Changes of Bioactive Components and Antioxidant Activities about Ginger Jiaosu During the Fermentation Process

Ginger was used as the raw material for fermentation, the ginger jiaosu was manufactured by compound bacteria fermentative of yeast, Lactobacillus paracasei and acetic acid bacteria (Hu Niang 1.01).Samples were taken periodically to determine the changes in contents of 6-gingerol and gingerol to characterize the changes in biological activity of ginger fermentation process. The content of total phenols and flavonoids was measured during fermentation. And the changes of DPPH radical scavenging rate were used to characterize the changes in antioxidant activity during ginger fermentation. The results showed that, during the 15 days of fermentation of ginger jiaosu, the pH of the fermentation were declined eventually to 3.51, the 6-gingerol's content reached the highest pot, 130.02 μg/mL, at the second day. The total content of gingerols reached the highest level on the 4th day, which was 2.46%, and the whole content increased from 2.24% to 2.40%. Being counted as rutin, the highest content of flavonoids about the antioxidant index was 0.131 mg/g on the second day, and after that, the content got slightly reduced, and the DPPH free radical scavenging rate was increased in the six days during the beginning of fermenting, and got the highest level, 94.33%, on the 6th day. The trend of the scavenging rate the total phenolics was the same as that of DPPH free radical. At the end of fermentation, being counted as gallic acid, the content of total phenolicswas increased by 0.02 mg/g.Both of measured datas showed that the antioxidant activity of ginger jiaosu would remaine well in the fermentation process.