Q: I have a question about a fruit from St. Lucia. It is supposed to have cancer fighting properties and is delicious, according to my best friend. Her boyfriend is from St. Lucia and she has had the fruit there and wonders about what a good source would be to obtain it here in Connecticut. It is called soursap and is large, green and yellow and is white inside. Any help would be appreciated.
--Joanne Thompson Pease, Torrington, Conn.
A: Soursap, or soursop as it is listed in "The New Food Lover's Companion," is a tropical fruit grown in the Caribbean, Latin America, Africa and Southeast Asia. It's also known as corossol, graviola, guanabana, custard apple, Brazilian paw paw, among other names, according to various sources.
Soursop has been used in folk or traditional medicine in many countries, reports the "Integrative Medicine" page devoted to the fruit, listed there as "graviola," on the Memorial Sloan-Kettering Cancer Center website.
"Extracts of graviola show antiviral, antiparasitic, antirheumatic, astringent, emetic, antileishmanial and cytotoxic, antinociceptive, anti-inflammatory, antihyperglycemic and anticancer effects in vitro and in vivo. However, human data is lacking," reports the website for the New York City-based center, adding: "Alkaloids extracted from graviola may cause neuronal dysfunction and degeneration leading to symptoms of Parkinson's disease."
Before reaching for a medical dictionary to figure that all out, consider this from Colleen Doyle, director of nutrition and physical activity for the American Cancer Society, who wrote in an e-mail that there's been "a lot of talk" about the fruit, "as well as in the bark, leaves and root of the tree on which it grows, being effective in helping to treat cancer, but the jury is still out on that."
"A few lab studies have been conducted that suggest that extracts of the fruit may kill some types of cancer cells, but at this point in time, there is no evidence from human studies that consuming soursop — or supplements made from it — is beneficial for treating cancer," she wrote from the society's Atlanta office. "So while it's delicious and can certainly be part of a healthy diet, it should not be used as an alternative to known, effective cancer treatments"
So, where can you find soursop to enjoy in a culinary way? Your best bet in finding a fresh one might be an ethnic or specialty food market. Look for fruit that's firm, heavy for its size and unblemished, instructs the "Companion." Store at room temperature until ripe, then refrigerate "well wrapped" for up to a week. Pulp packed in syrup can also be found at ethic markets, the "Companion" says.
What does soursop taste like? The "Companion" says it has a "tropical fruit flavor." Waverly Root in his classic compendium, "Food" described it as having, "depending on who you read, (a) 'a biting wild taste,' (b) a taste which 'much resembles that of the black currant,' (c) 'a flavor of perfumed cream,' or which (d) unripe, 'tastes like turnips.' "
Do you have a question about food or drink? E-mail Bill Daley at: firstname.lastname@example.org. Snail mail inquiries should be sent to: Bill Daley, Chicago Tribune, 435 N. Michigan Ave., Chicago 60611. Twitter @billdaley.