青海高原地区牦牛肉营养成分分析与品质评价

选取青海高原5个地区牦牛肉的3个不同部位，对其营养成分进行分析评价和比较，为青海高原牦牛肉再加工产品的开发和利用提供依据。采用SPSS 19.0分别对青海高原5个不同地区牦牛肉的相同部位之间和同一地区牦牛肉的不同部位之间各营养成分进行主成分分析和多重比较分析，同时对青海高原地区与外省份其他地区牦牛肉之间、牦牛肉与其他品种牛肉之间进行了比较，最后还对牦牛肉品质贡献大的指标性成分进行综合评价。指标性营养成分存在差异，但均具有高蛋白质、低脂肪、营养丰富等的特点。牦牛肉营养成分与当地海拔高度呈现正相关趋势与放牧饲养管理有关：高海拔地区的牦牛进食含有更多营养和能量的牧草获得的营养成分也更多。不同品种牛肉中营养成分除了受上述影响因素外，还与生活行为模式、进食饲喂情况、半野生放牧环境等因素有关。综合评价分别来自海西州天峻县龙门乡和海北州刚察县沙柳河镇的牦牛肉品质更佳，分析其原因是气候因素中的降水量是牧草生长的主导因素之一，从而间接影响了牦牛肉的品质。青海高原牦牛肉营养价值高，本研究可为其质量控制提供一定的参考。

Analysis of Nutritional Compositions and Quality Evaluation of Yak Meat from Qinghai Plateau Regions

Three different body parts of yak meat from five regions of Qinghai Plateau were selected to analyze, evaluate and compare the nutritional compositions, providing a basis for the development and utilization of yak meat reprocessed products in Qinghai Plateau. SPSS 19.0 was used to conduct the principal component analysis and multiple comparative analysis of nutritional compositions of yak meat from the same body parts in five different regions and the different body parts in the same region in Qinghai plateau, respectively. At the same time, the differences among yak meat in Qinghai plateau region and other provinces, and among yak meat and other varieties of beef were also compared. Finally, the indicative compositions greatly contributing to the yak meat quality were evaluated comprehensively. There were differences in indicative nutrients, but they all had the characteristics of ''high protein, low fat and rich nutrition''. The trend of positive correlation between the nutrients of yak meat and local altitude was related to grazing and feeding management. Yaks at high altitudes got more nutrients by eating grasses with more nutrients and energy. In addition to the above-mentioned factors, the nutritional compositions of different varieties of beef were also related to the life behavioral patterns, eating and feeding conditions, semi-wild grazing environment and other factors. After comprehensive evaluation, the quality of yak meat from Longmen township, Tianjun county, Haixi prefecture and Shaliuhe town, Gangcha County, Haibei Prefecture were better than that from other regions. The reason was that the precipitation of climatic factors was one of the main factors of herbage growth, which indirectly affected the quality of yak meat. This study could provide a basis for quality control of yak meat in Qinghai Plateau with high nutritional value.