Oxidative and hydrolytic stability of alimentary poultry fats under refrigeration and freezing. Issue 11 (29th March 2016) - Pop, Flavia
Abstract : The purpose of this study was to establish the quality of three alimentary poultry fats: goose, duck, and chicken fat, stored under refrigeration (+2°C) and freezing (−18°C). Peroxide value (PV), thiobarbituric acid reactive substances test (TBARS), refractive index value (RIV), iodine value (IV), and saponification value (SV) were determined to measure the degree of oxidative rancidity. Additionally, fatty acid content (FA content) and acidity value (AV) were determined to measure the degree of hydrolytic rancidity. Chemical parameters were significantly influenced by the type of fat, storage time, and storage temperature (except RIV). Samples of fats stored at +2°C maintained acceptable characteristics for 180 days in chicken fat, 210 days in goose fat, and 240 days in duck fat, while acceptability tolerance was found to be 300 days for duck and goose fat and 240 days for chicken fat stored at −18°C. The total content of monounsaturated fatty acids (MUFA) decreased significantly ( p < 0.05) after 300 days of storage at +2°C in chicken fat samples, while the total fatty acid content was not significantly affected by storage temperature in all types of fats. Lipid oxidation in poultry fats varies with the temperature and the length of storage; the lower temperature had a greater retardation effect on rancidity during storage time. Practical applications: Animal fats can be used as an ingredient in meat products or for soap manufacturing. It could also be alternative feedstocks for biodiesel production because their cost is substantially lower than the cost of vegetable oil. The storage of animal poultry fats in proper conditions influences their stability and extends the shelf‐life. Peroxide value, thiobarbituric acid reactive substances test, and acid value were significantly influenced by all treatments: the type of fat, storage temperature, and storage time. In chicken fat was found the highest level of acid value followed by the duck and goose fat. Regardless of the type of fat, the highest level of acid value was found in fat stored at +2°C. Regardless of the type of fat and storage temperature, the highest acid value level was found at 300 days of storage. At both storage temperatures, duck fat was the most stable followed by the goose and chicken fat. Abstract : Peroxide value, thiobarbituric acid reactive substances test, and acid value were significantly influenced by all treatments: the type of fat, storage temperature, and storage time. In chicken fat was found the highest level of acid value followed by the duck and goose fat. Regardless of the type of fat, the highest level of acid value was found in fat stored at +2°C. Regardless of the type of fat and storage temperature, the highest acid value level was found at 300 days of storage. At both storage temperatures, duck fat was the most stable followed by the goose and chicken fat.