Thegrapefruit (Citrus ×paradisi) is a subtropicalcitrus tree known for its relatively large,sour to semi-sweet, somewhatbitter fruit.[1] The flesh of the fruit is segmented and varies in color from pale yellow to dark red.
Grapefruits originated inBarbados in the 18th century. They are a citrushybrid that was created through an accidental cross between thesweet orange (C. ×sinensis) and thepomelo (C. maxima), both of which were introduced to the Caribbean from Asia in the 17th century.[2] It has also been called the 'forbidden fruit'.[1] In the past it was called thepomelo,[3] but that term is now mostly used as the common name forCitrus maxima.[4]
Grapefruit–drug interactions are common, as the juice containsfuranocoumarins that interfere with the metabolism of many drugs. This can prolong and intensify the effects of those drugs, leading to multiple side-effects such as abnormal heart rhythms, bleeding inside the stomach, low blood pressure, difficulty breathing, and dizziness.
Grapefruit growing in the grape-like clusters from which their name may derive
The evergreen grapefruit trees usually grow to around 4.5–6 m (15–20 ft) tall, although they may reach 13.7 m (45 ft).[1] The leaves are up to 15 cm (6 in) long, thin, glossy, and dark green. They produce 5 cm (2 in) white flowers with four or five petals. The fruit is yellow-orange skinned and generally anoblate spheroid in shape; it ranges in diameter from 10 to 15 cm (4 to 6 in). Its flesh is segmented and acidic, varying in color depending on thecultivars, which include white, pink, and red pulps of varying sweetness (generally, the redder varieties are the sweetest).[1]
White grapefruit varieties include Camulos, Cecily, Duncan, Frost Marsh, Genetic Dwarf Marsh, Hall, Jochimsen, Marsh seedy, Nicholson navel, Perlis, Reed Marsh, Tetraploid, Warren Marsh, and Whitney Marsh.[5]
Red or pink grapefruit varieties include Flame, Foster Pink, Henderson Ruby, Hudson Foster, Marsh Pink, Ray Ruby, Redblush, Rio Red, Shambar, and Star Ruby.[6]
The 1929 'Ruby Red' (or 'Redblush') patent was associated with real commercial success, which came after the discovery of a red grapefruit growing on a pink variety.[1] TheTexas Legislature designated this variety the official "State Fruit of Texas" in 1993.[7]
Usingradiation to trigger mutations, new varieties were developed to retain the red tones that typically faded to pink.[8] The 'Rio Red' variety is a 1984 registered Texas grapefruit with registered trademarksRio Star andRuby-Sweet, also sometimes promoted asReddest andTexas Choice. The 'Rio Red' is amutation-bred variety that was developed by treatment of bud sticks withthermal neutrons. Its improved attributes of mutant variety are fruit and juice color, deeper red, and wide adaptation.[9]
The 'Star Ruby' is the darkest of the red varieties.[1] Developed from an irradiated 'Hudson' grapefruit ('Hudson' being a limb sport of 'Foster', itself a limb sport of the 'Walters'),[10] it has found limited commercial success because it is more difficult to grow than other varieties.[11][12]
Raw white grapefruit is 90% water, 8% carbohydrates, 1% protein, and contains negligible fat (table). In a reference amount of 100 grams (3+1⁄2 ounces), raw grapefruit provides 138 kilojoules (33 kilocalories) offood energy and is a rich source ofvitamin C (37% of theDaily Value), with no othermicronutrients in significant amounts (table).
