苹果酒发酵过程中关键特征香气生成机制与多尺度在线控制方法

The aroma is a major factor that affects the quality of cider. The rapid development of cider-related industries in China was seriously hampered because of the insufficient aroma of cider. Study focused on formation mechanism and control method for aroma compounds during cider fermentation is thus considered to be a reasonable solution for improving the aroma quality of cider. In this study, according to instrumental analysis combined with sensory analysis, the characteristic aroma compounds will be investigated by the SPME-GC-MS/O with odor activity value(OAV),and the model of pattern recognition on characteristic aroma compounds will be established by fuzzy comprehensive evaluation(FCE). Moreover, proteomics research will be carried out by iTRAQ for investigating the characteristic aroma formation mechanism in the level of precursor substances and key enzymes. Calibration models of routine parameters and characteristic aroma cluster during cider fermentation will be established based on Fourier Transform Near Infrared Spectroscopy(FT-NIRS), and fermentation process kinetics will also be studied by the FT-NIRS models to monitor and measure the change mechanism of relative parameters. The measurement and analysis of micro and macro metabolic fluxes in cider fermentation process will be carried out for furtherly establishing on-line multiscale control method based on FT-NIRS.

香气是影响苹果酒质量的主要因素，苹果酒香气不突出是制约产业快速发展的主要瓶颈问题，亟待开展香气生成机制与控制方法的研究来解决该问题。据此拟利用固相微萃取气相色谱质谱/嗅觉测量法（SPME-GC-MS/O）与阈值分析法相结合，在定量分析香气活性值(OAV)基础上，利用模糊综合评判法建立关键特征香气模式识别模型；利用蛋白组学iTRAQ解析发酵过程中关键酶系的变化，结合关键特征香气及前体物质的变化，并关联相关代谢流的分析，探明苹果酒发酵过程中关键特征香气的生成机制；利用傅里叶变换近红外光谱法（FT-NIRS）建立苹果酒发酵过程常规参数和关键特征香气簇的快速检测模型，在此基础上，建立基于FT-NIRS的苹果酒发酵过程动力学模型；通过对苹果酒酵母生长过程中微观生理代谢流和发酵过程中宏观代谢流进行系统分析，建立基于FT-NIRS的苹果酒发酵过程多尺度在线控制方法，为实现全程质量在线控制与优化奠定基础。

我国是世界最大的苹果生产基地，但由于深加工产品单一，严重制约我国苹果种植业和加工业的深度发展，而苹果酿酒能够带动苹果产业的多元化发展。苹果酒是世界上仅次于葡萄酒的第二大果酒，但香气不足严重制约苹果酒的发展，因此开展酿酒酵母（Saccharomyces cerevisiae）合成苹果酒特征香气的代谢机制研究十分必要，找到其合成过程的中间产物及酶类、探明其代谢机制，以便更好的控制苹果酒香气形成。本研究在探明苹果酒特性香气的基础上， 通过解析发酵过程中关键酶系的变化，结合关键特征香气及前体物质的变化，并关联相关代谢流的分析，探明苹果酒发酵过程中关键特征香气的生成机制；利用傅里叶变换近红外光谱法（FT-NIRS）建立苹果酒发酵过程关键特征香气簇的快速检测模型，在此基础上，建立基于FT-NIRS的苹果酒发酵过程动力学模型；通过对苹果酒酵母生长过程中微观生理代谢流和发酵过程中宏观香气代谢流进行系统分析，建立基于FT-NIRS的苹果酒发酵过程多尺度在线控制方法，为实现全程质量在线控制与优化奠定基础。