冻藏条件对牦牛原料乳品质的影响  

Effect of freezing conditions on the quality of raw milk from yaks

作　　者：雷昌贵[1] 孟宇竹 陈锦屏[3] 蔡花真[1] 张晓东 LEI Changgui;MENG Yuzhu;CHEN Jinping;CAI Huazhen;ZHANG Xiaodong(Food and Chemical Engineering Department,Henan Quality Polytechnic,Pingdingshan 467000;Modern Service Department,Pingdingshan Institute of Technology,Pingdingshan 467000;College of Food Engineering and Nutritional Science,Shaanxi Normal University,Xi’an 710119)

机构地区：[1]河南质量工程职业学院食品与化工学院,平顶山467000 [2]平顶山技师学院现代服务系,平顶山467000 [3]陕西师范大学食品工程与营养科学学院,西安710119

出　　处：《中国食品添加剂》2023年第8期147-155,共9页China Food Additives

基　　金：全国食品产业职业教育教学指导委员会2022年度教育教学改革与研究课题(SHK2022024);全国食品产业职业教育教学指导委员会2022年度教育教学改革与研究课题(SHK2022068);河南省教育科学规划一般课题(2022YB0575)。

摘　　要：牦牛乳因其营养价值丰富、风味独特而逐渐受到消费者关注。然而,因牦牛的泌乳期短、产奶量偏低,在贮存保鲜等方面存在诸多问题。本研究将牦牛原料乳在不同冻藏条件贮存180 d,分别在30 d、90 d、180 d时测定其新鲜度、蛋白质特性、脂肪特性和感官评价等的变化,探究冻藏条件对牦牛乳在贮存期间品质的影响。结果显示,与新鲜原料乳比较,各组牦牛乳在冻藏30 d内的菌落总数及嗜冷菌数量显著下降(P<0.05);冻藏至90 d时,各组微生物数量有所增加,-20℃及-40℃组中牦牛乳的酸度、蛋白水解度、脂肪氧化度以及脂肪球的聚集程度和颗粒大小显著增加(P<0.05),而乳的热稳定性、可溶性蛋白含量显著下降(P<0.05),-80℃组只有蛋白含量发生显著变化;当原料乳冻藏至180 d时,各组乳的品质进一步降低,其中-40℃组的显著优于-20℃的冻藏组,电子舌分析结果也显示在-40℃冻藏条件下的牦牛乳中酸、涩及苦的味感值优于-20℃冻藏组,而-80℃组乳的品质则显著优于前两者。Yak milk is gaining attention from consumers because of its nutritional value and unique flavour.However,due to the short lactation period and low milk yield of yaks,there are many problems in storage and preservation.In this study,the freshness,protein properties,fat properties and sensory evaluation of raw yak milk were measured at 30 d,90 d and 180 d under different freezing conditions for 180 d.The effect of freezing conditions on the quality of yak milk during storage was investigated.The results showed that the total number of bacterial colonies and the number of cold-loving bacteria decreased significantly(P<0.05)during 30 d of freezing,while the number of microorganisms increased at 90 d.The acidity,protein hydrolysis,fat oxidation,fat globule aggregation and particle size of yak milk increased significantly(P<0.05)in the-20℃and-40℃groups.When the raw milk was frozen for 180 d,the quality of milk in each group decreased further,with the-40℃group being significantly better than the-20℃group,and the results of electronic tongue analysis also showed that the acidity,astringency and bitterness of yak milk in the-40℃group were better than those in the-20℃group.The-80℃group was significantly better than the-20℃group.

关 键 词：牦牛乳 冻藏 新鲜度 品质 感官评价 

分 类 号：TS252.26[轻工技术与工程—农产品加工及贮藏工程]