加入沉淀剂对高效液相色谱法测定果汁中苯甲酸、山梨酸含量结果的影响

目的研究加入沉淀剂对高效液相色谱法(high performance liquid chromatography,HPLC)测定果汁中苯甲酸、山梨酸含量的结果的影响。方法按照GB 5009.28-2016《食品安全国家标准食品中山梨酸、苯甲酸的测定》中高效液相色谱法测定果汁样品中检测苯甲酸、山梨酸含量,通过加入沉淀剂对其前处理方法进行优化。结果加入沉淀剂后,苯甲酸回收率在99.01%-105.15%之间,相对标准偏差(relative standard deviation,RSD)均小于5.86%,山梨酸回收率在93.13%-98.9%,RSD小于6.23%。同一试样苯甲酸重复性实验CV值为0.03%、山梨酸为0.00%。结论本研究建立的方法加入亚铁氰化钾和乙酸锌后沉淀物较多,能够减少杂质干扰物的影响,检测结果稳定,适用于果汁中苯甲酸、山梨酸含量的检测。

Effect of precipitating agent on determination of benzoic acid and sorbic acid in fruit juice by high performance liquid chromatography

Objective To study the effect of adding precipitate dose on the determination of benzoic acid and sorbic acid in fruit juice by high performance liquid chromatography (HPLC). Methods According to GB 5009.28-2016 National food safety standard-Determination of sorbic acid and benzoic acid in foods, the samples were determined by HPLC and the pretreatment method was optimized by adding precipitating agent. Results After the addition of precipitating agent, the recovery rates of benzoic acid were 99.01%-105.15% at the spiked levels and the relative standard deviations (RSDs) were less than 5.86%; the recovery rates of sorbic acid were 93.13%-98.9%, and the RSDs were less than 6.23%. The CV (%) value of benzoic acid in the same sample was 0.03% and sorbic acid was 0%. Conclusion The addition of potassium ferrocyanide and zinc acetate resulted in more sediment, which can reduce the effect of interferon. The results are stable and it is suitable for the determination of benzoic acid and sorbic acid in fruit juice.