HPLC法同时测定复合食品防腐剂中苯甲酸、山梨酸和脱氢乙酸

Determination of benzoic acid,sorbic acid and dehydrogenation acetic acid in food preservatives by high performance liquid chromatograph

应用高效液相色谱法测定复合食品防腐剂中苯甲酸、山梨酸和脱氢乙酸的含量。样品用水提取后,甲醇和0.02mol/L乙酸铵15∶85(v/v)为流动相洗脱,经Syncronis aQ(4.6mm×150mm,5μm)色谱柱分离,二极管阵列检测器检测,检测波长为225nm。苯甲酸、山梨酸和脱氢乙酸的质量浓度在2 50mg/L的范围内与其峰面积成线性关系,线性方程分别为y=38273x-8760.9、y=48559x+10538、y=52126x+4283.4,检出限均为0.1mg/L。苯甲酸平均回收率为98.8%101.0%,相对标准偏差≤1.8%(n=6);山梨酸平均回收率为97.5%100.1%,相对标准偏差≤2.2%(n=6);脱氢乙酸平均回收率为99.5%101.0%,相对标准偏差≤2.2%(n=6)。该方法精确度和准确性好、灵敏度高,样品预处理简单,避免了滴定分析方法中复配防腐剂之间相互干扰的问题,是复合食品防腐剂中各种成分含量测定的理想检测方法。

HPLC was applied to the determination of Benzoic acid, Sorbic acid and Dehydrogenation acetic acid in food preservatives. The sample was extracted with water and then separated by elution with methanol and 0. 02mol/L ammo- nium acetate mixed solutions 15 ： 85 （v/v） on Syncronis aQ （4. 6mm×150mm,5μm） column. The detector was diode array, detection wavelength was 225nm. Linear relationship between values of peak areas and mass concentra- tions of the Benzoic acid, Sorbic acid and dehydrogenation acetic acidwere obtained in the range of 2 - 50mg/L, the linear equations were y = 38273x - 8760. 9, y = 48559x ＋ 10538, y = 52126x ＋ 4283.4, detection limits were all 0. 1 mg/L. The values of average recoveries of Benzoic acid werein the range of 97. 5 % - 100. 1% , the valuesof RSDs wereless than or equal to 1.8% （ n = 6 ）. The average recoveries of Sorbic acid werein the range of 97.5% 100. 1% ; the values of RSDs wereless than or equal to 1.8% （n = 6）. The average recoveries of dehydrogenation acetic acid were in the range of 97. 5%~ 100. 1% , the values of RSDs were less than or equal to 1.8% （n =6）. This method is preciseand accurate, highlysensitive. Thesample pretreatment is simple. It overcomes food additives interfer- eneein titration analysis. This is an ideal method for determination of complex food preservatives.