摘要
阐述了高体细胞牛乳化学成分及微生物的变化,论述了产生这些变化的原因以及这些变化对乳制品加工、贮藏和销售所带来的一系列不良影响。主要表现在高体细胞牛乳中脂肪氧化酶含量升高,引起游离脂肪酸含量上升,牛乳易产生酸败味;牛乳中蛋白水解酶以及血纤维蛋白溶酶含量增加,引起乳蛋白水解,造成干酪产量下降,凝固型酸乳凝乳不坚固,UHT灭菌乳保质期缩短等质量缺陷;牛乳中盐类比例失调,使牛乳热稳定性降低,凝固型酸奶的凝乳疏松且易碎裂,乳清易析出;乳中过氧化氢酶和过氧化物酶含量升高,使产品品质不稳定,风味欠佳;牛乳中有害微生物含量增加,降低产品的食用安全性;治疗乳房炎所用的抗生素残留阻碍乳酸菌的发酵过程。这些变化都可能对乳制品的生产造成巨大损失。
Abnormal chemical composition and microorganism in the high somatic cell count (HSCC) milk cause a serial adverse influence on the milk processing,storing and selling.The first,more lipoxidase in HSCC milk increase the ratio of the free fatty acid,which causes rancid aroma in the dairy products.The second,more proteolytic enzyme and plasminogen in HSCC milk cause more proteolysis,which decreases the output of the cheese and softens the cured tension of the yoghurt.The third,the disordered proportion of the salt decreases the heat stability of the milk.The fourth,more pathogenic germs decrease the safety of the dairy products.The last,due to much more antibiotic being used to cure mastitis,the residue of them in the milk may hamper the fermentation of the lactic acid bacteria.
出处
《中国乳品工业》
CAS
北大核心
2003年第5期38-41,共4页
China Dairy Industry
