There are several species of citrus trees whose fruits are called limes, including the Key lime (Citrus aurantiifolia), Persian lime, kaffir lime, and desert lime. Limes are a rich source of vitamin C, are sour, and are often used to accent the flavours of foods and beverages. They are grown year-round. Plants with fruit called "limes" have diverse genetic origins; limes do not form a monophyletic group.
Plants known as "lime"
The difficulty in identifying exactly which species of fruit are called lime in different parts of the English-speaking world (and the same problem applies to homonyms in other European languages) is increased by the botanical complexity of the citrus genus itself, to which the majority of limes belong. Species of this genus hybridise readily, and it is only recently that genetic studies have started to shed light on the structure of the genus. The majority of cultivated species are in reality hybrids, produced from the citron (Citrus medica), the mandarin orange (Citrus reticulata), the pomelo (Citrus maxima) and in particular with many lime varieties, the micrantha (Citrus micrantha).
To prevent scurvy during the 19th century, British sailors were issued a daily allowance of citrus, such as lemon, and later switched to lime. The use of citrus was initially a closely guarded military secret, as scurvy was a common scourge of various national navies, and the ability to remain at sea for lengthy periods without contracting the disorder was a huge benefit for the military. British sailors thus acquired the nickname "Limey" because of their use of limes.
In 2018, world production of limes (combined with lemons for reporting) was 19.4 million tonnes. The top producers – India, Mexico, China, Argentina, Brazil, and Turkey – collectively accounted for 65% of global production (table).
Limes have higher contents of sugars and acids than lemons do. Lime juice may be squeezed from fresh limes, or purchased in bottles in both unsweetened and sweetened varieties. Lime juice is used to make limeade, and as an ingredient (typically as sour mix) in many cocktails.
Raw limes are 88% water, 10% carbohydrates and less than 1% each of fat and protein (table). Only vitamin C content at 35% of the Daily Value (DV) per 100 g serving is significant for nutrition, with other nutrients present in low DV amounts (table). Lime juice contains slightly less citric acid than lemon juice (about 47 g/l), nearly twice the citric acid of grapefruit juice, and about five times the amount of citric acid found in orange juice.
Lime peel contains higher concentrations of furanocoumarins than lime pulp (by one or two orders of magnitude), and so lime peels are considerably more phototoxic than lime pulp. Persian limes appear to be more phototoxic than Key limes.
^Loizzo MR, Tundis R, Bonesi M, Menichini F, De Luca D, Colica C, Menichini F (2012). "Evaluation of Citrus aurantifolia peel and leaves extracts for their chemical composition, antioxidant and anti-cholinesterase activities". J Sci Food Agric. 92 (15): 2960-67. doi:10.1002/jsfa.5708. PMID22589172.CS1 maint: uses authors parameter (link)
^ abcWagner, A. M.; Wu, J. J.; Hansen, R. C.; Nigg, H. N.; Beiere, R. C. (2002). "Bullous phytophotodermatitis associated with high natural concentrations of furanocoumarins in limes". Am J Contact Dermat. 13 (1): 10-14. doi:10.1053/ajcd.2002.29948. ISSN0891-5849. PMID11887098.