C. × paradisi
|Citrus × paradisi|
The grapefruit (Citrus × paradisi) is a subtropical citrus tree known for its relatively large sour to semisweet, somewhat bitter fruit. Grapefruit is a citrus hybrid originating in Barbados as an accidental cross between the sweet orange (C. sinensis) and the pomelo, aka, shaddock (C. maxima), both of which were introduced from Asia in the 17th century. When found, it was nicknamed the "forbidden fruit". In the past it was referred to as the "pomelo", but that term is now the common name for the shaddock (Citrus maxima), which is also called the "pummelo".
It is believed that the name refers to the manner in which grapefruit grows in clusters on a tree.. The interior flesh is segmented and varies in color from white to yellow to pink to red.
The evergreen grapefruit trees usually grow to around 5-6 m (16-20 ft) tall, although they may reach 13-15 m (43-49 ft). The leaves are glossy, dark green, long (up to 15 cm (5.9 in)), and thin. It produces 5 cm (2 in) white four-petaled flowers. The fruit is yellow-orange skinned and generally, an oblate spheroid in shape; it ranges in diameter from 10 to 15 cm (3.9 to 5.9 in). The flesh is segmented and acidic, varying in color depending on the cultivars, which include white, pink, and red pulps of varying sweetness (generally, the redder varieties are the sweetest). The 1929 U.S. Ruby Red (of the 'Redblush' variety) has the first grapefruit patent.
The genetic origin of the grapefruit is a hybrid mix. One ancestor of the grapefruit was the Jamaican sweet orange (Citrus sinensis), itself an ancient hybrid of Asian origin; the other was the Indonesian shaddock (C. maxima). One story of the fruit's origin is that a certain "Captain Shaddock" brought pummelo (Citrus maxima) seeds to Jamaica and bred the first fruit, which were then called shaddocks. This apparently referred to a Captin Chaddock who traded in the West Indies in the 17th century. The grapefruit then probably originated as a naturally occurring hybrid between the two plants some time after they had been introduced there.
The Trunk, Leaves, and Flowers of this Tree, very much resemble
those of the Orange-tree.
The Fruit, when ripe, is something longer and larger than the largest
Orange; and exceeds, in the Delicacy of its Taste, the Fruit of every
Tree in this or any of our neighbouring Islands.
It hath somewhat of the Taste of a Shaddock; but far exceeds that, as
well as the best Orange, in its delicious Taste and Flavour.
--Description from Hughes' 1750 Natural History of Barbados
The hybrid fruit, then called "the forbidden fruit", was first documented in 1750 by a Welshman, Rev. Griffith Hughes, who described specimens from Barbados in The Natural History of Barbados. Currently, the grapefruit is said to be one of the "Seven Wonders of Barbados".
The grapefruit was known as "forbidden fruit" until 1814, when naturalist John Lunan first recorded it as "grapefruit". Its current name may allude to clusters of the fruit on the tree, which often appear similar to those of grapes. In the 1830s it was given the botanical name Citrus paradisi. The name "grape-fruit" was used more and more during the 19th century instead of "pomelo", to the consternation of some.
The grapefruit was brought to Florida by Count Odet Philippe in 1823, in what is now known as Safety Harbor. Further crosses have produced the tangelo (1905), the Minneola tangelo (1931), and the oroblanco (1984).
An early pioneer in the American citrus industry was Kimball 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. There, pink grapefruit was first discovered in 1906.
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.Using radiation to trigger mutations, new varieties were developed to retain the red tones that typically faded to pink. The 'Rio Red' variety is 2007 Texas grapefruit with registered trademarks Rio Star and Ruby-Sweet, also sometimes promoted as Reddest and Texas Choice. The 'Rio Red' is a mutation-bred variety that was developed by treatment of bud sticks with thermal neutrons. Its improved attributes of mutant variety are fruit and juice color, deeper red, and wide adaptation.
The 'Star Ruby' is the darkest of the red varieties. Developed from an irradiated 'Hudson' grapefruit, it has found limited commercial success because it is more difficult to grow than other varieties.
|Grapefruit production in 2018|
(millions of tonnes)
|Source: FAOSTAT of the United Nations|
Grapefruit varieties are differentiated by the flesh color of fruit they produce. Common varieties are red, white, and pink pulp colors. Flavors range from highly acidic and somewhat sour to sweet and tart, resulting from composition of sugars (mainly sucrose), organic acids (mainly citric acid), and monoterpenes and sesquiterpenes providing aromas.
This happens in two very different ways. In the first, the effect is from bergamottin, a natural furanocoumarin in both grapefruit flesh and peel that inhibits the CYP3A4 enzyme (among others from the P450 enzyme family responsible for metabolizing 90% of drugs). The action of the CYP3A4 enzyme itself is to metabolize many medications. If the drug's breakdown for removal is lessened, then the level of the drug in the blood may become too high or stay too long, leading to adverse effects. On the other hand, some drugs must be broken down to become active, and inhibiting CYP3A4 may lead to reduced drug effects.
The other effect is that grapefruit can block the absorption of drugs in the intestine. If the 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.
One whole grapefruit, or a glass of 200 ml (6.8 US fl oz) of grapefruit juice may cause drug overdose toxicity. Typically, drugs that are incompatible with grapefruit are so labeled on the container or package insert. People taking drugs should ask their health-care provider or pharmacist questions about grapefruit and drug interactions.
Raw grapefruit is 90% water, 8% carbohydrates, 1% protein, and negligible fat (table). In a 100-g reference amount, raw grapefruit provides 33 Calories and is a rich source of vitamin C (40% of the Daily Value), with no other micronutrients in significant content.
In Costa Rica, especially in Atenas, grapefruit are often cooked to remove their sourness, rendering them as sweets; they are also stuffed with dulce de leche, resulting in a dessert called toronja rellena (stuffed grapefruit). In Haiti, grapefruit is used primarily for its juice (jus de Chadèque), but also is used to make jam (confiture de Chadèque).
Grapefruits are one of the most common hosts for fruit flies such as A. suspensa, which lay their eggs in overripe or spoiled grapefruits. The larvae of these flies then consume the fruit to gain nutrients until they can proceed into the pupae stage. This parasitism has led to millions in economic costs for nations in Central America and southern North America.
Grapefruit has also been investigated in cancer medicine pharmacodynamics. Its inhibiting effect on the metabolism of some drugs may allow smaller doses to be used, which can help to reduce costs.
The grapefruit is a parent to many hybrids:
Related citrus fruits include:
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 shaddock (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' in The 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, since George 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 1837 Flora 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.
The Development of the Gully - The Gully was once part of a plantation owned by a Welshman called General William Asygell Williams over 200 years ago. Hence the name "Welchman Hall" gully. It was this man who first developed the gully with exotic trees and an orchard. Interestingly, the grapefruit is originally from Barbados and is rumoured to have started in Welchman Hall Gully.
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 name pomelo, which is popular, and botanically correct.