Antioxidant activity of phenolic compounds of grape pomace (Research note)

In this experiment، acetone was used to extract the phenolic compounds of grape pomace by colorimetric method (Folin-Ciocalteu). The phenolics extract levels of 50، 150، 250 and 350 ppm were used to assess their antioxidant activity in raw soybean oil. On day 0، 4، 8 and 12 the proxide value for soybean oil was estimated. Also، the TBA value for soybean oil on day 0، 5، 9 and 13 was estimated. The results showed that the phenolic compounds whose content in grape pomace is 64 g/kg DM has an antioxidant activity. The level of 150 ppm of tannin extract from grape pomace showed a desirable activity to prevent the oxidation of raw soybean oil. The antioxidant activity of this level was higher than those obtained by the level 200 ppm from synthetic antioxidants. Therefore، the use of phenolic compound in grape pomace as natural antioxidants can be recommended.