1.
Sugar
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Sugar is the generic name for sweet, soluble carbohydrates, many of which are used in food. There are various types of derived from different sources. Simple sugars are called monosaccharides and include glucose, fructose, the table sugar or granulated sugar most customarily used as food is sucrose, a disaccharide of glucose and fructose. Sugar is used in prepared foods and it is added to some foods, in the body, sucrose is hydrolysed into the simple sugars fructose and glucose. Other disaccharides include maltose from malted grain, and lactose from milk, longer chains of sugars are called oligosaccharides or polysaccharides. Some other chemical substances, such as glycerol may also have a sweet taste, low-calorie food substitutes for sugar, described as artificial sweeteners, include aspartame and sucralose, a chlorinated derivative of sucrose. Sugars are found in the tissues of most plants and are present in sufficient concentrations for efficient commercial extraction in sugarcane, the world production of sugar in 2011 was about 168 million tonnes. The average person consumes about 24 kilograms of sugar each year, equivalent to over 260 food calories per person, since the latter part of the twentieth century, it has been questioned whether a diet high in sugars, especially refined sugars, is good for human health. Sugar has been linked to obesity, and suspected of, or fully implicated as a cause in the occurrence of diabetes, cardiovascular disease, dementia, macular degeneration, the etymology reflects the spread of the commodity. The English word sugar ultimately originates from the Sanskrit शर्करा, via Arabic سكر as granular or candied sugar, the contemporary Italian word is zucchero, whereas the Spanish and Portuguese words, azúcar and açúcar, respectively, have kept a trace of the Arabic definite article. The Old French word is zuchre and the contemporary French, sucre, the earliest Greek word attested is σάκχαρις. The English word jaggery, a brown sugar made from date palm sap or sugarcane juice, has a similar etymological origin – Portuguese jagara from the Sanskrit शर्करा. Sugar has been produced in the Indian subcontinent since ancient times and it was not plentiful or cheap in early times and honey was more often used for sweetening in most parts of the world. Originally, people chewed raw sugarcane to extract its sweetness, sugarcane was a native of tropical South Asia and Southeast Asia. Different species seem to have originated from different locations with Saccharum barberi originating in India and S. edule, one of the earliest historical references to sugarcane is in Chinese manuscripts dating back to 8th century BC that state that the use of sugarcane originated in India. Sugar was found in Europe by the 1st century AD, but only as an imported medicine and it is a kind of honey found in cane, white as gum, and it crunches between the teeth. It comes in lumps the size of a hazelnut, sugar is used only for medical purposes. Sugar remained relatively unimportant until the Indians discovered methods of turning sugarcane juice into granulated crystals that were easier to store, crystallized sugar was discovered by the time of the Imperial Guptas, around the 5th century AD
2.
Carbon
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Carbon is a chemical element with symbol C and atomic number 6. It is nonmetallic and tetravalent—making four electrons available to form covalent chemical bonds, three isotopes occur naturally, 12C and 13C being stable, while 14C is a radioactive isotope, decaying with a half-life of about 5,730 years. Carbon is one of the few elements known since antiquity, Carbon is the 15th most abundant element in the Earths crust, and the fourth most abundant element in the universe by mass after hydrogen, helium, and oxygen. It is the second most abundant element in the body by mass after oxygen. The atoms of carbon can bond together in different ways, termed allotropes of carbon, the best known are graphite, diamond, and amorphous carbon. The physical properties of carbon vary widely with the allotropic form, for example, graphite is opaque and black while diamond is highly transparent. Graphite is soft enough to form a streak on paper, while diamond is the hardest naturally occurring material known, graphite is a good electrical conductor while diamond has a low electrical conductivity. Under normal conditions, diamond, carbon nanotubes, and graphene have the highest thermal conductivities of all known materials, all carbon allotropes are solids under normal conditions, with graphite being the most thermodynamically stable form. They are chemically resistant and require high temperature to react even with oxygen, the most common oxidation state of carbon in inorganic compounds is +4, while +2 is found in carbon monoxide and transition metal carbonyl complexes. The largest sources of carbon are limestones, dolomites and carbon dioxide, but significant quantities occur in organic deposits of coal, peat, oil. For this reason, carbon has often referred to as the king of the elements. The allotropes of carbon graphite, one of the softest known substances, and diamond. It bonds readily with other small atoms including other carbon atoms, Carbon is known to form almost ten million different compounds, a large majority of all chemical compounds. Carbon also has the highest sublimation point of all elements, although thermodynamically prone to oxidation, carbon resists oxidation more effectively than elements such as iron and copper that are weaker reducing agents at room temperature. Carbon is the element, with a ground-state electron configuration of 1s22s22p2. Its first four ionisation energies,1086.5,2352.6,4620.5 and 6222.7 kJ/mol, are higher than those of the heavier group 14 elements. Carbons covalent radii are normally taken as 77.2 pm,66.7 pm and 60.3 pm, although these may vary depending on coordination number, in general, covalent radius decreases with lower coordination number and higher bond order. Carbon compounds form the basis of all life on Earth
3.
