive until the early 1960s when high-density polyethylene was introduced. They quickly became popular with manufacturers and customers due to their lightweight nature and relatively low production and transportation costs compared with glass bottles. However, the biggest advantage plastic bottles have over glass is their resistance to breakage. Except for wine and beer, the industry has almost completely replaced glass bottles with plastic bottles. Plastic bottles are formed using a variety of techniques, high Density Polyethylene is the most widely used resin for plastic bottles. This material is economical, impact resistant, and provides a good moisture barrier, HDPE is compatible with a wide range of products including acids and caustics but is not compatible with solvents. It is supplied in FDA-approved food grade, HDPE is naturally translucent and flexible. The addition of color will make HDPE opaque, but not glossy, HDPE lends itself to silk screen decoration. While HDPE provides good protection at below freezing temperatures, it cannot be used with products filled above 160 °F or products requiring a hermetic seal, low Density Polyethylene is similar to HDPE in composition. It is less rigid and generally less chemically resistant than HDPE, LDPE is used primarily for squeeze applications. LDPE is significantly more expensive than HDPE, Polyethylene Terephthalate is commonly used for carbonated beverage, water bottles and many food products. PET provides very good alcohol and essential oil barrier properties, generally good chemical resistance, the orienting process serves to improve gas and moisture barrier properties and impact strength. This material does not provide resistance to high temperature applications—max. 200 °F. Polyvinyl Chloride is naturally clear, has good resistance to oils. It provides an excellent barrier to most gases and its drop impact resistance is very good. This material is resistant, but it is vulnerable to some solvents
40.
Health effects of wine
–
The health effects of wine are mainly determined by its active ingredient alcohol. Some studies found that drinking small quantities of alcohol is associated with a risk of heart disease, stroke, diabetes mellitus, metabolic syndrome. However, other studies found no such effect, drinking more than the standard drink amount increases the risk of heart disease, high blood pressure, atrial fibrillation, stroke and cancer. Mixed results are observed in light drinking and cancer mortality. Risk is greater in younger people due to binge drinking which may result in violence or accidents, about 3.3 million deaths are believed to be due to alcohol each year. Alcoholism reduces a persons life expectancy by around ten years and excessive use is the third leading cause of early death in the United States. According to systematic reviews and medical associations, people who are nondrinkers should not start drinking wine, ancient Egyptian Papyri and Sumerian tablets dating back to 2200 BC detail the medicinal role of wine, making it the worlds oldest documented human-made medicine. Nearly all research into the medical benefits of wine consumption makes a distinction between moderate consumption and heavy or binge drinking. Moderate levels of consumption vary by the according to age, gender, genetics, weight and body stature, as well as situational conditions. In general, woman absorb alcohol more quickly than men due to their body water content. Some experts define moderate consumption as less than one 5-US-fluid-ounce glass of wine per day for women, the view of consuming wine in moderation has a history recorded as early as the Greek poet Eubulus who believed that three bowls were the ideal amount of wine to consume. The number of three bowls for moderation is a theme throughout Greek writing, today the standard 750 ml wine bottle contains roughly the volume of three kylix cups. However, the cups would have contained a diluted wine. Epidemiological studies have found an association between moderate alcohol consumption and increased bone mineral density. Most of this research has been conducted with women. The International Agency for Research on Cancer of the World Health Organization has classified alcohol as a Group 1 carcinogen, studies have shown that heavy drinkers put themselves at greater risk for heart disease and developing potentially fatal cardiac arrhythmias. Excessive alcohol consumption can cause blood pressure, increase cholesterol levels. The main cause of heart attacks and the pain of angina is the lack of oxygen caused by blood clots, professional cardiology associations recommend that people who are currently nondrinkers should not start drinking alcohol
41.
