Carboxymethyl Cellulose (CMC) is a water-soluble cellulose ether obtained by chemical modification of natural cellulose. Due to the poor water solubility of carboxymethyl cellulose acid structure, in order to better apply it, its products are generally made of sodium salt, the molecular formula is [C6H7O2(OH)2OCH2COONa]n

Functional properties used in food:

Thickening and emulsifying stabilization

The consumption of sodium carboxymethyl cellulose can play an emulsifying and stabilizing role in the beverage containing oily lipoprotein, and the general fat beverage is characterized by containing different degrees of fat and a certain amount of protein, which is easy to separate and float when stored, forming an unattractive "collar", affecting the appearance of the product. 

In addition, protein is easy to condense and separate, especially for products with low pH value, protein is bound to condense, and CMC-Na can effectively solve these problems, which is dissolved in water into a transparent stable colloid, which can stabilize protein, while reducing the surface tension between fat and water, so that fat is fully emulsified. Therefore, CMC-Na is often used as a thickener in the food industry. 

Water retention

Sodium carboxymethyl cellulose has a hydration effect, in meat products, bread, steamed bread and other foods, can play a role in tissue improvement, and can make water less volatile, can improve product yield, increase taste. 

gelation

Thixotropic sodium carboxymethyl cellulose refers to large molecular chains that have a certain number of interactions and tend to form three-dimensional structures. After the three-dimensional structure is formed, the apparent viscosity of the solution increases. After breaking the three-dimensional structure, the apparent viscosity decreases. Thixotropy is a time-dependent change in apparent viscosity. The thixotropic carboxymethyl cellulose plays an important role in the gel system and can be used to make jellies and jams. 

Film-forming property

Sodium carboxymethyl cellulose can form a film on the surface of food, which can play a certain protective role for fruits and vegetables. Due to the existence of the film, a low oxygen and high carbon dioxide gas environment is formed between the film and fruits and vegetables, which reduces the exchange rate of gas and the exchange rate of matter, and is used to extend the shelf life of fruits and vegetables. 

Sodium carboxymethyl cellulose also has some other properties, such as suspension and chemical stability, which also laid the foundation for its wide application in the food industry.