Pitahaya

Selenicereus undatus, the white-fleshed pitahaya, belongs to the family Cactaceae and is the most cultivated species of its genus. In 2017, the genus Hylocereus was brought into synonymy with Selenicereus.

The plant climbs by aerial roots and can reach a height of 10 meters or more, growing on rocks and trees. The flowers are scented and nocturnal. The fruit is oblong to oval and red, with white or, more uncommonly, pink pulp and edible black seeds. Besides S. undatus, S. costaricensis has red-skinned fruit with red flesh and S. megalanthus has yellow-skinned fruit with white flesh. The red and purple colors of some Selenicereus fruits are due to betacyanins, a family of pigments that includes betanin.

Origin and Production

Selenicereus undatus is native from Mexico to Honduras. By the turn of the 21st century, the cultivation of dragon fruit had expanded to other regions including China, Colombia, and most of Southeast Asia. Substantial dragon fruit cultivation occurs in Vietnam, China, Mexico, Colombia, several countries of Southeastern Asia, and Australia. Colombia grows Selenicereus megalanthus, and Vietnam produces Selenicereus undatus. The formation of the fruit from pollination to harvest takes 4 to 8 weeks, depending on the temperatures.

Chemistry and Scent Profile

In two pitaya species studied in Turkey, 51 volatile compounds were detected, more of them in the white-fleshed species. In the samples tested there, the volatiles of the flesh were complex mixtures of many components. In six Hylocereus cultivars grown in California, aldehydes accounted for more than 90% of the total volatile amount. The seed oils of red-fleshed and white-fleshed pitaya are similar in fatty acid composition, mainly oleic acid (22%) and linoleic acid (50%).

Culinary Uses

When halved, a raw dragon fruit can be eaten with a spoon. The flowers can be eaten as a vegetable. The juice serves to give flavor and color to drinks, pastries and sweets. The fruit is eaten fresh or made into juice, jellies, marmalades, jams, wine and other beverages. Raw dragon fruit is 84% water and 15% carbohydrates, with negligible protein and fat.