Phenolic Compounds and Antioxidant Properties of Grape Pomaces Fermented by Aspergillusoryzae

A central composite design (CCD) was used to evaluate the effect of temperature, time, solvent concentration and whey protein powder on the phenolic compounds content, flavonoids content, FRAP and DPPH radical scavenging activity of grape pomace fermented by A. oryzae . The phenolic compounds content ranged from 18.04-90.23mg/g, the flavonoids content from10.5-71.81mg/g, FRAP from 85-203µmol/g and DPPH from 18.19-87.9%. Results of the CCD showed that temperature had a positive effect on phenolic compounds and flavonoids content and a negative effect on DPPH and FRAP. Time and solvent concentration had a positive effect on all of the responses. Whey protein powder had a negative effect on all of the responses.