Milk
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Milk is a pale liquid produced by the mammary glands of mammals. It is the source of nutrition for infant mammals before they are able to digest other types of food. Early-lactation milk contains colostrum, which carries the mothers antibodies to its young and it contains many other nutrients including protein and lactose. As an agricultural product, milk is extracted from non-human mammals during or soon after pregnancy, Dairy farms produced about 730 million tonnes of milk in 2011, from 260 million dairy cows. India is the worlds largest producer of milk, and is the leading exporter of skimmed milk powder, the ever increasing rise in domestic demand for dairy products and a large demand-supply gap could lead to India being a net importer of dairy products in the future. The United States, India, China and Brazil are the worlds largest exporters of milk and milk products, China and Russia were the worlds largest importers of milk and milk products until 2016 when both countries became self-sufficient, contributing to a worldwide glut of milk. Throughout the world, there are more than six billion consumers of milk and milk products, over 750 million people live in dairy farming households. The term milk comes from Old English meoluc, milc, from Proto-Germanic *meluks milk, there are two distinct types of milk consumption, a natural source of nutrition for all infant mammals and a food product for humans of all ages that is derived from other animals. In almost all mammals, milk is fed to infants through breastfeeding, the early milk from mammals is called colostrum. Colostrum contains antibodies that provide protection to the baby as well as nutrients. The makeup of the colostrum and the period of secretion varies from species to species, for humans, the World Health Organization recommends exclusive breastfeeding for six months and breastfeeding in addition to other food for at least two years. In some cultures it is common to breastfeed children for three to five years, and the period may be longer, fresh goats milk is sometimes substituted for breast milk. This introduces the risk of the child developing electrolyte imbalances, metabolic acidosis, megaloblastic anemia, in many cultures of the world, especially the West, humans continue to consume milk beyond infancy, using the milk of other animals as a food product. Initially, the ability to digest milk was limited to children as adults did not produce lactase, Milk was therefore converted to curd, cheese and other products to reduce the levels of lactose. Thousands of years ago, a chance mutation spread in human populations in Europe that enabled the production of lactase in adulthood and this allowed milk to be used as a new source of nutrition which could sustain populations when other food sources failed. Milk is processed into a variety of products such as cream, butter, yogurt, kefir, ice cream. Modern industrial processes use milk to produce casein, whey protein, lactose, condensed milk, powdered milk, whole milk, butter and cream have high levels of saturated fat. The sugar lactose is found only in milk, forsythia flowers, the enzyme needed to digest lactose, lactase, reaches its highest levels in the small intestine after birth and then begins a slow decline unless milk is consumed regularly
4.
Starch
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Starch or amylum is a polymeric carbohydrate consisting of a large number of glucose units joined by glycosidic bonds. This polysaccharide is produced by most green plants as an energy store and it is the most common carbohydrate in human diets and is contained in large amounts in staple foods such as potatoes, wheat, maize, rice, and cassava. Pure starch is a white, tasteless and odorless powder that is insoluble in water or alcohol. It consists of two types of molecules, the linear and helical amylose and the branched amylopectin, depending on the plant, starch generally contains 20 to 25% amylose and 75 to 80% amylopectin by weight. Glycogen, the store of animals, is a more branched version of amylopectin. In industry, starch is converted into sugars, for example by malting and it is processed to produce many of the sugars used in processed foods. Dissolving starch in water gives wheatpaste, which can be used as a thickening, stiffening or gluing agent. The biggest industrial non-food use of starch is as an adhesive in the papermaking process, starch can be applied to parts of some garments before ironing, to stiffen them. The word starch is from a Germanic root with the strong, stiff. Amylum for starch is from the Greek αμυλον, amylon which means not ground at a mill, the root amyl is used in biochemistry for several compounds related to starch. Starch grains from the rhizomes of Typha as flour have been identified from grinding stones in Europe dating back to 30,000 years ago, starch grains from sorghum were found on grind stones in caves in Ngalue, Mozambique dating up to 100,000 years ago. Pure extracted wheat starch paste was used in Ancient Egypt possibly to glue papyrus, the extraction of starch is first described in the Natural History of Pliny the Elder around AD 77–79. Romans used it also in cosmetic creams, to powder the hair, persians and Indians used it to make dishes similar to gothumai wheat halva. Rice starch as surface treatment of paper has been used in production in China. In addition to starchy plants consumed directly,66 million tonnes of starch were being produced per year world-wide by 2008. In the EU this was around 8.5 million tonnes, with around 40% being used for applications and 60% for food uses. Most green plants use starch as their energy store, an exception is the family Asteraceae, where starch is replaced by the fructan inulin. In photosynthesis, plants use light energy to produce glucose from carbon dioxide, the glucose is used to make cellulose fibers, the structural component of the plant, or is stored in the form of starch granules, in amyloplasts
5.
