Phosphate is one of the natural ingredients of almost all foods and is widely used in food processing as an important food ingredient and functional additive. The naturally occurring phosphate is phosphate rock (containing calcium phosphate). Sulfuric acid reacts with the phosphate rock to produce calcium dihydrogen phosphate and calcium sulfate that can be absorbed by plants to produce phosphate. Phosphates can be divided into orthophosphates and polycondensed phosphates: the phosphates used in food processing are usually sodium, calcium, potassium, and iron and zinc salts as nutrient fortifiers. Commonly used food-grade phosphates There are more than 30 varieties. Sodium phosphate is the main consumption type of domestic food phosphate. With the development of food processing technology, the consumption of potassium phosphate is also increasing year by year.