牛奶中A1和A2 β-酪蛋白的检测与分析

Detection and Analysis of A1 β-casein and A2 β-casein in Bovine Milk

本研究建立了牛奶中A1和A2β-酪蛋白含量的HPLC检测方法。利用6mol/L盐酸盐水溶液提取,流动相选择A:0.1%三氟乙酸乙腈溶液,B:0.1%三氟乙酸水溶液,A+B=41+59(V+V),流速0.5m L/min,反相色谱柱进行分离,紫外检测器214nm检测。采用本方法可以较好地分离牛奶中的A1和A2β-酪蛋白,分别在0.16～1.65mg/m L和0.34～3.35mg/m L浓度范围内呈良好的线性关系,精密度RSD分别小于6.8%和7.5%(n=6),回收率范围分别为98.7%～103.5%和99.3%～105.0%。结果表明,方法操作简单、重现性好、准确度高,可为牛奶中A1和A2β-酪蛋白的进一步研究和应用作技术参考。

In view of the domestic A2 UHT milk which appeared recently in the market, the author established the HPLC detection method of casein A1 β-casein and A2 β-casein content in milk. Extraction using 6 mol/L hydrochloride solution, the selection of mobile phase A：0.1% TFA acetonitrile solution, B：0.1% TFA aqueous solution and A＋B=41＋59（V＋V） and 0.5 m L/min flow rate and reversed-phase liquid chromatography column and 214 nm detection. The method can effectively isolate A1 β-casein and A2 β-casein, respectively in 0.16 mg/m L～1.65 mg/m L and 0.34 mg/m L～3.35 mg/m L concentration range showed a good linear relationship. The RSD of precision was less than 6.8% and 7.5%（n=6）, the range of recovery rate were 98.7%～103.5% and 99.3%～105%. The results show that the method is simple, reproducible and accurate. It can be used as a technical reference for further research and application of A1 β-casein and A2 β-casein in bovine milk.