THE STUDY ON EFFECT OF SODIUM CHLORIDE ON THE ANTIOXIDANT ACTIVITY OF MEET

Meat technological processing has a significant effect on the dynamics and depth of the oxidative processes. The study on the antioxidative activity of the extracts, obtained from the salted meat samples before and after the thermal treatment, was carried out in order to establish a mechanism of action of the main technological processes (meat salting and thermal treatment) on the oxidative changes. The subjects of the research were the samples of pork Longissimus dorsi muscles, which were minced and salted with sodium chloride in the amount of 0.0, 2.0, 3.5 and 5.0%. The antioxidative activity was determined by the rate of oxidation of reduced by oxygen form of 2.6-Dichlorophenolindophenol. The catalase activity was measured spectrophotometrically by the rate of hydrogen peroxide decomposition; the superoxide dismutase activity was measured by the rate of inhibition of the pyrogallol autoxidation; the glutathione peroxidase activity was measured by the rate of NADPH decomposition. The research was carried out at V.M. Gorbatov Federal Research Center for Food Systems of RAS (Russia). According to the study results, meat salting initiated a decrease in the meat antioxidative activity by 9.2-18.0% depending on the sodium chloride concentration. Meat salting with sodium chloride in the amount of 5.0% led to a decrease in the activity of glutathione peroxidase by 24.6%, catalase by 60.1% and superoxide dismutase by 33.7%. The correlation dependence between the antioxidative activity and catalase activities, as well as between superoxide dismutase and glutathione peroxidase activity was revealed: the absolute values of the correlation coefficients were 0.97, 0.99 and 0.94 respectively. In the conducted research a decrease in the meat antioxidative activity by 22.9-28.3% (р < 0.05) was recorded under the action of high temperatures (72 ± 2°С) as a result of catalase inactivation and catalase partial inactivation of superoxide dismutase and glutathione peroxidase. The thermal treatment neutralized the sodium chloride negative effect on the antioxidative activity and activity of the meat antioxidative enzymes (р > 0.05). The obtained results on a decrease in the antioxidative activity in the meat salting process justify the necessity to develop approaches that allow reducing the sodium chloride content in meat products in order to retard the oxidative changes without deterioration of product consumer characteristics