OFF THE SHELF
Agar-agar a gelatin for vegetarians

By Wanda A. Adams
Advertiser Food Editor

Agar-agar is widely used as a culturing medium in biology; most bacteria can't digest it, and it is stable at the warm temperatures suitable for growing microorganisms. A side note: It was a woman, Lina Hesse, a technician and illustrator working with her scientist husband in Germany, who gave Dr. Robert Koch the idea of using it in the lab in 1881. Her husband, Walther, noted that her jellies held up in hot weather and asked her about it, later mentioning her secret ingredient to Koch.

This product, whose name derives from a Malay word for jelly, comes in a variety of forms: powdered, flaked or cakes or strips like the one pictured here. You can substitute it equally for powdered gelatin in recipes. Flakes are less effective than powder; if a recipe calls for 1 teaspoon of powder, substitute 1 tablespoon of flakes. The rule of thumb for a firm jelly, says the Vegetarian Society of the United Kingdom, is 2 teaspoons of powder or 2 tablespoons of flakes for every 2 cups liquid. Some foods prevent jelling: kiwi, pineapple, figs, papaya, mango, peaches, chocolate and spinach.ÊIn general, acidic foods weaken jelling.

To use, soak kanten in liquid for 10-15 minutes; gently bring it to a boil, stirring; test by placing a small amount in a saucer. It should set in 20 to 30 seconds. Add agar-agar or liquid as needed.