The juice vesicles, also known as citrus kernels, of a citrus fruit are the membranous content of the fruit's endocarp. The vesicles contain the juice of the fruit and appear shiny and sacklike. Vesicles come in two shapes: the superior and inferior, and these are distinct. Citrus fruit with more vesicles generally weighs more than those with fewer vesicles. Fruits with many segments, such as the grapefruit or pomelo, have more vesicles per segment than fruits with fewer segments, such as the kumquat and mandarin. Each vesicle in a segment in citrus fruits has approximately the same shape, size, and weight. About 5% of the weight of an average orange is made up of the membranes of the juice vesicles.
A single juice vesicle of a lime.
A segment of an orange that has been opened to show its pulp.
Juice vesicles of a finger lime.
Citrus is a genus of flowering trees and shrubs in the rue family, Rutaceae. Plants in the genus produce citrus fruits, including crops such as oranges, mandarins, lemons, grapefruits, pomelos, and limes. The genus Citrus is native to South Asia, East Asia, Southeast Asia, Melanesia, and Australia. Various citrus species have been used and domesticated by indigenous cultures in these areas since ancient times. From there its cultivation spread into Micronesia and Polynesia by the Austronesian expansion ; and to the Middle East and the Mediterranean via the incense trade route, and onwards to Europe and the Americas.
Citrus
Slices of various citrus fruits
Lemons are a citrus fruit native to Asia, but now common worldwide.
Mediterranean Mandarin (Citrus ×deliciosa plantation, Son Carrió (Mallorca)