牦牛乳蛋白多态性对奶酪凝乳特性的影响  

Effects of Yak Milk Protein Polymorphism on Cheese Coagulation Characteristics

作　　者：谈婷 罗毅皓[1] 孙万成[1] 孙祥祥 TAN Ting;LUO Yihao;SUN Wancheng;SUN Xiangxiang(College of Agriculture and Animal Husbandry,Qinghai University,Xining 810016,China)

机构地区：[1]青海大学农牧学院,青海西宁810016

出　　处：《食品与生物技术学报》2024年第6期40-49,共10页Journal of Food Science and Biotechnology

基　　金：国家自然科学基金项目(22167020)。

摘　　要：为了检测青海部分地区7家不同牧场牦牛乳κ-酪蛋白和αs1-酪蛋白基因多态性,作者分析了基因多态性对奶酪凝乳特性的影响。通过提取牦牛乳体细胞,采用限制性片段长度多态性聚合酶链式反应(polymerase chain reaction-restrition fragment length polymophism,PCR-RFLP)分析技术,对提取的DNA进行PCR扩增及酶切,对电泳条带进行基因分型;提取牦牛乳蛋白,采用高效液相色谱法(high performance liquid chromatography,HPLC)分析各样品与标准品色谱图,对出峰时间和出峰形状进行基因分型。利用流变仪测定不同基因型牦牛乳凝乳过程中流变特性,记录奶酪凝乳时间,计算奶酪得率。牦牛乳κ-酪蛋白基因有AA型、AB型和BB型3种基因型,3种基因型与凝乳特性的分析表明,在凝乳时间方面A等位基因为有利等位基因。牦牛乳αs1-酪蛋白存在AA型、AB型和BB型3种类型,3种基因型与凝乳特性的分析表明,在凝乳时间、奶酪得率、最大动力黏度和最大剪切速率方面B等位基因为有利等位基因。以上结果表明,青海7家牧场牦牛乳κ-酪蛋白和αs1-酪蛋白均存在基因多态性,κ-酪蛋白A等位基因和αs1-酪蛋白B等位基因是影响牦牛乳凝乳特性的主效基因。In order to detect the polymorphisms ofκ-casein andαs1-casein gene in yak milk from seven different pastures in certain areas of Qinghai province,the effect of gene polymorphisms on cheese coagulation characteristics was analized.Yak milk somatic cells were extracted,and polymerase chain reaction-restriction fragment length polymorphism(PCR-RFLP)analysis technique was used to extract DNA for PCR amplification and enzymatic digestion,followed by gene typing based on electrophoresis bands.Yak milk proteins were also extracted and high-performance liquid chromatography(HPLC)was used to analyze the chromatographic profiles of various samples compared to the standard samples,with a focus on peak time and peak shape for gene typing.The rheological characteristics during coagulation for different genotypes of yak milk were determined by rheometer.Cheese coagulation time was recorded,and cheese yield was calculated.The results showed that there were three genotypes for theκ-casein gene in yak milk,i.e.,type AA,AB and BB.The analysis of the three genotypes and coagulation characteristics showed that the A allele was favorable in terms of coagulation time.Similarly,for theαs1-casein gene in yak milk,three genotypes(AA,AB,and BB)were also identified.The analysis of the coagulation time,cheese yield,maximum dynamic viscosity,and maximum shear rate revealed that the B allele was favorable.The above results suggest that bothκ-casein andαs1-casein of yak milk in seven Qinghai farms have gene polymorphisms.The A allele inκ-casein and B allele inαs1-casein are the main effective genes affecting the coagulation characteristics of yak milk.

关 键 词：牦牛乳 蛋白质多态性 高效液相色谱法 限制性片段长度多态性聚合酶链式反应 凝乳特性 

分 类 号：S823.85[农业科学—畜牧学] Q78[农业科学—畜牧兽医]