Sucrose
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Sucrose is a common saccharide found in many plants and plant parts. Saccharose is a term for sugars in general, especially sucrose. The molecule is a combination of the monosaccharides glucose and fructose with the formula C12H22O11. Sucrose is often extracted and refined from either sugarcane or beet sugar for human consumption, modern industrial sugar refinement processes often involve bleaching and crystallization, producing a white, odorless, crystalline powder with a sweet taste of pure sucrose. This refined form of sucrose is commonly referred to as sugar or just sugar. It plays a role as an additive in food production all over the world. About 175 million metric tons of sucrose were produced worldwide in 2013, the term sucrose was first used in 1857 by English chemist William Miller from the French sucre and the generic chemical suffix for sugars -ose. The abbreviated term Suc is often used for sucrose in scientific literature, in sucrose, the components glucose and fructose are linked via an acetal bond between C1 on the glucosyl subunit and C2 on the fructosyl unit. The bond is called a glycosidic linkage, glucose exists predominantly as two isomeric pyranoses, but only one of these forms links to the fructose. Fructose itself exists as a mixture of furanoses, each of which having α and β isomers and this linkage inhibits further bonding to other saccharide units. Since it contains no anomeric hydroxyl groups, it is classified as a non-reducing sugar. Sucrose crystallizes in the space group P21 with room-temperature lattice parameters a =1.08631 nm, b =0.87044 nm, c =0.77624 nm. The purity of sucrose is measured by polarimetry, through the rotation of plane-polarized light by a solution of sugar, the specific rotation at 20 °C using yellow sodium-D light is +66. 47°. Commercial samples of sugar are assayed using this parameter, Sucrose does not deteriorate at ambient conditions. The formula for sucrose decomposition can be represented as a 2 step reaction, C12H22O11 + heat → 12C + 11H2O 12C + 12O2 → 12CO2 Sucrose does not melt at high temperatures. Instead, it decomposes—at 186 °C —to form caramel, like other carbohydrates, it combusts to carbon dioxide and water. Mixing sucrose with the potassium nitrate produces the fuel known as rocket candy that is used to propel amateur rocket motors. C12H22O11 +6 KNO3 →9 CO +3 N2 +11 H2O +3 K2CO3 This reaction is somewhat simplified though, some of the carbon does get fully oxidized to carbon dioxide, and other reactions, such as the water-gas shift reaction also take place
6.
Alkane
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In organic chemistry, an alkane, or paraffin, is an acyclic saturated hydrocarbon. In other words, an alkane consists of hydrogen and carbon atoms arranged in a structure in which all the carbon-carbon bonds are single. Alkanes have the chemical formula CnH2n+2. The alkanes range in complexity from the simplest case of methane, CH4 where n =1, in an alkane, each carbon atom has 4 bonds, and each hydrogen atom is joined to one of the carbon atoms. The longest series of linked carbon atoms in a molecule is known as its skeleton or carbon backbone. The number of atoms may be thought of as the size of the alkane. One group of the alkanes are waxes, solids at standard ambient temperature and pressure. They can be viewed as molecular trees upon which can be hung the more functional groups of biological molecules. The alkanes have two main sources, petroleum and natural gas. Saturated hydrocarbons are hydrocarbons having only single covalent bonds between their carbons, according to the definition by IUPAC, the former two are alkanes, whereas the third group is called cycloalkanes. Saturated hydrocarbons can also combine any of the linear, cyclic and branching structures, the formula is CnH 2n−2k+2. Alkanes are the ones, corresponding to k =0. Alkanes with more than three carbon atoms can be arranged in different ways, forming structural isomers. The simplest isomer of an alkane is the one in which the atoms are arranged in a single chain with no branches. This isomer is called the n-isomer. However the chain of atoms may also be branched at one or more points. The number of possible isomers increases rapidly with the number of carbon atoms, for example, 3-methylhexane and its higher homologues are chiral due to their stereogenic center at carbon atom number 3. In addition to the alkane isomers, the chain of atoms may form one or more loops
