目的:建立柱前衍生-反相高效液相色潽法测定乳及乳制品中L-羟脯氨酸含量。方法:乳及乳制品中蛋白质经酸水解后,用2,4二硝基氟苯对L-羟脯氨酸进行衍生,采用250 mm×4.6 mm,5μm Dia-monsilAAA分析柱进行分离,检测波长360 nm,流动相为0.02 mol/L磷酸氢二钠与磷酸二氢盐缓冲液、乙腈、甲醇,流速1.0 ml/mim,采用梯度洗脱。结果:L-羟脯氨酸的浓度与峰面积成良好的线性关系,相关系数r为0.9994,回收率在94.0%～97.4%之间,样品的测定结果良好。结论:本方法测定乳及乳制品中L-羟脯氨酸灵敏度较高,干扰因素少,结果稳定、准确,适合乳及乳制品中L-羟脯氨酸的测定。 Objective: To establish a pre - column derivatization - RP - HPLC method for the determination of L - hydroxyproline in milk and dairy products. Methods: L-Hydroxyproline was derivatized with 2,4 dinitrofluorobenzene by acid hydrolysis in milk and dairy products, and then separated using a 250 mm × 4.6 mm, 5 μm Dia-monsilA AA analytical column. The detection wavelength 360 nm, mobile phase 0.02 mol / L disodium hydrogen phosphate and dihydrogen phosphate buffer, acetonitrile, methanol, flow rate 1.0 ml / mim, using a gradient elution. Results: The linear relationship between the concentration of L-hydroxyproline and the peak area was obtained. The correlation coefficient r was 0.9994, the recoveries were in the range of 94.0% -97.4%, and the determination results were good. Conclusion: This method is suitable for the determination of L-hydroxyproline in milk and dairy products with high sensitivity and few interference factors. The results are stable and accurate.