Phosphates can be classified into orthophosphates and polyphosphates, and there are over thirty commonly used food-grade phosphate varieties. In food processing, commonly used phosphates include sodium salts, calcium salts, potassium salts, as well as iron and zinc salts as nutritional enhancers. Sodium phosphate salts are the main consumer type of food phosphates in China. Still, with the development of food processing technology, the consumption of potassium phosphate salts is also increasing year by year.

Phosphates are produced through a variety of methods tailored to the specific type and intended application. Mineral extraction, a common practice, involves mining, crushing, and processing phosphate rock or apatite to isolate phosphate-rich minerals. The wet process, utilizing sulphuric acid, reacts with phosphate rock to the acid to generate phosphoric acid and calcium sulfate, which is further neutralized with a base to yield phosphate salts. The thermal process heats phosphate rock with other minerals in an electric furnace, reducing it to elemental phosphorus that is oxidized into phosphoric acid and subsequently neutralized for phosphate salts. Synthetic production methods involve chemical reactions, such as combining phosphoric acid with metal compounds, to synthesize phosphate salts. Finally, biological production, though less prevalent for commercial-scale applications, can utilize microorganisms' metabolic activities to generate phosphates.

Acidity Regulation: Phosphates can adjust the acidity of foods, making them taste more mild and pleasant. This also helps inhibit the growth of microorganisms, extending the shelf life of foods. Water Retention: Phosphates bind with water in foods, helping them retain moisture and preventing drying. This keeps foods fresh, soft, and maintains their overall quality. Texture Improvement: Phosphates can interact with proteins and carbohydrates in foods, modifying their texture and making them smoother, silkier, and more appealing. Quality Stabilization: Phosphates stabilize the quality of foods, preventing discoloration, off-flavors, and other quality issues. This ensures foods are more reliable and consistent. Nutritional Enhancement: Phosphates can be used as mineral nutrient enhancers, adding essential minerals like calcium and phosphorus to foods. Beverage Additives: Phosphates are commonly used in beverages to adjust acidity, enhance flavor, and provide a smoother texture. They are especially prevalent in soft drinks and fruit juices. Dairy Products: Phosphates improve the stability and texture of dairy products like milk, yogurt, and cheese, ensuring they remain fresh and appetizing. Baked Goods: Phosphates are used in baking to improve the texture and quality of dough, resulting in better-baked products with increased stability.

Although phosphates offer certain benefits to the human body, excessive intake can lead to an increase in calcium ions within the body, potentially triggering the formation of stones. Therefore, when consuming foods that contain phosphates, it is crucial to pay attention to moderation and consume them in appropriate quantities.