Preparation Process Of Microencapsulation Of Milk Fat

Whey protein as wall material, the microencapsulation of fat is not only to prevent the oxidation of milk fat and the volatile of flavor, but also to become powdered milk fat that is easy storage, transportation and use, while making the fat and whey protein can be more widely used in food production.In this study, the microencapsulation of fat is made by vacuum freeze-drying. The factors of microcapsules fat such as the wall material and core material ratio, the wall material ratio, the solid concentration, stabilizer amount, homogenization pressure, emulsification temperature, drying time, conducts a systematic study and optimizes the formulation and the process parameters of microcapsules. The nature of the microcapsules were evaluated to explore the microcapsules in food applications, and get conclusions:First, the process conditions and measurement method for the preparation of microcapsules were optimized. Microencapsulation fat by measuring the embedding rate, evaluate the effect of microencapsulation and determine the optimum conditions:the core material/wall material ratio is 25%, the ratio of wall material is 1:2, solids concentration is 45%, monoglycerides dosage is 0.7%, homogenization pressure is 40MPa, emulsifying temperature is 60℃, pre-freezing temperature is-20℃, pre-freezing time is 8h, drying time isllh. Under this conditions, the embedding rate of microencapsulation fat gets to 88.73%. Optimizing the embedding rate for the calculation, extract total oil with ether:ethanol:petroleum ether= 2:2: 1, the time was 30min; extract surface oil with petroleum ether, the time was 5min.Then, the properties of milk fat microencapsulated powder comprise microcapsules of about 5μm particle size distribution and the microencapsulated powder’s water content was 2.7% after freeze-drying and the solubility was 92.8%. The fingerprint and odor tests by electronic nose showed that the flavor of release rate of the volatile components in fat microencapsulated was controlled better, extending flavor retention period. Through the storage and stability tests, the stability of microencapsulated fat is fine, and can be stored 160 days at room temperature.Finally, the microencapsulated fat products by freeze-dried was used into Chinese Sausage to make low-fat Chinese sausage; using the products into soy drinks produced nutrient drinks, and get a better recognition by sensory evaluation.