Q. I am a vegetarian and would like to find a substitute for gelatin. Can I use agar? The stuff I found in the Asian market looks like it would need to be ground up.
Agar, also called agar-agar, is a gelatinous seaweed derivative, and it's very versatile. Agar is used as a laxative, a diet food, a clarifying agent, a medium for bacterial cultures and – yes – a vegetarian gelatin substitute.
Agar is naturally off-white or ivory in color, but once it's dissolved, it sets as a transparent gel. It has slightly stronger gelling powers than gelatin, and products made with it are usually firmer. Solutions made with agar will solidify at room temperature, but should be refrigerated because of the high protein content, which makes it a breeding ground for microorganisms.
Food-grade agar is sold in a number of forms, the most common of which is probably powdered. This agar should be available at supermarkets, and can be substituted measure for measure for gelatin. Powdered agar is usually chemically treated to ensure a white color and neutral flavor. You also can find it as dried flakes and strips at Asian markets. These less-processed forms are still neutral in flavor. One tablespoon of flakes is the equivalent of a teaspoon of gelatin. Flakes and strips can be found at New Century Grocery & Food, 4500 N. Tryon St.
Either type will work for most uses, and only those seeking authenticity or with an aversion to food additives need seek out the flaked agar.
Agar has some drawbacks that are common to most gelling agents – it cannot set liquids made with fresh papaya, pineapple or kiwi because of protein-breaking enzymes that occur naturally in those fruits. It also cannot produce a gel in highly acidic liquids – the acids break down the proteins and inhibit gelling action.