The Effect of Gamma Irradiation on Some Physicochemical, Microbial Properties and Antioxidant Activity of Dried Grape Marc (Vitis vinifera L. var. Siahe sardasht)

In order to reduce microbial load in edible and medicinal plant products, gamma irradiation is used. On the other hand, there is the risk of structural changes in the composition of chemical compound due to gamma irradiation. The purpose of this study was to evaluate the effect of gamma irradiation on the physicochemical, microbial properties, and antioxidant activity of dry red grape marc. Samples of dry black grape marc were exposed to gamma irradiation at doses of 0, 10 and 25 kGy. Microbial load, pH, color, DPPH radical scavenging and total phenolic content of treated samples were measured and compared with control (Non- irradiated sample). The results showed that exposure to a dose of 25 kGy did not have a significant effect on pH (p