不同冷藏条件对牦牛乳品质的影响分析  

Analysis of the Influence of Different Refrigeration Conditions on the Quality of Yak Milk

作　　者：李菁 李翔 马玉俊 顾庆云[1] LI Jing;LI Xiang;MA Yujun;GU Qingyun(Xizang Vocational and Technical College,Lhasa Xizang 850000,China)

机构地区：[1]西藏职业技术学院,西藏拉萨850000

出　　处：《现代畜牧科技》2024年第4期7-9,共3页Modern Animal Husbandry Science & Technology

基　　金：西藏职业技术学院2022年度校级科研课题(2022YBKT-11)。

摘　　要：目的:分析不同冷藏条件对牦牛乳品质的影响。方法:选择西藏自治区某养殖场内的同一头健康哺乳期牦牛的原料乳作为试验对象,分别置于-20、-40、-80℃等3种不同温度进行冷藏,分析和探讨不同冷藏条件对牦牛乳品质的影响。结果:-80℃冷藏的牦牛乳p H值和热稳定性显著高于-20℃和-40℃冷藏(P<0.05),-80℃冷藏的牦牛乳菌落数显著低于-20℃和-40℃冷藏(P<0.05),且冷藏温度越低,乳pH值和热稳定性越高,乳中菌落数越少。-20、-40、-80℃冷藏的牦牛乳脂肪粒径分布宽度、蛋白水解度、可溶性蛋白含量、总蛋白含量、红—绿强度和亮度均差异显著(P<0.05)。-20、-40、-80℃冷藏的牦牛乳组织状态、滋味和色泽差异显著(P<0.05);冷藏温度越低对牦牛乳气味感官评价越好。结论:-80℃冷藏条件下的牦牛乳品质最佳,为今后延长牦牛乳货架期和乳制品加工提供参考依据。Objective:To analyze the effect of different refrigeration conditions on the quality of yak milk.Methods:The raw milk of the same healthy lactating yak in a farm in Xizang Autonomous Region was selected as the test object,and was refrigerated at three different temperatures,namely-20℃,-40℃,and-80℃.The effects of different refrigeration conditions on the quality of yak milk were analyzed and discussed.Results:The results showed that the pH and thermal stability of yak milk refrigerated at-80℃were significantly higher than those refrigerated at-20℃and-40℃(P<0.05),and the bacterial count of yak milk refrigerated at-80℃was significantly lower than those refrigerated at-20℃and-40℃(P<0.05).Moreover,the lower the refrigeration temperature,the higher the milk pH and thermal stability,and the lower the bacterial count in the milk.The distribution width of fat particle size,protein hydrolysis degree,soluble protein content,total protein content,red green intensity,and brightness of yak milk refrigerated at-20℃,-40℃,and-80℃showed significant differences(P<0.05);There were significant differences in the tissue status,taste,and color of yak milk stored at-20℃,-40℃,and-80℃(P<0.05);The lower the refrigeration temperature,the better the sensory evaluation of the odor of yak milk.Conclusion:The quality of yak milk under-80℃refrigeration conditions is the best,which provides a reference basis for extending the shelf life of yak milk and processing dairy products in the future.

关 键 词：冷藏 牦牛 乳 品质 温度 

分 类 号：S823.85[农业科学—畜牧学]