What are the classifications of citric acid？

• Citric acid can be divided into anhydrous citric acid, citric acid monohydrate and citric acid dihydrate (sodium citrate) according to its water content.

Citric acid monohydrate is used in most food and beverage industries as an acid, flavoring, preservative and fresh-keeping agent. Anhydrous citric acid is deliquescent in humid air because it does not contain any crystal water. It is also used as antioxidant, plasticizer and detergent in chemical industry, cosmetics industry and washing industry.

Anhydrous citric acid is also used in the food and beverage industry, but the most used sector is chemical medicine manufacturing, followed by paper making, aluminum smelting, tungsten smelting, rayon, rayon and soap manufacturing.

• Citric acid can be divided into food grade and industrial grade according to different uses.

In industry, citric acid as a detergent aid can improve the performance of washing products, make metal ions precipitate rapidly, and prevent pollutants from re-attaching to the fabric. It can also improve the performance of surfactants and is a good chelating agent, which can remove some harmful metals.

No matter which kind of citric acid is used in food, it must be food-grade. The packaging must be clearly marked with the words “food additive”, and industrial grade is not allowed. The scale inhibitor must also be food grade if it involves drinking water.