Also called corossol, graviola, guanabana, guanábana and sirsak, the soursop is native to the tropical regions of the Caribbean and Central and South America. It's also grown in tropical areas in Africa, Southeast Asia and Australia, and to a limited extent in southern Florida. Belonging to the genus Annona, the soursop (A. muricata) is one of several members of the Annona family, which also includes the cherimoya and sweetsop. This large tropical fruit can weigh 6 pounds or more and be up to 12 inches long and 6 inches wide. The soursop has a green, leathery skin that's covered with prickly spines. Its flesh is creamy white, peppered with brownish-black seeds and has a tropical fruit flavor that's slightly more acidic than other members of its family. Depending on the region, fresh soursop can be available year-round, typically found in Latin and specialty produce markets. Purchase fruit that's firm, heavy for its size and without skin blemishes; avoid those with brown splotching. Store at room temperature until ripe (they'll give slightly with soft pressure), then refrigerate, well wrapped, for up to a week. Soursop pulp is processed into juice, ice cream, sorbet and candy. Pulp in syrup is sometimes available in ethnic markets. Soursops contain a fair amount of niacin, iron, potassium and vitamins B1, B2 and C.
From The Food Lover's Companion, Fourth edition by Sharon Tyler Herbst and Ron Herbst. Copyright © 2007, 2001, 1995, 1990 by Barron's Educational Series, Inc.