Comparative studies in the effectiveness of antioxidants
Due to their role in preserving the quality and safety of food products having a long shelf life, a study into the effectiveness of food additives with antimicrobial properties appears to be an urgent task. The purpose of the present work is to carry out a comparative assessment of the antioxidant activity of ascorbyl palmitate, alpha-tocopherol, lecithin and dihydroquercetin (taxifolin). Antioxidants were added to a sample of chopped pork fat. After the introduction of the antioxidant, the raw fat was packaged in polymer bags. Then, the sampled raw fat was stored at a temperature of 4±2 °С for 12 days. During the entire shelf life (0, 4, 6, 12 days), studies were conducted to determine the organoleptic characteristics and indicators of hydrolytic (acid number) and oxidative deterioration (peroxide and thiobarbituric number). The organoleptic test on the 6th day revealed the appearance of a yellowish tint in the raw fat admixed with ascorbyl palmitate and lecithin. Moreover, all samples corresponded to the established normalised oxidative deterioration indicator values for the 6-day period. By the end of the storage period (12 days), the samples, with exception of those prepared with the addition of alpha-tocopherol and dihydroquercetin, had a noticeable odour and greenish tinge. Obtained data agreed with the results of physical chemistry studies. Over the period of 6 days of storage, a significant increase was observed in the indices of oxiditative deterioration in all pork fat samples with exception of those admixed with alpha-tocopherol and dihydroquercetin. The most effective action of tocopherol and digidrokvertsetin was applied to the reduction in the accumulation of the second fat oxidation products, which was expressed in a reduction in the thiobarbituric number on the 12th day of storage by 37% and 70%, respectively, in comparison with the control samples. On the basis of the experimental results, it can be concluded that alpha-tocopherol and dihydroquercetin are effective antioxidants for the preservation of animal fat.