The Variation Of The Flavors And Functional Factors During The Production Of Zhenjiang Vinegar

Zhenjiang Hengshun Vinegar was one of the Chinese famous vinegars. It is well known for its special qualities and bioactivities in the world. So, the researches about flavors and functional factors in Zhenjiang vinegars are of important. In this study, we analyzed the flavors and functional factors in Zhenjiang vinegars of different aging times, different seasons and different methods of storaging. Also, the mechanisms of the variation of the functional factors in Zhenjiang vinegars were discussed.The volatile flavor compounds and other kinds of flavor compounds in Zhenjiang vinegars were analyzed by head space-solid phase microextraction-gas chromatogragh-mass spectrum (HS-SPME-GC-MS), amino acid anaylyzer and HPLC. Also, the contents of functional factors in Zhenjiang vinegars such as tetramethylpyrazine, flavones and polyphenols were analyzed by HPLC and colorimetric method.Though the tests of vinegar of different aging time, we found that the amounts of reducing sugar and free amino acids decreased during aging. Also, the volatile flavor compounds such as alcohols and acids decreased, but the contents of esters and hetero- geneous ring compounds though the 3.98% and 1.56% in new vinegar increased to 13.76% and 14.48% after six years. The results also showed that the amounts of tetramethylpyrazine increased with the aging processing. The contents of tetramethylpyrazine was 34.70 mg/L at initial time, but increased to 696.73 mg/L six years later. The total flavones and polyphenols decreased at initial time, however, increased at final time. Maillard's reaction might be the most important reason for the increased of the tetramethylpyrazine. The changes of total flavones and polyphenols were supposed to the results of degradation and complexation in Zhenjiang vinegars during aging.The vinegars which were produced in three years of different seasons were determined. The results showed that amounts of the total acids, reducing sugar and free amino acids in spring and winter were higher than those in summers and autumns.We also found that the esters in volatile flavor compounds were enriched in the samples which were produced in springs and winters. However, the vinegar samples of summers and autumns have a large number of functional factors.Though the determination of vinegar samples which were storaged in different containers, we found that the vinegar which was sroaged in pottery has more numbers of flavors and functional factors because pottery contains more air and metal elements.