不同地区牦牛乳营养成分比较研究

Comparative Analysis of Nutrient Components of Yak Milk from Different Regions

[目的]比较不同地区牦牛乳营养成分,为牦牛乳的进一步开发利用提供理论基础。[方法]对采自甘肃天祝、甘南玛曲和青海天峻3个地区,以及甘肃天祝3个牧区共150头份牦牛乳进行常规营养成分分析,包括检测乳蛋白,乳脂肪,全脂固体,非乳脂固体和乳糖含量,以及乳密度,冰点和酸度的测定。[结果]3个地区的牦牛乳脂肪含量和乳蛋白含量均存在显著差异,随着牦牛所处地区海拔的升高,其乳蛋白和乳脂肪含量呈现明显上升的趋势;而全脂固体、非乳脂固体、乳糖、冰点、密度和酸度的变化无明显规律。3个牧区的牦牛乳蛋白,乳脂肪以及全脂固体含量差异不显著,其非乳脂固体、乳糖、冰点和密度呈现不规律变化。[结论]海拔高度对牦牛乳的乳蛋白含量以及乳脂肪含量有一定的影响,海拔越高,其乳蛋白和乳脂肪含量越高。

[Objective] To analyze the nutrient components of yak milk from different regions and provide a theoretical basis for further development and utilization of yak milk.[Method] A total of 150 yak milk samples were collected from Tianzhu County,Maqu County and Tianjun County,and 90 yak milk samples were collected from three different yak farms in Tianzhu County.The milk protein content,milk fat content,fat solid content,non-fat solid content and lactose content,as well as the density,freezing point and acidity were determined,respectively.[Result] The milk protein content and milk fat content had significant differences between three regions.With the altitude increasing,the milk protein and milk fat were increased,but the fat solid content,non-fat solid content,lactose content,density,freezing point and acidity had no obviously regular change.The milk protein content and milk fat content had no significant difference between three yak farms in Tianzhu County.[Conclusion] The altitude may affect the milk protein content and milk fat content of yak milk.