Abstract: A reversed-phase high performance liquid chromatographic (HPLC) method was established for the determination of erythrosine in fermented milk. After enzymatic hydrolysis, the sample was extracted with anhydrous ethanol, and purified by solid phase extraction using an HLB column under alkaline conditions. The separation was performed on a C18 reversephase column by gradient elution using a mobile phase comprising 20 mmol/L ammonium acetate buffer solution (pH 6.5) and methanol. The detection wavelength was set at 520 nm, and quantification was performed by the external standard method. The results showed that the linear range for erythrosine was 0.05–20.00 μg/mL. The limit of quantitation (LOQ) and the limit of detection (LOD) of erythrosine in fermented milk samples were 0.2 and 0.1 mg/kg, respectively. The recoveries from fermented milk samples spiked at levels of 0.2–2.0 mg/kg were 96.5%–105.6%, and the relative standard deviations (RSD) were 1.87%–2.21%. The method is simple and accurate, has high recovery and good repeatability, and is suitable for the determination of erythrosine in fermented milk.

Key words: CHEN Jing, DUAN Guoxia, LIU Lijun, LI Cuizhi*, Lü Zhiyong

摘要： 建立发酵乳中赤藓红的反相高效液相色谱分析方法。使用酶法分解蛋白，无水乙醇作为提取剂，碱性条件下使用HLB固相萃取小柱净化，以C18反相色谱柱分离，20 mmoL/L乙酸铵缓冲溶液（pH 6.5）-甲醇为流动相，采用梯度洗脱，检测波长520 nm，外标法定量。结果表明：赤藓红在0.05～20.00 μg/mL线性良好，发酵乳样品中赤藓红的定量限为0.2 mg/kg，检出限为0.1 mg/kg；发酵乳中赤藓红的添加量为0.2～2.0 mg/kg时，加标回收率为96.5%～105.6%，相对标准偏差为1.87%～2.21%。本方法操作简便、结果准确、回收率高、重复性好，适用于发酵乳中赤藓红的含量测定。

关键词: 发酵乳；反相高效液相色谱法；赤藓红；固相萃取；木瓜蛋白酶