Functions of Food Grade CMC

What is Carboxymethyl Cellulose?

Carboxymethyl cellulose (CMC), a white crystalline substance, is a water-soluble cellulose ether obtained by chemically modifying natural cellulose. Since the water solubility of carboxymethyl cellulose's acid form is not good, its products are generally made into sodium salts for better application. The physicochemical properties of carboxymethyl cellulose sodium, abbreviated as CMC-Na, are white to light yellow powder, granules, or fibrous substances, which are highly hygroscopic and easily soluble in water. In a neutral or alkaline state, the solution is highly viscous.

Functions of Food Grade CMC

Thickening and Emulsification Stabilization

Food grade CMC can play an emulsification stabilization role in beverages containing oil and protein. Generally, oily beverages feature various fat contents and a certain amount of protein, which tend to separate and float to the top when stored, forming unattractive "rings" that affect the product's appearance. Additionally, proteins are prone to aggregation and separation, especially in products with low pH values, where proteins inevitably coagulate. Food grade CMC can effectively solve these issues by dissolving in water to form a transparent stable colloid, stabilizing proteins, and reducing the surface tension between fat and water for thorough emulsification of the fat. Therefore, food grade CMC is often used as a thickening agent in the food industry.

Water Retention

Food grade CMC has hydrating properties and can play a role in improving texture in meat products, bread, and steamed buns. It also helps in preventing moisture loss, thereby increasing product yield and enhancing flavor.

Gelling Activity

Thixotropic carboxymethyl cellulose refers to a situation where the macromolecular chains have a certain amount of interaction, tending to form a three-dimensional structure. After the formation of the 3D structure, the apparent viscosity of the solution increases; once the 3D structure is broken, the apparent viscosity decreases. Thixotropy refers to changes in apparent viscosity depending on time. Thixotropic carboxymethyl cellulose is important for gel systems and can be used to make jelly and jam.

Film Formation

Food grade CMC can form a film on the surface of foods, providing a certain degree of protection for fruits and vegetables. The presence of the film creates a low-oxygen, high-carbon dioxide environment between the film and the produce, reducing the rate of gas and material exchange, and thereby extending the shelf life of fruits and vegetables.