Starches

Starch is a primary component of flour, left when the protein is separated from the rest of a grain or other plant. It is familiar to the cook as a fine white powder used for thickening sauces, fruit pies and puddings, and has the advantage of being shiny and translucent when cooked, with a light texture. Starch is a more effective thickener than flour; up to twice the volume of flour is required for the same effect.

Grains, notably corn, and roots or tubers such as arrowroot, potato and cassava are the two main sources of starch for thickenings. Cornstarch is used for sweet sauces, puddings and Asian dishes. Arrowroot is often used to thicken fruit glazes, savory brown sauces or dessert mixes. However, if arrowroot is cooked for too long, it loses its thickening property. Potato starch has similar uses. Tapioca (finely ground from the cassava root) and sago (extracted from an Indian palm) are also used as thickeners for sauces, puddings and fruit pies. Root starches have a slightly lighter thickening effect than grain starches.