富含蛋白食品中的8种合成色素的高效液相色谱测定方法

Determination of 8 synthetic food colorants in protein-rich samples with high performance liquid chromatography

目的建立高效液相色谱法测定富含蛋白食品中合成色素的方法。方法样品匀浆后采用乙醇:氨水:水(7:2:1)溶液提取,经低温冷冻去除蛋白后,水浴加热浓缩除氨,采用聚酰胺固相小柱萃取净化,以甲醇和20mmol/L乙酸铵溶液为流动相,通过Agilent extend-C18色谱柱梯度洗脱分离,可见光区段多波长信号检测柠檬黄、日落黄、苋菜红、胭脂红、赤藓红、诱惑红、亮蓝、靛蓝8种合成色素,保留时间定性、外标法定量。结果建立的测定8种合成色素的方法在0.6~10 mg/kg内曲线线性关系良好,相关系数为0.995以上,检测限介于0.1~0.4 mg/kg,不同加标浓度下回收率介于75%~95%之间,变异系数在3.6%~9.3%之间。结论该方法用于高蛋白食品中合成色素的测定,具有操作简便、灵敏高、准确性好、无杂质干扰等优点。

Objective To establish a method for the detection of synthetic colorants in protein-rich processed food with high performance liquid chromatography.Methods Sample homogenates were extracted by ethanol:ammonium hydroxide:water (7:2:1), and frozen for deproteinization, further incubated in water to remove ammonium, purified by solid phase extraction with polyamine column. Extract containing 8 synthetic colorants (lemon yellow, sunset yellow, amaranth, ponceau 4R, erythrosine, allura red, brilliant blue, and indigo carmine) was separated by Agilent extend-C18 with methanol and 20 mmol/L of ammonium acetate as the mobile phase. Compounds were detected under multi-wavelength measurement.ResultsMeasurement on 8 synthetic colorants with the developed method showed an excellent linear relationship between 0.6~10 mg/kg, with the correlation coefficient more than 0.995, and the limit of detection between 0.1~0.4 mg/kg. Under different spiked concentration, the recoveries were determined between 75%~95%, and relative standard derivations were between 3.6%~9.3%.Conclusion The developed method can be applied in the detection of synthetic colorants in protein-rich processed food, with easy operation, high sensitivity, excellent accuracy and less disturbance.