Food additives are synthetic or natural substances added to food to improve the quality of food such as color, aroma and taste, and to meet the needs of preservation and processing technology. The processing of food and the use of additives must conform to the Food Safety Law, and no chemical substances other than food additives can be produced from non-food raw materials. As one of the food additives, sodium tripolyphosphate is not added randomly in food.

Phosphorus is an essential element for human body, but the amount of sodium tripolyphosphate, sodium hexametaphosphate and sodium pyrophosphate used as food additives and intake are limited. In fact, food-grade phosphate is safer than many additives and can be safely used.

Food grade sodium tripolyphosphate is generally used as water retention agent, quality improver, PH regulator and metal chelating agent in food.

"Hygienic Standards for the Use of Food Additives" (GB2760-2011) of China stipulates that:

1. The maximum usage of sodium tripolyphosphate in canned, fruit juice (fruit flavor) and vegetable protein drinks is 1.0 g/kg.

2. Sodium tripolyphosphate is used in dairy products, poultry products, meat products, ice cream and instant noodles with a maximum usage of 5.0g/kg.

3. Sodium tripolyphosphate is used for the salting of raw ham meat, adding 3 mixed salts (91.65% refined salt, 8% sugar and 0.35% sodium nitrite) 2.2kg and 85g sodium tripolyphosphate per 100kg meat. It is well stirred and uniformly marinated for 48-72 hours in cold storage at 0-4°C.

4. When sodium tripolyphosphate is combined with sodium pyrophosphate and sodium phosphate, the phosphate meter shall not exceed 5g/kg.

5. Western-style cooking, smoked ham according to GB13101-1991 "Western-style cooking, smoked ham hygienic standards" implementation, compound use should not exceed 5g/kg (Western-style ham can be added appropriately, with phosphate as 8g/kg.

6. Food grade sodium tripolyphosphate can soften the skin of broad bean when used in canned bean production. Many fruits and vegetables have tough coats, which become more tough as they mature.

7. Adding sodium tripolyphosphate to the water for blanching or soaking fruits and vegetables can complex calcium, thus reducing the toughness of the skin.