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Vinegar from TongBao Group Limited was used as specimen. This study adopts subzero treatment、 high-temperature processing、microwave treatment and ultrasonication to made a research into artificial aging of vinegar. The content of the total acid、total ester, amino nitrogen、reducing sugar, nonvolatile acid were determined by national standard methods. The optimum conditions of artificial aging were determined. The main results were as follows:1. After subzero treatment at-5℃,0℃,5℃on vinegar, the results indicated:at temperature of-5℃, the content of total acid was invariable, the content of total ester decreased slight, the content of amino nitrogen increased, the content of reducing sugar and fixed acid decreased. It showed clearly that After subzero treatment, the composition of vinegar changed in respect of physical and chemical.It leads to dynamic changes of the contect of vinegar component. At0℃, each index was less influenced, stability of the quality of vinegar was fully guaranteed.2. After high-temperature processing at30℃,35℃,40℃on vinegar, the results indicated:at30℃, the content of total acid decreased, the content of amino nitrogen increased slightly, the content of reducing sugar and fixed acid decreased. It showed that after high-temperature processing, chemical go in the different direction. At35℃, the variation was more approach to the reasonable expectation. At35℃,it were suitable to aging vinegar.3. After microwave treatment of different power, the content of total acid increased, the quantitative value increased by27.15%. By using single-factor experiments and response surface method, the optimum technological conditions of aging vinegar were as follows:time of microwave treatment was2.99mim, the power was716.90W, volume of vinegar was85mL. According to Design Expert8.0.6.1, the predict concentration of total ester was16.1556g/L. Verifying test results showed that the concentration of total ester was16.11g/L, the two of them are very close, it proved that test results are reasonable and practical. After microwave treatment, the color, flavor and taste of vinegar took a turn for the better. 4. After ultrasonication of different power, the content of total acid increased, the quantitative value increased by8.29%. By using single-factor experiments and response surface method, the optimum technological conditions of vinegar were as follows:the power was707.25W, ethanol concentration was0.51%, time of ultrasonication was20mim. According to Design Expert8.0.6.1, the predict concentration of total esterwais13.79g/L. Verifying test results and the predict concentration were very close, it proved that test results are reasonable and practical. After ultrasonication, the color, flavor and taste of vinegar took a turn for the better.
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