白酒中酯类化合物手性异构体风味特征及其对酒体风味贡献研究

Chiral compounds of esters in Chinese Liquor play an important role in the formation of its flavor and aroma. However, the composition and content of chiral stereoisomers as well as the flavor characteristics of each enantiomer and its contribution to the flavor are not clear. In this project, the flavor charactristcs of stereoisomers of chiral compounds of esters and its contribution to the whole flavor of Chinese Liquors, including strong aroma, light aroma and soy sauce aroma type liquors will be studied. Firstly, optimizing the preprocessing way to develop an effective method for the extraction of esters chiral compounds. Then establishing a high efficient method to separate the enantiomers of ester compounds by chiral gas chromatography. Using solid-phase microextraction(SPME) and liquid-liquid extraction(LLE) coupled with GC-MS and GC-FID to identify and quantify the chiral isomers of esters compounds, getting its composition and content in Chinese Liquor on the basis of above research. The flavor characteristics of each stereoisomer will be investigated by chiral GC-olfactometry(GC-O) method. The contribution of the stereoisomers to the whole flavor of Chinese Liquor is going to be explored by means of sensory evaluation such as aroma recombination, omission and triangular experiments. The conduction of this project will be helpful for the deep-insight understanding of flavor components of Chinese Liquor, distinguishing its adulteration, improving its flavor and establishing its product standard.

白酒中酯类手性化合物对酒体风味形成及香型构成具有重要作用，但其手性异构体的组成和含量尚不清楚，各个异构体的风味特征及其对酒体的风味贡献尚不明确。本项目拟以浓香、清香、酱香三种香型名优白酒中酯类手性化合物为研究对象，优化白酒前处理方法，建立酯类手性化合物有效提取方法；通过手性气相色谱法建立白酒中酯类化合物手性异构体分离方法，实现各个异构体高效分离；在此基础上，利用SPME-GC-MS、LLE-GC-MS及GC-FID等方法定性定量分析白酒中酯类化合物手性异构体，明晰其各个异构体的组成及含量；通过手性GC-O测定各个立体异构体的风味特征；利用香气重组和缺失实验及三角实验等感官评价手段探索各个异构体对酒体风味的贡献，明晰起香气活性作用的异构体。本项目的实施将为深入认识我国白酒风味成分及白酒鉴伪、风味改善、产品标准建立提供科学数据。

白酒中酯类手性化合物对酒体风味形成及香型构成具有重要作用，但其手性异构体的组成和含量尚不清楚，各个异构体的风味特征及其对酒体的风味贡献尚不明确。本项目以浓香、清香、酱香三种香型名优白酒中手性化合物为研究对象，建立了乳酸乙酯、3-羟基丁酸乙酯、1,2-丙二醇、乳酸这几种手性化合物的有效提取和色谱分离方法；实现了白酒中这些手性化合物各个异构体的高效分离；然后利用DI-GC-MS、LLE-GC-MS及GC-FID结合标准曲线法定性定量明晰了白酒中这几种手性化合物异构体的分布及含量；再通过手性GC-O测定了手性立体异构体的风味特征；结合感官评价手段探索了手性立体异构体对酒体风味的贡献。研究结果表明，在所研究的大部分纯粮发酵白酒中，乳酸乙酯以(R)-构型为主，而乳酸乙酯香料勾兑的白酒中以(S)-构型为主。在研究的白酒中3-羟基丁酸乙酯以(R)-构型为主。1,2-丙二醇在酱香型白酒中(S)-构型占优势，浓香型中(R)-构型为主，清香型中没有检测到。所研究的大部分白酒中乳酸以D-乳酸为主。乳酸乙酯、1,2-丙二醇的两个异构体的香气特征和阈值均不同。通过本项目的实施为深入认识白酒风味成分及鉴别纯粮发酵白酒鉴伪和为相关酒企规范生产提供了监控数据。