If you’re vegetarian or just a little queasy about using gelatin, try agar (also known as agar-agar) instead. Called kanten in Japan, it’s made from seaweed and used in Asian cooking to make jelled desserts. It’s mostly fiber, with minimal calories, and like other sea vegetable products, it’s rich in trace minerals.
Agar sets and melts at a higher temperature than gelatin. While gelatin begins to melt at at 99F, agar doesn’t start melting until 185F. Yet once it has set, an agar-based dessert will be firmer than a gelatin-based dessert at room temperature.
Gelatin literally has a melt-in-the-mouth quality, while agar remains firm as you eat it. For something slightly closer to a soft gelatin dessert, try adding a thickener like tapioca flour, kuzu, or arrowroot to an agar-based recipe to give it a creamier texture.
Agar-agar comes in a variety of forms: squares, strips, flakes, and powder. The larger forms of agar take longer to dissolve, and the amount used varies. Powder is more powerful than flakes but trickier to measure, and it dissolves more easily. Consult the package directions and make any necessary adjustments to your recipe.
I use Eden Agar Agar Flakes, which is all I’ve seen in the natural grocery stores where I’ve shopped. I should see what I can find in Asian grocery stores, where I’ve heard it’s less expensive. The Eden flakes work fine, but do take a while to dissolve in the hot liquid. I’ve taken to blending the liquid after about five minutes of simmering to break up any remaining flakes, then returning the mixture to the stovetop briefly.
Though agar needs no refrigeration to gel, I’ve had better results gelling agar-based desserts in the refrigerator, where they set more quickly and firmly. I usually prefer the dessert cold anyway.
Agar’s filling qualities have made it the basis of the kanten diet in Japan. A low-cal, agar-based snack is eaten before each meal to cut appetite. At least one study in a reputable journal supports this diet for weight loss and lowering cholesterol. It makes sense that this might work, since adding fiber-rich foods to your diet to feel full is common wisdom for weight loss or weight maintenance.