Starch, which is made of corn, beans, sweet potatoes and potatoes, is white and shiny. It is used for sizing, pasting and thickening dishes, and is suitable for frying, frying, burning and soup paste dishes. It also has the function of heat preservation and freshness preservation. Common starch can be divided into dry starch and wet starch. Wet starch refers to the direct supply without dehydration and drying after processing. In the catering industry, dry starch mixed with water is also called wet starch.