By Harold McGee
Gelatin isn’t the only ingredient that cooks have at their disposal for turning a flavorful liquid into an intriguing solid. Starch gels give us various pie fillings and the candy called Turkish Delight, and pectin gels the many fruit jellies and jams. Along the seacoasts of the world, cooks found long ago that various seaweeds release a viscous substance into hot water that forms a gel when the water cools. These substances are not proteins like gelatin, but unusual carbohydrates with some unusual and useful properties. Food manufacturers use them to make gels and to stabilize emulsions (cream and ice cream, for example).