不同牛场泌乳早期奶牛春季和夏季牛奶氨基酸含量的比较分析

摘要

The objective of this study was to assess raw milk amino acids composition in different farms between the spring and summer to provide a basis for improving the qualitiy of milk. Milk samples were collected from 6 cities (Beijing, Anhui, Heilongjiang, Neimeng, Xinjiang and Xi'an) in the spring and summer, respectively. Amino acids were extracted by hydro-lyzed with HC1, and concentrations of amino acids were determined by Hitachi L-8900 high speed amino acid analyzer. The experimental datas were analyzed by SAS 8. 0 with GLM procedure. The results showed that significant variation of Cys, Val, Tyr and Phe were determined between the spring and summer (P<0. 01) , while others were not siginificant differences (P> 0. 05). Significant difference of all amino acids existed among these six regions (P<0. 01). The interaction effect between seasons and locality were highly significant on the amino acids concentrations of whole milk (P<0. 01). It was concluded that amino acids in raw milk were influenced by locality significantly, while Cys, Val, Tyr and Phe were also affected by seasons.%比较研究不同奶牛场、不同季节牛奶中氨基酸组成及含量的差异,探讨牛奶中氨基酸含量受其影响的变化规律,为改善乳品质提供一定的理论依据.采集北京、滁州、哈尔滨、呼和浩特、乌鲁木齐和西安6个地区奶牛场春季和夏季的奶样,经盐酸水解后采用日立L-8900型氨基酸自动分析仪测定其中17种氨基酸,试验数据通过SAS 8.0统计分析.结果显示,不同季节牛奶中的缬氨酸、酪氨酸、苯丙氨酸和半胱氨酸含量差异极显著(P＜0.01),而其他13种氨基酸含量差异不显著(P＞0.05)；不同奶牛场牛奶氨基酸含量差异极显著(P＜0.01),不同奶牛场春季和夏季互作效应对牛奶中氨基酸各组分含量均有极显著的影响(P＜0.01).因此,不同奶牛场牛奶氨基酸组分及含量差异显著(P＜0.05),而季节因素对牛奶中缬氨酸、酪氨酸、苯丙氨酸和半胱氨酸含量影响较大.