Abstract: Human excrement extract was used as the inoculum to modify grape pomance dietary fiber in a mimic human intestinal environment by in vitro fermentation. The pH and the content of short-chain fatty acids (SCFAs) in modified dietary fiber obtained after different times of fermentation were determined. The results indicated that grape pomance dietary fiber was one of ideal carbon sources that could be exploited by intestinal microflora. SCFAs including acetic acid, propionic acid, butyrate acid and isobutyrate acid were produced during fermentation in vitro. Meanwhile, no obvious pH change in the fermentation broth of modified grape pomace dietary fiber was observed. However, the contents of total SCFAs and each SCFA were affected due to fermentation treatment.

Key words: grape pomace, modified dietary fiber, in vitro fermentation, short-chain fatty acids