Generally speaking, the substitution degree of food grade and toothpaste grade carboxymethyl cellulose CMC is 0.70 to 1.00. As we all know, the good quality of the carboxymethyl cellulose CMC product with good replacement uniformity is reflected in the good appearance of the product and the high transparency of the aqueous solution. Then the replacement uniformity is good in the application, and the milk texture is shown in the application of dairy products. Delicate, good flavor and taste, long shelf life, etc.
Carboxymethyl cellulose CMC is a molecular compound. The degree of polymerization determines the molecular weight, and the most intuitive manifestation of physical properties is viscosity. Whether the molecular weight distribution of the product is uniform or not is reflected in the stability of the final product, the rheology of the solution, and the film-forming properties in the application. The molecular weight of carboxymethyl cellulose CMC is closely related to many physical properties of CMC, especially the rheology of CMC solution. By studying the molecular weight distribution of CMC and its solution characteristics, the setting of the production process, and the rheological characteristics and stability requirements in the application become more controllable.
For carboxymethyl cellulose CMC with the same average molecular weight, the one with a wide molecular weight distribution, that is, the greater the degree of molecular weight dispersion, has better fluidity than the one with a narrow distribution. Under the action of shearing force, the molecular chain is easily oriented. Using this feature, for CMC that requires pseudoplasticity, directional control can be achieved. It should be particularly pointed out that when the substituents are unevenly distributed on the macromolecular chain, although they can show obvious thixotropy, molecular chain scission may occur, which makes the stability of carboxymethyl cellulose CMC under certain conditions. Reduced.
For food such as liquid dairy products and fruit juice drinks, carboxymethyl cellulose in food is mainly used as a thickener and stabilizer. When CMC is used as a thickener, it is mainly considered that the higher the viscosity, the more economical it is. However, in yogurt and fruit juice, CMC with high viscosity is easily degraded due to poor acid resistance, but too much addition will also affect the taste. The study found:
1. The stability of carboxymethyl cellulose CMC is positively correlated with the uniformity of substitution. The better the uniformity of substitution, the better the stability of CMC; improving the process and appropriately increasing the degree of substitution can improve the uniformity of CMC substitution.
2. The stability of carboxymethyl cellulose CMC is negatively correlated with viscosity. The lower the viscosity, the better the stability of CMC. Therefore, low-viscosity CMC is often used in food stabilizers.