超高压处理对牛乳微观特性影响的研究

Research on microcosmic characteristic of milk by ultra-high pressure treatment

采用DMBR-400数码显微镜和JSM-6360LV扫描电镜分别对超高压杀菌乳中的脂肪球和酪蛋白胶束的直径进行测定,并且与原乳、巴氏杀菌乳、超高温瞬时杀菌乳进行比较。结果表明:经过超高压杀菌处理过的牛乳酪蛋白胶束发生裂解,直径减小,脂肪球直径虽略有增大,但脂肪球膜没有被破坏,延缓了奶油的形成;而巴氏杀菌乳中酪蛋白胶束和脂肪球直径都略有增大,但脂肪球膜遭到破坏,而且发生聚集,加速了奶油的形成;超高温瞬时杀菌乳的酪蛋白胶束结构疏松,胶束直径明显增大,并且均质使得脂肪球直径减小,高温处理使得冷球蛋白变性,延缓了奶油的形成。

The diameter of fat ball and casein micelles in Ultra high pressure sterilized milk is measured by both Numeral microscope（DMBR-400） and Scan electron microscopy（JSM-6360LV） respectively, and is contrast with original milk, pasteurism milk as well as ultra high temperature sterilized milk. The results indicate： Casein micelles which was treated by Ultra high pressure are ripped and the diameter was diminished,through fat ball dimeter is augmented appreciably, while fat ball membrane is not destroyed, thus the cream forming time was suspend; The diameter of casein micelles and fat ball in pasteurism milk is augmented appreciably, but fat ball membrane is destroyed and the cream is formed accelerately; The casein micelles structure of ultra high temperature sterilized milk is loosen and casein micelles diameter is augmented distinctly,as well as homogenization can dimished the fat ball diameter and high temperature treatment can denaturalized the protein, thus can suspend the cream forming time.