Averrhoa Carambola
Carambola, or star fruit, or Birambi is the fruit of Averrhoa carambola, a species of tree native to tropical Southeast Asia. The tree is cultivated throughout tropical areas.
The fruit has distinctive ridges running down its sides (usually 5–6). When cut in cross-section, it resembles a star, giving its name as star fruit. The entire fruit is edible, usually raw, and may be cooked or made into relishes, preserves, garnish, and juices.
The carambola tree has a short trunk with many branches, reaching up to 30 feet (9.1 m) in height. Its deciduous leaves are 6–10 inches (15–25 cm) long, with 5 to 11 ovate leaflets medium-green in colour. Flowers are lilac in colour, with purple streaks, and are about 0.25 inches (6.4 mm) wide.
The showy fruits have a thin, waxy pericarp, orange-yellow skin, and crisp, yellow flesh with juice when ripe. The fruit is about 5 to 15 centimetres (2 to 6 inches) in length and is an oval shape. It usually has five or six prominent longitudinal ridges. In cross section, it resembles a star. The flesh is translucent and light yellow to yellow in colour. Each fruit can have 10 to 12 flat light brown seeds about 6 to 13 mm (0.25 to 0.5 in) in width and enclosed in gelatinous aril. Once removed from the fruit, they lose viability within a few days.
Like the closely related bilimbi, there are two main types of carambola: the small sour (or tart) type and the larger sweet type. The sour varieties have a higher oxalic acid content than the sweet type. A number of cultivars have been developed in recent years.