Functional properties of food

Starch

• thickens a liquid by forming a suspension such as a sauce
• forms a gel when the suspension is heated, like adding cornflour to a custard powder and milk mix

Sugar

• flavours by sweetening
• colours by caramelising when heated
• aerates when beaten with a fat such as in a cake mix

Proteins

• can coagulate which is when a liquid becomes firmer, for example when an egg is heated
• can aerate a mixture, like whisking egg whites in a meringue mix

Fats

• …