Carrageenan

Carrageenan is extracted from Irish moss and other species of red algae. This stabilizer gets its name from where it was originally harvested, a small town in Ireland known as Carragheen. Nowadays it is mostly harvested in the Philippines and South America.

There are three commonly used types of carrageenan: kappa, iota, and lambda. A kappaiota carrageenan mix is frequently used in low-fat frozen desserts for its high gelling capacity. Each one alone forms a crumbly gel; together they are softer. Lambda carrageenan is preferred in regular-fat frozen desserts, where the fat content helps to stabilize the product without gelling. What this means is that lambda is a weaker gelling agent than kappa and iota. The amount of carrageenan used in a recipe varies from .01 percent to .04 percent of the total weight of the formula, depending on the type of frozen dessert.