There are several advantages to using agar agar over gelatin. For one thing, it is suitable for vegans and vegetarians because it is free of animal protein. In addition, unlike gelatin, which requires a few hours of refrigeration, agar will usually set at room temperature in about 60 minutes. Agar also has a higher melting point than gelatin, which means it retains a chewy bite in the mouth and its shape and texture when served on a hot day.
However, although both gelatin and agar require a brief soak in cold water, agar must be boiled for 5 minutes to thoroughly dissolve its carbohydrates. Like gelatin, though, agar will not set with certain fruit enzymes unless the fruit is first cooked. Fruits that contain enzymes that inhibit gelling ability include raw pineapple, mango, kiwi, peaches, mango and fig.
Agar comes in three forms – solid bar, flaked and powdered. The powdered form is the easiest to use and dissolves faster. You can also use it in the same ratio as gelatin. In other words, 1 teaspoon of agar is the equivalent of 1 teaspoon of gelatin.
Use agar to thicken jellies, custards, puddings, sauces, soups and other foods; as a substitute for egg whites (1 tablespoon agar mixed in a tablespoon of water equals one egg); to make molded candies flavored with juice or chocolate milk and; to make simple syrups for your favorite cocktails.
The gelling properties of agar were first discovered in 1658 by a Japanese
innkeeper upon discarding the remains of a pot of seaweed soup on a frigid
winter’s night. This is why agar is known in Japan as kanten, which means “cold
weather.” The name “aga-agar” means “read algae” in Malay, although the plant is
also known Jaffna moss, Ceylon moss and Japanese isinglass throughout Asia,
Malaysia and Indonesia.