For 12 kinds of brewing vinegar in four brands and different years which were purchased from market, the analysis of the changes in their six indexes were performed, which include total polyphenols, flavonoids, total oxidation value, 1,1-diphenyl-2-picrylhydrazyl free radical(DPPH·), hydroxyl free radical (·OH) and superoxide anion (O2-·) clearance. And by analyzing correlation, doing principal component analysis,their antioxidant properties were evaluated. The results showed that with the aging time increasing, the clearance rate of three f...
