The papaya is sometimes called papaw or pawpaw, but in the United States these names are generally restricted to Asimina triloba (L.) Dunal (see "Papaw"). Papayas are grown to a limited extent in continental United States. They have been tried in Texas and in California, have never exceeded a few hundred acres even in Florida (Harkness 1967), but are more common in Hawaii and Puerto Rico. The 1964 United States Census of Agriculture showed that 32 farms in Florida produced almost 1.5 million pounds of fruit, while 266 farms in Hawaii produced almost 22 million pounds.
Papayas grow from about 32 deg N. to 32 deg S. latitude, from sea level to 5,000 feet altitude. They are killed by frost but do well in full sun or under irrigation. They do not occur in the wild, probably originated in Mexico or Costa Rica, and now consist of many cultivars (Purseglove 1968*).
The ripe fresh fruit (90 percent water, 4 to 10 percent sugar) (Wolfe and Lynch 1940) is eaten throughout the tropics for breakfast, dessert, in salads, jams, ice creams, and soft drinks. The dried latex or "milk" of immature fruit yields papain, a proteolytic enzyme similar in action to pepsin, which is used as a meat tenderizer (Becker 1958). It also creates shrink-resistance in wool.