啤酒和麦汁中反-2-壬烯醛前体物质检测方法的优化及应用

对固相微萃取-气质联用法（SPME-GC-MS）测定啤酒或麦汁反-2-壬烯醛前体物质的方法进行了优化，分别研究了前处理保护气种类、流速、通气时间、反应体系pH值和加热环境对反-2-壬烯醛前体物质转化效果的影响。结果表明，选择保护气为氮气、气体流速为2 mL/s，通气时间为3 min最为合适；反应体系pH值在4.5时转化率最高，加热环境油浴效果要好于水浴。通过验证试验得出上述各条件优化后，转化率提高了19.49%，说明该方法较传统方法的转化率大大提高，可用于啤酒生产中对啤酒老化潜在隐患的预判。

Optimization and application of detection method for trans-2-nonenal precursor in beer and wort

The detection method of trans-2-nonenal (T2N) precursor in beer or wort was optimized using SPME-GC-MS. The effect of pre-treatment protective gas species, aeration time, aeration duration, reaction system pH and heating environment on the transformation of T2N precursor was studied. Results showed that the most appropriate conditions were protective gas N2, flow rate 2 ml/s and aeration time 3 min. When the reaction system pH was 4.5, the transformation rate was the highest, and the effect of using oil bath was better than using water bath. After verification test with above conditions, the transformation rate had improved 19.49%. It proved that the optimized method was better than the traditional method, which can be used in judging potential risk of beer aging.