Storage of wine
–
Storage of wine is an important consideration for wine that is being kept for long-term aging. While most wine is consumed within 24 hours of purchase, fine wines are often set aside for long-term storage, Wine is one of the few commodities that can improve with age, but it can also rapidly deteriorate if kept in inadequate conditions. The three factors that have the most direct impact on a wines condition are light, humidity, historically, the storage of wine was handled by wine merchants. Since the mid-20th century, however, consumers have been increasingly storing their own wine in home-based wine cellars, the three factors that have the most pronounced effect on wine in storage are light, humidity, and temperature. Strong, direct sunlight or incandescent light can adversely react with compounds in wine. Delicate, light-bodied white wines run the greatest risk from light exposure, wines packaged in clear, light green and blue colored bottles are the most vulnerable to light, and may need extra precautions for storage. For example, the Champagne house of Louis Roederer uses cellophane wrap to protect its premium cuvee Cristal from light, in the cellar, wines are stored in corrugated boxes or wooden crates to protect the wines from direct light. Some degree of humidity is required in order to keep wines with cork enclosures from drying out, even when wine bottles are stored on their sides, one side of the cork is still exposed to air. Should the cork begin to dry out, it can allow oxygen to enter the bottle, filling the ullage space, excessive humidity can also pose the risk of damaging wine labels, which may hinder identification or hurt potential resale value. Wine experts such as Jancis Robinson note that 75% humidity is often cited as ideal, some wine experts debate the importance of humidity for proper wine storage. However, Alexis Lichine contends that low humidity can still be detrimental to premium wine quality due to the risk of the drying out. As a way of maintaining optimal humidity, Lichine recommends spreading half an inch of gravel on the floor of a wine cellar, Wine is very susceptible to changes in temperature, with temperature control being an important consideration in wine storage. If the wine is exposed to too high a temperature for long periods of time, it may be spoiled or become cooked, dramatic temperature swings can also cause adverse chemical reactions in the wine that may lead to a variety of wine faults. In general, a wine has a potential to develop complexity. The lower the temperature, the more slowly a wine develops, on average, the rate of chemical reactions in wine doubles with each 18 °F increase in temperature. Wine expert Karen MacNeil recommends keeping wine intended for aging in an area with a constant temperature around 55 °F. Wine can be stored at temperatures as high as 69 °F without long-term negative effect, professor Cornelius Ough of the University of California, Davis believes that wine can be exposed to temperatures as high as 120 °F for a few hours and not be damaged. It is not normally possible to freeze wine in the bottle as there is insufficient room for it to expand as it freezes, in a particular study, vibrations of different frequencies have been shown to have their own distinct effect on the chemistry of the wine
42.
International Standard Book Number
–
The International Standard Book Number is a unique numeric commercial book identifier. An ISBN is assigned to each edition and variation of a book, for example, an e-book, a paperback and a hardcover edition of the same book would each have a different ISBN. The ISBN is 13 digits long if assigned on or after 1 January 2007, the method of assigning an ISBN is nation-based and varies from country to country, often depending on how large the publishing industry is within a country. The initial ISBN configuration of recognition was generated in 1967 based upon the 9-digit Standard Book Numbering created in 1966, the 10-digit ISBN format was developed by the International Organization for Standardization and was published in 1970 as international standard ISO2108. Occasionally, a book may appear without a printed ISBN if it is printed privately or the author does not follow the usual ISBN procedure, however, this can be rectified later. Another identifier, the International Standard Serial Number, identifies periodical publications such as magazines, the ISBN configuration of recognition was generated in 1967 in the United Kingdom by David Whitaker and in 1968 in the US by Emery Koltay. The 10-digit ISBN format was developed by the International Organization for Standardization and was published in 1970 as international standard ISO2108, the United Kingdom continued to use the 9-digit SBN code until 1974. The ISO on-line facility only refers back to 1978, an SBN may be converted to an ISBN by prefixing the digit 0. For example, the edition of Mr. J. G. Reeder Returns, published by Hodder in 1965, has SBN340013818 -340 indicating the publisher,01381 their serial number. This can be converted to ISBN 0-340-01381-8, the check digit does not need to be re-calculated, since 1 January 2007, ISBNs have contained 13 digits, a format that is compatible with Bookland European Article Number EAN-13s. An ISBN is assigned to each edition and variation of a book, for example, an ebook, a paperback, and a hardcover edition of the same book would each have a different ISBN. The ISBN is 13 digits long if assigned on or after 1 January 2007, a 13-digit ISBN can be separated into its parts, and when this is done it is customary to separate the parts with hyphens or spaces. Separating the parts of a 10-digit ISBN is also done with either hyphens or spaces, figuring out how to correctly separate a given ISBN number is complicated, because most of the parts do not use a fixed number of digits. ISBN issuance is country-specific, in that ISBNs are issued by the ISBN registration agency that is responsible for country or territory regardless of the publication language. Some ISBN registration agencies are based in national libraries or within ministries of culture, in other cases, the ISBN registration service is provided by organisations such as bibliographic data providers that are not government funded. In Canada, ISBNs are issued at no cost with the purpose of encouraging Canadian culture. In the United Kingdom, United States, and some countries, where the service is provided by non-government-funded organisations. Australia, ISBNs are issued by the library services agency Thorpe-Bowker
43.
