基于HS-SPME-GC-TOFMS分析不同品种酿酒大米的挥发性成分差异

Differential analysis of volatile components in different varieties of brewed rice by HS-SPME-GC-TOFMS

大米是白酒的主要原料和风味物质来源,为了探明不同酿酒大米之间的挥发性成分差异,为白酒生产过程中的工艺优化提供参考,采用顶空固相微萃取-气相色谱-飞行时间质谱(HS-SPME-GC-TOFMS)法对11种大米的挥发性成分进行检测,结合聚类热图、感官评价、气味活性值(OAV)分析挥发性成分对大米整体香气的影响。结果表明,11种大米中共鉴定出78种挥发性成分,其中醇类11种,酮类15种,醛类17种,酯类15种,杂环类8种,其他类12种。聚类热图显示,不同大米样品之间的挥发性成分含量差异较大,以酯类、杂环类和酮类含量较高。感官评价发现,南粳9108大米的得分最高,宁9044大米最低。通过OAV计算,筛选出1-辛烯-3-酮、癸醛、己酸乙酯、乙酸戊酯和2-乙酰基-1-吡咯啉5种成分,其OAV>1.000,对大米整体香气的贡献较大,其中感官得分最高的南粳9108大米中仅2-乙酰基-1-吡咯啉的OAV>1.000,其他成分的OAV均小于1.000,表明2-乙酰基-1-吡咯啉是呈现大米香气的关键物质。综上,11种不同品种大米之间的挥发性成分数量、含量、感官评分及主要呈香成分差异较大,感官评分较高、饭香浓郁的南粳9108大米更适合用作酿酒大米。

Rice is the main raw material and flavor source for Baijiu.To investigate the differences in volatile components among different brewing rice and provide reference for process optimization in Baijiu production,headspace solid phase microextraction-gas chromatography-time-of-flight mass spectrometry(HS-SPME-GC-TOFMS)was used to examine the volatile components of 11 cooking rice species,and the influence of volatile components on the overall aroma of rice was analyzed by cluster heat map,sensory evaluation,and odor activity value(OAV).The results showed that 78 volatile components were identified in 11 rice species,including 11 alcohols,15 ketones,17 aldehydes,15 esters,eight heterocycles and 12 others.The cluster heat map showed that the contents of volatile components varied greatly among different samples,and the contents of volatile components were mostly in esters,heterocycles and ketones.The sensory evaluation revealed that Nanjing 9108 scored the highest,and Ning 9044 scored the lowest.Through OAV calculation,five components,namely 1-octen-3-one,decanal,ethyl hexanoate,amyl acetate and 2-acetyl-1-pyrroline,were screened with OAV>1.000,which contributed more to the overall aroma of the rice.The OAV of 2-acetyl-1-pyrroline in Nanjing 9108 was more than 1.000,and the OAV of other components was less than 1.000,indicating that 2-acetyl-1-pyrroline was the key substance to present the aroma of rice.In conclusion,the quantity,content,sensory score and main aroma presenting components of volatile components varied greatly among 11 different varieties of rice,Nanjing 9108 with high sensory score and rich rice aroma was more suitable for use as wine-making rice.