Phosphate is one of the natural ingredients of almost all foods. As an important food ingredient and functional additive, it is widely used in food processing.
The natural phosphate is phosphate rock (containing calcium phosphate), which can be prepared by reacting sulfuric acid with phosphate rock to produce calcium dihydrogen phosphate and calcium sulfate which can be absorbed by plants. Phosphate can be divided into orthophosphate and condensed phosphate: the phosphate used in food processing is usually sodium salt, calcium salt, potassium salt, iron salt and zinc salt as nutritional fortifiers. There are more than 30 kinds of commonly used food-grade phosphate, and sodium phosphate is the main consumption type of food phosphate in China. With the development of food processing technology, the consumption of potassium phosphate is also increasing year by year.