检测牛乳中β-乳球蛋白含量可以判断牛乳热处理程度。本文利用UPLC检测速度快、灵敏度高的特点，选择210 nm检测波长进行检测，建立超高效液相色谱法（Ultra Performance Liquid Chromatography，UPLC）来测定巴氏杀菌乳和超高温灭菌乳中β-乳球蛋白的含量。结果表明：采用校准曲线法定量，检测到标准工作溶液变异系数（CV）在0.04%~0.23%之间，R2=1.00；超高温灭菌乳β-乳球蛋白的平均加标回收率在97.15%~99.11%之间，变异系数（CV）在0.53%~0.71%之间；巴氏杀菌乳β-乳球蛋白的平均加标回收率在96.56%~98.43%之间，变异系数（CV）在0.04%~0.15%之间；β-乳球蛋白方法检出限为20.41 mg/kg（S/N=3），方法定量限为61.23 mg/kg，符合GB/T 27417-2017《合格评定 化学分析方法确认和验证指南》标准要求。该方法简便易行、定量准确、精密度好，可用于液态乳中β-乳球蛋白的定量分析测定。
The heat treatment degree of milk can be determined by measuring its β-lactoglobulin content. In this paper, rapid and sensitive ultra performance liquid chromatography was used to determine the β-lactoglobulin contents in pasteurized milk and ultra-high temperature processed milk at a 210 nm detection wavelength. Results show that, when the calibration curve method is used for quantitative analysis, the coefficients of variation (CV) of the standard working solutions lie between 0.04% and 0.23%, and R2=1.00. The average spiked recovery of β-lactoglobulin in ultra-high temperature processed milk is 97.15%~99.11%, and the CV is between 0.53% and 0.71%. Meanwhile, the average spike recovery of β-lactoglobulin in pasteurized milk is between 96.56% and 98.43%, and the CV lies within 0.04%~0.15%. For the proposed method, the detection limit of β-lactoglobulin is 20.41 mg/kg (S/N=3), and the limit of quantification is 61.23 mg/kg. These meet the standard requirements listed in GB/T 27417-2017, Guidelines for validation and verification of chemical analysis methods for conforming assessments. In short, the proposed method is simple, relatively easy to implement, accurate, precise and can be used for the quantitative analysis and determination of β-lactoglobulin in liquid milk.