解冻方式对牦牛乳品质的影响  

Effect of thawing method on the quality of yak milk

作　　者：秦楠[1] QIN Nan(Humanities College,Xuchang Vocational Technology College,Xuchang 461000)

机构地区：[1]许昌职业技术学院人文学院,许昌461000

出　　处：《中国食品添加剂》2023年第1期180-186,共7页China Food Additives

基　　金：许昌市科技局2022年度许昌市软科学研究(20220314063)。

摘　　要：牦牛乳营养丰富,由于泌乳期较短人们常用冻藏的方式贮存,但是不同解冻方式对牦牛乳的品质有一定的影响。本研究观察不同解冻方式(4℃冷藏解冻、室温静水解冻、40℃水浴解冻、微波解冻)下-20℃和-40℃冻藏乳的品质差异。结果显示,静水解冻的冻结乳pH较低,菌落总数最多,在微生物的作用下营养成分含量也最低;冷藏解冻的冻结乳脂肪聚集程度最明显,稳定性最差;由于微波温度较高,使得微波解冻下牦牛乳的脂肪氧化度和蛋白水解度较高,营养成分含量偏低。相比较而言,40℃水浴解冻后乳的稳定性较高,解冻时间快,营养成分损失较少。此外,-40℃冻藏乳的蛋白和脂肪含量显著大于-20℃冻藏乳,提示冻结速率越快解冻时对乳品质的影响越小。Yak milk is rich in nutrients and often has to be stored by freezing due to its short lactation period,but different thawing methods have certain effects on the quality of yak milk. The quality of frozen milk at-20 and-40℃was investigated under different thawing methods(4℃ refrigerated thawing,room temperature hydrostatic thawing,40℃ water bath thawing and microwave thawing). The results showed that the frozen milk thawed in still water had lower pH values and the highest number of colonies,and nutrient content was the lowest due to microbe influence.The frozen milk thawed in refrigeration had the most significant fat aggregation and the least stability. The frozen milk thawed by microwave,due to the higher microwave temperature,both fat oxidation and protein hydrolysis of yak milk were higher,the nutrient content was lower. In comparison,the frozen milk thawed in water bath had higher stability and less loss of nutrients,the frozen milk was more stable and its thawing was faster. In addition,protein and fat content of frozen milk thawed in water bath at-40℃ was significantly higher than that of frozen milk at-20℃,it hinted that the faster the freezing rate,the lower the impact on milk quality during thawing.

关 键 词：牦牛乳 冷藏解冻 静水解冻 水浴解冻 微波解冻 品质 

分 类 号：TS252.1[轻工技术与工程—农产品加工及贮藏工程]