After putting grain material into inflating machine, With heating, pressure, material moisture is overheating. When material become soft. When reaching a certain high pressure and open the lid of the extrusion equipment, high pressure quickly become normal pressure. The overheating mosture in raw material instantly vapor vapor and explode.  Water molecules can expand 2000 times. Huge expansion pressure not only destroyed the external form of raw materials, but also pull off the internal molecular structure of materials, the insoluble long chain starch chopped into water-soluble short chains starch, dextrin and sugar. Therefore, reduces the insoluble substance in the puffed food, water-soluble substances increased.

According to the different way of puffing, puffed foodcan be divided into : 1) the Fried puffed food, like potato chips, Fried potato chips, etc.2) baked puffed food, such as prosperous snow cake, want want fairy bay, etc.3) extrusion food, such as wheat circle, shrimp, etc.4) pressure puffed food, wait like popcorn.5) other categories.