A high performance liquid chromatographic method was developed for the determination of total acetoin in wine using 2, 4-dinitrophenylhydrazine(DNPH) derivatization. The experimental con ditions, including pH value, reaction time, DNPH content, reaction temperature and processing step after derivatization, were optimized. The derivatization products were separated on an Ultimate C18 column (4. 6 mm x250 mm, 5 μm) using acetonitrile -water (55 : 45) as mobile phase at a flow rate of 1. 0 mL/min. The oven temperature was set at 30℃, and the detection wavelength was 363 nm. Under the optimal conditions, the linear range for acetoin was in the range of 0 -40. 0 mg/L with correlation coefficient of 0. 999 9. The spiked recoveries of acetoin in the dry red wine sample were in the range of 95% - 106% with relative standard deviations (RSDs) of 2. 3% - 3. 4%, and the spiked recoveries of the dry white wine samples were in the range of 94% - 104% with RSDs of 2. 5% - 3. 1% . The contents of acetoin in some different types of wine samples were tested, and the results showed that the concentrations of total acetoin in domestic fake and shoddy wine samples were much higher than those in good quality wine samples. Besides, the concentration of total acetoin in home-brewed wine samples from badgrapes were also higher. Therefore, the concentration of total acetoin can provide a reference for the wine quality identification.%建立了测定葡萄酒中总乙偶姻含量的2,4-二硝基苯肼衍生/高效液相色谱法,确定了2,4-二.硝基苯肼(DNPH)进行柱前衍生的最佳酸度、反应时间、DNPH用量、反应温度及衍生后处理步骤.采用UltimateC18柱(4.6 mm×250 mm,5μm)对衍生产物进行分离,流动相为乙腈-水(55∶45),流速1.0 mL/min;柱温30℃；检测波长363 nm.在优化条件下,乙偶姻在0～40.0 mg/L范围内呈良好的线性关系,相关系数为0.9999.干红葡萄酒样品的加标回收率为95％ ～ 106％,相对标准偏差(RSD)为2.3％ ～ 3.4％；干白葡萄酒的回收率为94％ ～ 104％,RSD值为2.5％ ～3.19％.对几种不同种类葡萄酒的总乙偶姻含量进行测定,结果显示国产伪劣葡萄酒及自酿腐败葡萄酒中总乙偶姻的含量明显高于合格葡萄酒.乙偶姻的含量可为葡萄酒的品质鉴定提供参考.
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