以山西老陈醋为原料,微波消解法处理样品,采用原子吸收光谱法对Zn、Fe、K、Ca、Mg 5种微量元素含量进行测定.通过混酸体系、混酸体积比、样液与消解液体积比和消解时间单因素试验,利用正交试验确定微波消解处理样品的最佳条件.结果表明,在以HNO3-H2O2为消解试剂的混酸体系中,Zn、Fe、K、Ca四种微量元素最佳消解条件为混酸体积比7∶1,样液与消解液体积比1∶4,消解时间为20 min;微量元素Mg最佳消解条件为混酸体积比7∶1,样液与消解液体积比1∶4,消解时间为25 min,在此条件下,测得样品回收率在95.0％～106.0％,精密度试验结果相对标准偏差为0.42％～1.13％.优化后的微波消解法具有反应快、消解彻底、精密度好、准确度高等特点,为进一步研究和分析山西老陈醋的营养价值提供参考.%Using the Shanxi aged vinegar as the raw material,the simple was treated by microwave digestion method and the contents ofZn,Fe,K,Ca and Mg were determined by atomic absorption spectrometry method.On the basis of single factor experiments of mixed acid system,mixed acid volume ratio,simple-digestion liquid volume ratio and digestion time,the optimum conditions of microwave digestion were determined.Results showed that with HNO3-H2O2 as digestion reagents in mixed acid system,the optimum digestion conditions of four trace elements (Zn,Fe,K,Ca) were mixed acid volume ratio 7∶1,simple-digestion liquid volume ratio 1∶4 and digestion time 20 min;the optimum digestion conditions of trace element (Mg) were mixed acid volume ratio 7∶1,simple-digestion liquid volume ratio 1∶4 and digestion time 25 min.Under the conditions,the recovery rate was 95.0％-106.0％,the relative standard deviation (RSD) of precision tests results was 0.42％-1.13％.After optimization,the microwave digestion method was fast,eliminate digestion,good precision,high accuracy and so on,which provided reference for further research and nutritive value analysis of Shanxi aged vinegar.
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