| A high performance liquid chromatographic method was developed for the determination of total acetoin in wine using 2-4-dinitrophenylhydrazine(DNPH) derivatization.The experimental conditions,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×250 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. |