Like other citrus fruits, grapefruits are sour because of theircitric acid content; grapefruit juice contains about half the citric acid content of lemon juice, and nearly 50% more than orange juice.[15] In Costa Rica, especially inAtenas, grapefruit are often cooked with sugar to balance their sourness, rendering them assweets; or they are stuffed withdulce de leche as adessert.[16] In Haiti, grapefruit is used primarily for its juice (jus de Chadèque), but also is used to make jam (confiture de Chadèque).[17][18]
Grapefruit varieties are differentiated by the flesh color of fruit they produce. Common varieties are yellow and pink pulp colors. Flavors range from highly acidic and somewhat sour to sweet and tart, resulting from composition of sugars (mainlysucrose), organic acids (mainly citric acid), andmonoterpenes andsesquiterpenes providing aromas.[19]Grapefruit mercaptan, asulfur-containingterpene, is one of thearoma compounds influencing the taste and odor of grapefruit, compared with other citrus fruits.[20]
One interaction occurs from grapefruitfuranocoumarins, such asbergamottin and6',7'-dihydroxybergamottin, which occur in both flesh and peel. Furanocoumarins inhibit theCYP3A4enzyme (among others from thecytochrome P450 enzyme family responsible for metabolizing 90% of drugs).[22] The action of the CYP3A4 enzyme itself is to metabolize many medications.[23] If a drug's breakdown for removal is lessened, then the level of that drug in the blood may become and remain high, leading to adverse effects.[21] On the other hand, some drugs must be metabolized to become active, and inhibiting CYP3A4 may lead to reduced drug effects.[21]
Another effect is that grapefruit compounds may inhibit the absorption of drugs in the intestine. If a drug is not absorbed, then not enough of it is in the blood to have a therapeutic effect. Each affected drug has either a specific increase of effect or decrease.[24]
One whole grapefruit or a glass of 200 ml (7 US fl oz) of grapefruit juice is enough to cause drug overdose toxicity.[21] Typically, drugs that are incompatible with grapefruit are marked as such on the container orpackage insert.[21]
In 2022, world production of grapefruits (combined withpomelos) was 9.8 milliontonnes, led by China with 53% of the world total withVietnam as a secondary producer (table).
Grapefruits are hosts for fruit flies (familyTephritidae) such asA. suspensa, which lay their eggs in overripe or spoiled grapefruits, sometimes causing serious damage in plantations in the Americas.[26] In sub-Saharan Africa, the Citrus swallowtail,Papilio demodocus, is a minor pest ofCitrus plantations.[27] Grapefruits are subject to several diseases ofCitrus trees, includingcitrus tristeza virus,citrus canker (caused by a bacterium,Xanthomonas), and thevector-transmittedcitrus greening disease, where the vector is apsyllid bug, and the pathogen is a bacterium,Liberibacter.[28]
Grapefruit originated as a natural hybrid.[30] One ancestor of the grapefruit was the Jamaican sweet orange (Citrus sinensis), itself an ancient hybrid of Asian origin; the other was the Indonesianpomelo (C. maxima).[1] The pomelo was the female ancestor; the sweet orange, itself a hybrid, was the male.[29] BothC. sinensis andC. maxima were present in the West Indies by 1692. One story of the fruit's origin is that a 17th-century trader named 'Captain Shaddock'[1][31] brought pomelo seeds to Jamaica and bred the first fruit, which were then calledshaddocks.[32] The grapefruit then probably originated as a naturally occurring hybrid between the two plants some time after they had been introduced there.[1][2]
Kimball Chase Atwood founded the Atwood Grapefruit Company in the late 19th century. It became the largest grapefruit grove in the world.[33]
A hybrid fruit, calledforbidden fruit, was first documented in 1750 (along with 14 other citrus fruits including the guiney orange) by a Welshman, the Rev. Griffith Hughes, in hisThe Natural History of Barbados.[1] However, Hughes's forbidden fruit may have beena plant distinct from grapefruit although still closely related to it.[34]
In 1814, the British naturalist and plantation ownerJohn Lunan published the termgrapefruit to describe a similar Jamaican citrus plant.[32] Lunan reported that the name was due to its similarity in taste to the grape (Vitis vinifera).[35] An alternative explanation is that this name may allude to clusters of the fruit on the tree, which often appear similar to bunches of grapes.[36][37]
