Common examples of foods that contain gelatin are gelatin desserts, jelly, trifles, aspic, marshmallows, and confectioneries such as Peeps and gummy bears. Gelatin may be used as a stabilizer, thickener, or texturizer in foods such as ice cream, jams, yogurt, cream cheese, and margarine; it is used, as well, in fat-reduced foods to simulate the mouth feel of fat and to create volume without adding calories.
Gelatin is used for the clarification of juices, such as apple juice, and of vinegar. Isinglass, from the swim bladders of fish, is still in use as a fining agent for wine and beer.  Beside hartshorn jelly, from deer antlers (hence the name "hartshorn"), isinglass was one of the oldest sources of gelatin.
at 1:02 PM on Jun. 18, 2008