糠壳是浓香型白酒酿造中必不可少的固态填充剂和膨松剂。该研究采用实际生产用酒甑清蒸生糠壳,获得了糠壳清蒸过程中不同时间节点(2~90 min)的馏液,并利用液液萃取-气相色谱-质谱联用技术分析了馏液中的香气成分。结果表明,糠壳中香气成分总含量随蒸馏时间的增加而减少。醇类、吡嗪、萜烯化合物含量随蒸馏时间增加均呈减少趋势。醛类化合物在前5 min内含量略有增加,5 min后则递减。内酯类化合物(γ-丁内酯、γ-戊内酯、γ-己内酯、γ-壬内酯)、糠醛、植酮和香草醛的含量随蒸馏时间的增加而增加。主成分分析结果表明,前15 min内和60~90 min范围内的糠壳蒸馏样分别指向青草味-土腥味等和甜香味特征物质。该研究首次报道了蒸糠过程中香气成分的变化规律,为实际生产中科学调控蒸糠过程提供了理论与数据支撑。

The rice husk is the necessary solid filler and leavening agents for Chinese Strong-aroma liquor.In this study,the raw rice husk was distilled by factory-level Zengtong(distilling apparatus),and the distillates were collected in specific distillation time points.The liquid-liquid extraction and gas chromatography-mass spectrometry were applied to semi-quantify the aroma compounds in distillates.The results showed that total concentration of aroma compounds decreased with the distillation time.Concentrations of alcohols,pyrazines and terpinoids decreased with the distillation time.Concentration of aldehydes increased 5 min and decreased after that.Concentrations of lactones(including γ-butyrolactone,γ-valerolactone,γ-hexalactone and γ-octalactone),furfural,phytone and vanillin increased with the distillation time.Results of principal component analysis showed that samples collecting 20 min and after 60 min positively related with compounds with green-earthy odor and sweet odor,respectively.The variation of aroma compounds during rice husk distillation was reported for the first time and it provide important data and reference for the quality control of rice husk distillation.