Effects of gamma radiation, individually and in combination with bioactive agents, on microbiological and physicochemical properties of ground beef

Effects of gamma irradiation (2 kGy) on microbiological and physicochemical properties of ground beef were investigated individually or in combination with bioactive compounds consisting of cinnamaldehyde, ascorbic acid, and sodium pyrophosphate decahydrate. Meat samples were mixed with cinnamaldehyde (1.47%, w/w), cinnamaldehyde plus ascorbic acid (0.5%, w/w), or cinnamaldehyde plus sodium pyrophosphate decahydrate (0.1%, w/w), followed by irradiation at a dose of 2 kGy. Microbiological and physicochemical properties of samples were analyzed. The results demonstrated that combined treatments using irradiation and bioactive compounds could significantly decrease the microbial load of meat samples compared with that of the untreated control samples. Moreover, the combined treatments did not cause any significant changes in physical or chemical properties of meat samples. Irradiation, both with and without cinnamaldehyde treatment, caused significant increases in concentrations of thiobarbituric reactive substances and peroxide in treated samples, compared with the concentrations of these substances in the control samples; however, in the presence of ascorbic acid, the pro-oxidative effect of irradiation treatment on ground beef was overcome.