Oxford University Press
–
Oxford University Press is the largest university press in the world, and the second oldest after Cambridge University Press. It is a department of the University of Oxford and is governed by a group of 15 academics appointed by the known as the delegates of the press. They are headed by the secretary to the delegates, who serves as OUPs chief executive, Oxford University has used a similar system to oversee OUP since the 17th century. The university became involved in the print trade around 1480, and grew into a printer of Bibles, prayer books. OUP took on the project became the Oxford English Dictionary in the late 19th century. Moves into international markets led to OUP opening its own offices outside the United Kingdom, by contracting out its printing and binding operations, the modern OUP publishes some 6,000 new titles around the world each year. OUP was first exempted from United States corporation tax in 1972, as a department of a charity, OUP is exempt from income tax and corporate tax in most countries, but may pay sales and other commercial taxes on its products. The OUP today transfers 30% of its surplus to the rest of the university. OUP is the largest university press in the world by the number of publications, publishing more than 6,000 new books every year, the Oxford University Press Museum is located on Great Clarendon Street, Oxford. Visits must be booked in advance and are led by a member of the archive staff, displays include a 19th-century printing press, the OUP buildings, and the printing and history of the Oxford Almanack, Alice in Wonderland and the Oxford English Dictionary. The first printer associated with Oxford University was Theoderic Rood, the first book printed in Oxford, in 1478, an edition of Rufinuss Expositio in symbolum apostolorum, was printed by another, anonymous, printer. Famously, this was mis-dated in Roman numerals as 1468, thus apparently pre-dating Caxton, roods printing included John Ankywylls Compendium totius grammaticae, which set new standards for teaching of Latin grammar. After Rood, printing connected with the university remained sporadic for over half a century, the chancellor, Robert Dudley, 1st Earl of Leicester, pleaded Oxfords case. Some royal assent was obtained, since the printer Joseph Barnes began work, Oxfords chancellor, Archbishop William Laud, consolidated the legal status of the universitys printing in the 1630s. Laud envisaged a unified press of world repute, Oxford would establish it on university property, govern its operations, employ its staff, determine its printed work, and benefit from its proceeds. To that end, he petitioned Charles I for rights that would enable Oxford to compete with the Stationers Company and the Kings Printer and these were brought together in Oxfords Great Charter in 1636, which gave the university the right to print all manner of books. Laud also obtained the privilege from the Crown of printing the King James or Authorized Version of Scripture at Oxford and this privilege created substantial returns in the next 250 years, although initially it was held in abeyance. The Stationers Company was deeply alarmed by the threat to its trade, under this, the Stationers paid an annual rent for the university not to exercise its full printing rights – money Oxford used to purchase new printing equipment for smaller purposes
44.
