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Acidic milk drink nutrient-rich flavor aroma and much to the majority of consumers. Difficult to control product quality in the production process, prone to the phenomenon of flocculent, stratification, precipitation, serious impact on consumer acceptance of such products. To improve the stability of the product, the key problem to be solved Casein stability under acidic conditions. And this is often achieved by adding a stabilizer to. The current study the role of the stabilizer on the stability of acidic milk beverages, the method comprising: measuring the beverage system viscosity, amount of precipitation, the creaming rate indicators. However, these methods often destroy the structure of the acidic milk beverages during the measurement, and therefore has certain limitations. In this paper, a laser particle size analyzer, nuclear magnetic resonance spectrometer, Zeta potential and other instruments measured to add stabilizer of the particle size distribution of the product, the fluidity of the water molecules and the Zeta potential indicators of change, from a microscopic point stabilizer stabilizing effect of the acidic milk drink. Explore the mechanism of action of the stabilizers with casein, expanding the field of study of the stability of acidic milk drink, and laid the foundation for a better solution to the problem of unstable quality. Selected pectin, carboxymethyl cellulose sodium (CMC), melon child bean gum, xanthan gum, locust bean gum, water-soluble soybean polysaccharide, propylene glycol alginate (PGA), 7 kinds of stabilizers, and precipitated by centrifugation measured by the method for the stability of the acidic milk beverages. Screened out four kinds of stabilizers, respectively, pectin, carboxymethyl cellulose sodium (CMC), soybean water-soluble polysaccharides, alginic acid propylene glycol ester (PGA), systematically explored the precipitation rate of them in an amount of the product, viscosity particle size distribution, the fluidity of the water molecules and the Zeta potential. The stabilizing effect of the acidic milk drink. The results show that: the physicochemical properties change add stabilizers may be of the acidic milk drink. Stabilizer on the stability of the acidic milk beverages reduces the precipitation rate of the product, the viscosity increases, performance on the microscopic properties so that the particle size of the product is reduced, the flow of water reduced, the absolute value of the zeta potential is increased performance in the macro . Which pectin products Zeta potential impact the CMC principal effects of the product water flow, water-soluble soybean polysaccharides on the particle size distribution of the products have a greater impact on the fluidity of the water molecules and the particle size distribution of the PGA of products have a more significantly affected. Pectin, CMC, water-soluble soybean polysaccharide and PGA acidic milk beverages have a good stabilizing effect. However, when the amount of stabilizer is from 0.05% to occur the bridging flocculation phenomenon, so that the beverage system instability. With the increase in the amount of the stabilizer, the stability of the product is increased. The amount of stabilizer added were 0.40% pectin, the CMC 0.40% soybean water-soluble polysaccharide 0.40%, the PGA 0.30% basic stability of acidic milk beverages. Acidic milk beverage processing, process parameters can affect the stability of acidic milk drink. Pectin and CMC, for example, when its addition amount of 0.40% by measuring the the product precipitation rate and the particle size distribution changes studied the homogenizing pressure, the homogenization temperature, the temperature of the acidified, pH of the sterilizing temperature and sterilization time the influence of process parameters on the stability of acidic milk drink. The results show that: the homogenizing pressure of the product is 20 to 30 MPa, the homogenization temperature is 60 ℃, the precipitation rate of the product is low, and smaller particle size. Adjusted during the acid should be in the lower temperature, the pH of product precipitation rate and the particle size has little effect, but generally speaking the higher pH, the precipitation rate of the product is low, smaller particle size. Sterilization process the precipitation rate of the product sterilization temperature and sterilization time will have an impact, to be seen by the test results of the length of the sterilizing time than the sterilization temperature of the product precipitation rate is greater and therefore recommends the use of high temperature short time sterilization method.
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