In 1830, the Jamaican version of the plant was given the botanical nameCitrus paradisi by the Scottish physician and botanistJames Macfadyen. Macfadyen identified two varieties – one calledforbidden fruit, the otherBarbadoes Grape Fruit. Macfadyen distinguished between the two plants by fruit shape with the Barbados grapefruit being piriform (pear shaped) while the forbidden fruit was "maliformis".[38] Macfadyen's and Hughes's descriptions differ, so it is not clear that the two reports are describing the same plant. It has been suggested that Hughes's golden orange may actually have been a grapefruit, while his forbidden fruit was a different variety that may since have been lost.[31] A citrus calledforbidden fruit orshaddette has been discovered inSaint Lucia; it may be the plant described by Hughes and Macfadyen.[34]
The namegrape-fruit was used during the 19th century to refer to pomelos.[36] It was brought to Florida by the French businessman CountOdet Philippe in 1823, in what is now known asSafety Harbor.[1] Further crosses have produced thetangelo (1905), theMinneola tangelo (1931), and theoroblanco (1984). Its true origins were not determined until the 1940s, at which point its official name was altered toCitrus ×paradisi, the× identifying it as a hybrid.[39] An early pioneer in the American citrus industry was Kimball C. Atwood, a wealthy entrepreneur who founded the Atwood Grapefruit Company in the late 19th century. The Atwood Grove became the largest grapefruit grove in the world, with a yearly output of 80,000 boxes of fruit.[33] There, pink grapefruit was discovered in 1906.[1]
^abCarrington, Sean; Fraser, Henry C. (2003). "Grapefruit".A~Z of Barbados Heritage. Macmillan Caribbean. pp. 90–91.ISBN978-0-333-92068-8.One of many citrus species grown in Barbados. This fruit is believed to have originated in Barbados as a natural cross between sweet orange (C. sinesis) and pomelo (C. grandis), both of which originated in Asia and were introduced by Europeans in the 17th century. The grapefruit first appeared as an illustration entitled 'The Forbidden Fruit Tree' inThe Natural History of Barbados (1750) by Rev. Griffith Hughes. This accords with the scientific name, which literally is 'citrus of paradise'. The fruit seems to have been fairly commonly available around that time, sinceGeorge Washington in his Barbados Journal (1750–1751) mentions 'the Forbidden Fruit' as one of the local fruit available at a dinner party he attended. The plant was later described in the 1837Flora of Jamaica as the Barbados Grapefruit. The historical arguments and experimental work on leaf enzymes and oils from possible parents all support a Barbadian origin for the fruit.
^Ben Box, ed. (1993). "Costa Rica - The Meseta Central".1994 Mexico & Central America Handbook. Sarah Cameron, Sebastian Ballard (4 ed.). Trade and Travel Publications. p. 682.ISBN978-0900751462.
^Bidault, Blandine; Gattegno, Isabelle, eds. (1984).Le point sur la transformation des fruits tropicaux [Update on the processing of tropical fruits] (in French). Paris: Groupe de recherche et d'echanges technologiques (GRET). p. 46.
^Zheng, Huiwen; Zhang, Qiuyun; Quan, Junping; Zheng, Qiao; Xi, Wanpeng (2016). "Determination of sugars, organic acids, aroma components, and carotenoids in grapefruit pulps".Food Chemistry.205:112–121.doi:10.1016/j.foodchem.2016.03.007.PMID27006221.S2CID41172984.
^Buettner, A.; Schieberle, P. (1999). "Characterization of the Most Odor-Active Volatiles in Fresh, Hand-Squeezed Juice of Grapefruit (Citrus paradisi Macfayden)".J. Agric. Food Chem.47 (12):5189–5193.Bibcode:1999JAFC...47.5189B.doi:10.1021/jf990071l.PMID10606593.
^Kakar, S.M.; Paine, M.F.; Stewart, P.W.; Watkins, P.B. (2004). "6',7'-Dihydroxybergamottin contributes to the grapefruit juice effect".Clinical Pharmacology and Therapeutics.75 (6):569–579.doi:10.1016/j.clpt.2004.02.007.hdl:2027.42/109773.PMID15179411.
^van Whervin, L. Walter (March 1974). "Some Fruitflies (Tephritidae) in Jamaica".Pest Articles & News Summaries.20 (1):11–19.doi:10.1080/096708774094123313 (inactive 29 December 2024).{{cite journal}}: CS1 maint: DOI inactive as of December 2024 (link)
^abKumamoto, J.; Scora, R. W.; Lawton, H. W.; Clerx, W. A. (1987-01-01). "Mystery of the forbidden fruit: Historical epilogue on the origin of the grapefruit, Citrus paradisi (Rutaceae)".Economic Botany.41 (1):97–107.Bibcode:1987EcBot..41...97K.doi:10.1007/BF02859356.S2CID42178548.
^Lunan, John (1814).Hortus Jamaicensis. Jamaica: St. Iago de la Vega Gazette. pp. 171–173.Archived from the original on 27 July 2020. Retrieved24 December 2020.
^abCalifornia (1895)."Report of the Secretary–the pomelo".Appendix to the Journals of the Senate and Assembly of the twenty-first Session of the Legislature of the State of California. Vol. V. Sacramento, California: Legislature of the State of California. p. 65.Archived from the original on 2023-07-13. Retrieved2020-10-07.The pomelo is now marketed under the name 'grape-fruit', which is a misnomer. This is confusing and misleading. The name 'grape-fruit' was given to this fruit in Florida, as it hangs on trees in clusters resembling the grape, but has no relation to it whatever. Growers and shippers should drop the name 'grape-fruit' and apply to it the namepomelo, which is popular, and botanically correct.