Annual growth cycle of grapevines
–
From a winemaking perspective, each step in the process plays a vital role in the development of grapes with ideal characteristics for making wine. The stages of the growth cycle usually become observable within the first year of a vines life. The amount of time spent at each stage of the cycle depends on a number of factors-most notably the type of climate. The grape starts its growth cycle in the spring with bud break. In the Northern Hemisphere, this stage begins around March while in the Southern Hemisphere it begins around September when daily temperatures begin to surpass 10 °C, if the vine had been pruned during the winter, the start of this cycle is signaled by a bleeding of the vine. During this period a single vine can bleed up to 5 litres of water, tiny buds on the vine start to swell and eventually shoots begin to grow from the buds. Buds are the part of the vine that rest between the vines stem and the petiole. Inside the buds contain usually three primordial shoots and these buds appear in the summer of previous growth cycle green and covered in scales. During winter dormancy they turn brown until the spring when the vine begins the process of bud break, the energy to facilitate this growth comes from reserves of carbohydrate stored in roots and wood of the vine from the last growth cycle. Eventually the shoots sprout tiny leaves that can begin the process of photosynthesis, in warm climates, after about 4 weeks the growth of the shoots starts to rapidly accelerate with the shoots growing in length an average of 3 cm a day. In temperate climates, where temperatures can reach above 10 °C in mid-winter, after bud break, the young shoots are very vulnerable to frost damage with vineyard managers going to great lengths protect the fragile shoots should temperature dramatically drop below freezing. This can include setting up heaters or wind circulators in the vineyard to keep air from settling on the vines. Depending on temperatures, 40–80 days after bud break the process of flowering begins with small flower clusters appearing on the tips of the young shoots looking like buttons. Flowering occurs when average daily temperatures stay between 15–20 °C which in the Northern Hemisphere wine regions is generally around May and for the Southern Hemisphere regions around November, a few weeks after the initial clusters appear, the flowers start to grow in size with individual flowers becoming observable. It is during this stage of flowering that the pollination and fertilization of the takes place with the resulting product being a grape berry. Hermaphroditic vines are preferred for cultivation because each vine is more likely to self-pollinate, at the beginning of the flowering process the only part that is visible is the fused cap of petals known as the calyptra. Shortly after the calyptra is shed, liberating the pollen from the anthers of the stamen, wind and insects generally play only a small role in aiding pollination, with the process being mostly self-contained within the vine. But cross-pollination between vine species is possible as in the cases of the origins of several varieties like Cabernet Sauvignon
45.
Aroma of wine
–
It is through the aromas of wine that wine is smelled. The human tongue is limited to the primary tastes perceived by taste receptors on the tongue-sourness, bitterness, saltiness, sweetness and savoriness. The wide array of fruit, earthy, floral, herbal, mineral, in wine tasting, wine is sometimes smelled before being drunk in order to identify some components of the wine that may be present. Different terms are used to describe what is being smelled, the most basic term is aroma which generally refers to a pleasant smell as opposed to odor which refers to an unpleasant smell or possible wine fault. The term aroma may be distinguished from bouquet which generally refers to the smells that arise from the chemical reactions of fermentation. In professional wine tasting, there is generally a distinction made between aromas and a wines bouquet while in casual wine tasting these two terms are used interchangeably. An aroma refers to the unique to the grape variety and are most readily demonstrated in a varietal wine—such as lychees with Gewürztraminer or black currant with Cabernet Sauvignon. These are smells that are associated with a young wine. As a wine ages, chemical reactions among acids, sugars, alcohols and these can include honey in an aged Sauternes or truffles in a Pinot noir. The term bouquet can also be expanded to include the smells derived from fermentation, in Burgundy, the aromas of wines are sub-divided into three categories-primary, secondary and tertiary aromas. Primary aromas are those specific to the grape variety itself, secondary aromas are those derived from fermentation. Tertiary aromas are those that develop through either bottle or oak aging, the technique of microoxygenation affects the aromatic bouquet. Within wine there are volatile and non-volatile compounds that contribute to the make up of a wines aroma, as a wine ages and matures, changes and developments in aroma will continue to take place but at a slower and more gradual pace. Volatile aroma compounds are present in the skin and juice of a grape berry, the diverse spectrum of aromas associated with individual grape varieties is a reflection of the vines adaptation to ecological conditions and competition among other plants. The majority of volatile compounds responsible for aroma combine with sugars in the wine to form odorless glycosides, through the process of hydrolysis, caused by enzymes or acids in the wine, they revert into an aromatic form. The act of tasting wine is essentially the act of smelling these vaporized aroma compounds, olfactory receptors cells, each sensitive to a different aroma, pick up these compounds and transfer the information to the brain by way of the olfactory bulb. In the 1980s there was renewed focus in studying the correlation between aroma/flavor compounds in grapes and the quality of wine. Scientists were able to use chromatograph-mass spectrometers to identify volatile aroma compounds in various grape varieties, study of the compounds responsible for aroma and flavor, as well as their correlation with a wines quality, is ongoing
