star fruit

Carambolas still on the tree

Carambola or starfruit is the fruit of Averrhoa carambola, a species of tree native to Indonesia, India and Sri Lanka. The tree and its fruit are popular throughout Southeast Asia, Malaysia, the South Pacific and other parts of East Asia. The tree is cultivated also throughout the tropics such as in Trinidad, Guyana, and Brazil, and, in the United States, in south Florida, and Hawaii.

The carambola is closely related to the bilimbi. The fruit in cross section is a five-pointed star, hence its name.

Origins and distribution

The carambola has been grown in parts of Asia for hundreds of years – some claim that it originated in Sri Lanka and Moluccas. Malaysia is the global leader in starfruit production by volume, and ships the product all over Asia and Europe.

Due to concerns on pests and pathogens, however, whole starfruits cannot yet be imported to the US from Malaysia, under current FDA/USDA regulation. In the United States, starfruits are grown in tropical and semi tropical areas, including Florida, Puerto Rico and Hawaii. ^[1][2][3][4]

Gastronomy

Starfruit and slices.

Carambolas are best consumed when ripe, when they are yellow with a light shade of green. It will also have brown ridges at the five edges and feel firm. An overripe fruit will be yellow with brown spots.

The fruit is entirely edible, including the slightly waxy skin. It is sweet without being overwhelming and extremely juicy. The taste is difficult to compare, but it has been likened to a mix of papaya, orange and grapefruit all at once.

Health benefits

Carambola is rich in antioxidants and vitamin C, and low in sugar, sodium and acid. It is also is a potent source of both primary and secondary polyphenolic antioxidants.^[5]

Health risks

Carambola is a fairly complex fruit with many benefits like strawberries, but a small percent of the human population should be cautious of the fruit for health reasons. Like the grapefruit, carambola contains oxalic acid which can be harmful to individuals suffering from kidney failure or under kidney dialysis treatment. Consumption by those with kidney failure can produce hiccups, vomiting, nausea, and mental confusion. Fatal outcomes have been documented in some patients.^{[6][7][8][9][10] [11]}

Drug interactions

Like the grapefruit, carambola is considered to be a potent inhibitor of seven cytochrome P450 isoforms.^[12][13] These enzymes are significant in the first pass elimination of many medicines, and thus the consumption of carambola or its juice in combination with certain medications can significantly increase their effective dosage within the body. Research into grapefruit juice has identified a number of common medications affected, including statins which are commonly used to treat cardiovascular illness, benzodiazepines (a tranquilizer family including diazepam) as well as other medicines.^[14].

Cultivation

The carambola is a tropical and subtropical fruit. In India, it grows in up to 4,000 feet in elevation. It prefers a total exposition to the sun, but requires enough humidity and a total of 70 inches or more of rainfall a year. It does not have a preference in grounds but it requires a good drainage.

Carambola trees are planted at least 20 feet from each other, and fertilized three times a year. The tree grows fast and produces food at 4 or 5 years of age, sometimes even before that. The large amount of rain during spring actually reduces the amount of fruit, but in ideal conditions carambola can produce from 200 to 400 pounds of fruit a year. The fruit is cultivated mainly during the months of June, July, and August, but sometimes year-round.

Major pests are fruit flies, ants, and birds. Crops are also susceptible to frosts, especially in the United States.

References