| China has been the biggest apple producer in the world since 1992, and the apple is overproduced now. Apple wine including cider is one of the main form of apple processing, therefore, apple wine-making using present apple cultivars as material should be the topic of apple wine research.Apple wine of high quality should be characterized by 'spicy, greater aromatic, appley note', bitter, and astringent to different extent, among which characterization of 'spicy, greater aromatic, appley note' was often expressed as 'fruity'. In this paper, the objective of this study was to control fruity character of apple wine using present apple cultivars in our country as raw material by apple cultivar and yeast, and the influence of apple cultivar and yeasts preserved in our laboratory on volatiles of apple wine, the enological characterization of the corresponding apple cultivar and yeasts, and the synthetic pathway of important volatile component in one yeast were investigated. The main contents of this dissertation is as follows:(1) A rapid, simple, small volume of sample, and solvent-free method for determination of aroma compounds for apple wine was developed. The analysis was performed with headspace carboxen-PDMS solid-phase microextraction coupled with gas chromatography–mass spectrometry. The regression coefficients for curves for eighteen analytes including eight esters, six alcohols, and four lower fatty acids which represent several major classes of aroma compounds in apple wine and apple juice were above 0.9112, the recoveries for all this anayltes ranged from 80.23 % to 110.21 % with a relative standard deviation from 1.5 % to 6.4%, domenstrating that the SPME method was suitable for the determination of volatiles in apple wine with ethanol level below 12 %(v/v) such as cider and in apple juice, and it could also be used to monitor the formation of esters, alcohols, and lower fatty acids in apple juice fermentations simultaneously, which will provide greater insight into yeast metabolism and flavor formation in the future. The main parameters of this method were: 75 μm Carboxen-PDMS fiber, extraction time: 40 min, extraction temperature: 45℃, NaCl concentration: 25%, desorption time: 3 min. (2) The enological characterization of main apple cultivars of our country was studied systematically, according to the cider apple classification guideline of Britain, all apple cultivars except Granny Smith in our country belong to sweet variety. The most production cultivar Fuji in China has the lowest acids, the lowest polyphenol, the highest sugar among the present culitvars. In addition, all apple cultivars except Gala belong to 'ester type' cultivar, and Gala belong to 'alcohol type' cultivar.(3) According to result of QDA (quantitative descriptive analysis),the fruity intensity of apple wines by different cultivars from strong to weak was: W.W.Pearmain, Starking, Red Deli., Granny Smith, Shanxi Fuji, Jonared, Shandong Fuji, Gala, Golden Deli., Ralls. By PCA (Principal components analysis) of all esters and alcohols identified in all these apple wines, it was concluded that there was no 'impact' aroma component attributing to the perceived aroma, and the perceived aroma was the result of a pattern of all esters and alcohols existing in apple wines, as a result, 10 relative important compounds were selected by means of loading coefficient. Combined the information of PCA with odour value, 2-phenethyl acetate was the most important component among the 10 relative important compounds regulating aroma character of apple wine made by different cultivar, while amyl alcohol was the most important component differentiating aroma character of apple wine made by different cultivar. (4) For most apple wines, esters and alcohols were mainly produced during fermentation, between which alcohols derived more from fermentation. Esters and alcohols from fermentation accounted for 50.92-99.09%,40.59-93.45% of total esters and alcohols in apple wines respectively, that is, 0.91-49.08%,6.55-59.41%...
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