Pomelo

The pomelo tree can be 5–15 metres (16–50 feet) tall, with a trunk, often rather crooked, that is 10–30 centimetres (4–12 inches) thick, and low-hanging, irregular branches. The petioles (leaf stalks) are distinctly winged. The leaves are alternate, ovate or elliptic in shape, and 5–20 cm (2–8 in) long; they are leathery and dull green above, hairy beneath. The flowers, produced singly or in clusters, are fragrant and yellow-white. The fruit is large, 10–30 cm (4–12 in) in diameter, round or somewhat pear-shaped. Its weight varies by cultivar from 0.26–1.95 kilograms (0.6–4.3 pounds). It has a thicker peel than a grapefruit, and is divided into 11 to 18 segments. The flesh is less acidic than that of the grapefruit. The pomelo has at least sixty cultivars. The fruit generally contains a few, relatively large seeds, but some cultivars have numerous seeds. The characteristics of pomelo vary widely across South Asia. The pomelo is native to Southeast Asia and all of Malaysia. The tree may have been introduced to China around 100 BCE, and is now heavily cultivated in Southern China. Seeds of the tree were first brought to the Americas in the late 1600s.

The pomelo, while not itself toxic, can cause adverse interactions similar to those caused by the grapefruit with a wide range of prescription drugs. These occur by the inhibition of cytochrome P450-mediated metabolism of prescription drugs including for example some anti-hypertensives, some anticoagulants, some anticancer agents, some anti-infective agents, some statins, and some immunosuppressants.

Raw pomelo flesh is 89% water, 10% carbohydrates, 1% protein, and contains negligible fat. A 100-gram reference amount provides 159 kilojoules (38 kilocalories) of food energy, and is rich in vitamin C (68% of the Daily Value), with no other micronutrients in significant content (table).

The seeds of the pomelo are monoembryonic, producing seedlings with genes from both parents, so they do not breed true to type. However, they are usually fairly similar to the tree they grow from and therefore in Asia, pomelos are typically grown from seed. Seeds can be stored for 80 days at a temperature of 5 °C (41 °F) with moderate relative humidity. Pomelos can be propagated vegetatively by air-layering, by taking cuttings, by grafting, by shield budding, or by tissue culture.

According to the Oxford English Dictionary, the etymology of the word "pomelo" is uncertain. It may be derived from Dutch pompelmoes. The Dutch name in turn has uncertain etymology, but is possibly derived from Dutch pompel ("swollen") or pompoen ("pumpkin"), combined with limoes ("lemon, citrus fruit"), influenced by Portuguese limões with the same meaning. An alternative possibility is that the Dutch name derives from Portuguese pomos limões ("citrus fruit"). The specific name maxima is the feminine form of the Latin word meaning "biggest". One theory for the alternative English name "shaddock" is that it was adopted after the plant's introduction into Barbados by a "Captain Shaddock" of the East India Company (apparently Philip Chaddock, who visited the island in the late 1640s). From there the name spread to Jamaica in 1696.