Food Additives—Sodium Carboxyme Thyl Cellulose
Sodium carboxymethyl cellulose (CMC) is a carboxymethylated derivative of cellulose, also known as cellulose gum, and is the most important ionic cellulose gum.
CMC is usually an anionic polymer prepared by the reaction of natural cellulose with caustic soda and monochloroacetic acid, and the molecular weight of the compound ranges from several thousand to millions. CMC is a natural cellulose modification, and the Food and Agriculture Organization of the United Nations (FAO) and the World Health Organization (WHO) have officially called it "modified cellulose". The synthesis method of sodium carboxymethyl cellulose was invented by the German E.Jansen in 1918, and was patented in 1921, and since then it has been commercially produced in Europe.
CMC was only used as a colloid and binder for crude products. 1936-1941, carboxymethyl cellulose sodium industrial application research is quite active, published several quite enlightening patents, during the Second World War, Germany used CMC as an anti-redeposition agent in synthetic detergent, and as a substitute for some natural gums (such as gelatin, gum Arabic), so that the CMC industry has been greatly developed.
The American Hercules company began the industrial production of CMC in 1943 and produced refined sodium carboxymethyl cellulose products in 1946, which were recognized as safe food additives.
CMC has many special properties, such as thickening, bonding, film formation, water retention, emulsification, suspension, and itself non-toxic, odorless, not easy to fermentation, good thermal stability and other characteristics and is widely used in petroleum, geology, daily chemical, food, medicine and other industries, known as "industrial MSG".Solid CMC is stable to light and room temperature, and can be stored for a long time in a dry environment. CMC is a type of cellulose ether, usually in short lint (up to 98% cellulose) or wood .The compound is prepared by treatment with SODIUM HYDROXIDE and then reacted with CHLOROACETIC ACID sodium, with a molecular weight of 6400 (±1000). There are usually two preparation methods: Coal-water method and solvent method. Other plant fibers have also been used to prepare CMC.
Functions, Features, and Applications
CMC is not only a good emulsifying stabilizer and thickening agent in food application, but also has excellent freezing and melting stability, and can improve the flavor of products and prolong the storage time.
In 1974, the Food and Agriculture Organization of the United Nations (FAO) and the World Health Organization (WHO) approved the use of pure CMC in food after strict biological and toxicological studies and tests. The international standard safe intake (ADI) is 25mg/kg body weight/day.
1.Thickening and Emulsifying Stability
Ingestion of CMC may play an emulsifying and stabilizing role in beverages containing fat and protein. This is because CMC becomes a transparent stable colloid after being dissolved in water, and protein particles become particles with the same charge under the protection of colloid membrane, so that protein particles can be in a stable state. It also has a certain emulsifying effect, so at the same time can reduce the surface tension between fat and water, make fat fully emulsified.
CMC can improve the stability of the product due to the fact that the pH of the product deviates from the egg
2. Improve Bulkiness
CMC can be used in ice cream to improve the expansion degree of ice cream, improve the melting speed, give good shape and taste, and control the size and growth of ice crystals during transportation and storage.
This is because CMC has good water retention and dispersibility, and combines the protein particles, fat spheres and water molecules organically to form a uniform and stable system
3. Hydrophilicity and Rehydration
CMC is generally used in bread production, which can make honeycomb even, increase volume, reduce dregs, and keep heat preservation fresh. The noodles added with CMC had good water retention, good cooking resistance and good taste.
This is determined by the molecular structure of CMC, which is a derivative of with a large number of hydrophilic groups in the molecular chain: -OH group, -COONa group, so CMC has better hydrophilicity and water retention than cellulose.
4. Gelation
The thixotropic CMC refers to that macromolecular chains have a certain number of interactions and tend to form three-dimensional structures. After the formation of three-dimensional structures, the viscosity of the solution increases, and after the breaking of three-dimensional structures, the viscosity decreases. The thixotropic phenomenon is that the apparent viscosity changes depend on time. The thixotropy CMC plays an important role in the gelling system and can be used to make jelly, jam and other foods.
5. It can be used as a clarifying agent, foam stabilizer, to enhance the taste
CMC can be used in the production of wine, so that the taste is more mellow and rich, and the aftertaste is long; It can be used as a foam stabilizer in beer production to make the foam rich and lasting and improve the taste.
CMC is a kind of polyelectrolyte, which may be involved in various reactions to maintain the balance of wine and combine with the crystals that have been formed to change the structure of the crystals and change the existing conditions of the crystals in the wine, causing the agglomeration of precipitates.
Note: The article part from the network, the copyright belongs to the original author, if there is infringement, please contact to delete
