Averrhoa carambola

starfruit

Carambola, or starfruit, gets its popular English common name from the shape of the slices in cross-section. Usually used to garnish fruit salads and desserts, starfruit can be delicious on its own if you find the right variety. One variety is smaller and richly flavored but has more oxalic acid and less sugar than the other, larger, more mildly-flavored variety. We have the latter variety at Kona Kai and although it may be somewhat bland when just ripe, if you wait until the fruit is dark yellow, you will be rewarded with a flavorful treat. Some describe the flavor as being a cross between an apple and a grape.

Originating in Sri Lanka and the Moluccas or Spice Islands, starfruit has been cultivated in Southeast Asia and Malaysia for centuries, reaching the US in the late 1800s. It is not to be confused with Averrhoa bilimbi or cucumber tree which is smaller and much more tart with high levels of oxalic acid. Oxalic acid is formed when the saliva in your mouth hits the calcium oxalate crystals in the fruit and you taste a pop of tartness. People with impaired kidney function should stay away from starfruit and its juice as the oxalate crystals and an unknown toxin can induce “starfruit intoxication” which could be lethal; the only known treatment for this condition is prompt dialysis. Symptoms of "starfruit intoxication" include persistent hiccups, nausea, vomiting, agitation, insomnia, mental confusion and convulsions that occur within one to five hours of eating the fruit or juice.

The fruit may be eaten out of hand without peeling or seeding; used in chutney, jams, jellies, curries and tarts; pickled, dried, stewed with sugar and cloves, canned, and juiced for use in smoothies or bottled. The flowers and leaves are edible, as well. Other uses of the more acidic variety include cleaning and polishing metal and use as a mordant in dyeing. The wood is used in construction and furniture. There are numerous medicinal uses for the ripe and dried fruit, flowers and seeds, leaves, shoots, and roots. Preparations of the leaves and roots have been used to cure headaches, hangovers, vomiting, sore eyes, prickly heat, chickenpox and ringworm. The flowers may act as a vermifuge and may be used to counteract dermatitis from Rhus species – poison ivy and its relatives. A decoction of the crushed seeds my be given to nursing mothers to stimulate the flow of milk and powdered seeds may help with symptoms of asthma and colic.