关键词: 卤蛋；杀菌温度；贮藏期；脂肪酸组成；微生物

Abstract: In order to study the changes in the total bacterial count and fatty acid composition of marinated eggs as a function of sterilization temperature and storage temperature, vacuum-packed marinated eggs were sterilized at 95, 105 or 121 ℃, and stored at 4 or 25 ℃ (those sterilized at 121 ℃ were stored exclusively at 25 ℃). The results showed that sterilization at each temperature could effectively kill bacteria, and the total bacterial count in each group was less than 10 CFU/g. The contents of polyunsaturated fatty acids (PUFA) in the samples sterilized at 105 and 121 ℃ decreased by 1.56% and 6.83%, respectively, compared with that sterilized at 95 ℃. Different changes in fatty acid composition as a function of storage time were found among groups, depending on such factors as sterilization temperature, storage temperature, microbial species, microbial proliferation and oxidative hydrolysis reaction. The samples sterilized at 95 ℃ could be stored at 25 ℃ for only 15 days and had the fastest rate of deterioration of fatty acids. The samples sterilized at 105 ℃ could be stored at 25 ℃ for 75 days, and had a slow rate of deterioration of fatty acids. The samples sterilized at 95 ℃ could be stored at 4 ℃ for 90 days, but the rate of deterioration of fatty acids was faster. Microbial proliferation was not detected in the samples subjected to sterilization at 121 ℃ after 90 days of storage at 25 ℃. During storage, fatty acids were retained well, but the initial level of polyunsaturated fatty acids was low. Microbial proliferation was not detected in the samples sterilized at 105 ℃ after 90 days of storage at 4 ℃, either, and the retention rate of fatty acids was the highest during storage. Accordingly, sterilization at 105 ℃ and stored at 4 ℃ can be used for the production of marinated eggs with high nutrient level and long shelf life.

Key words: marinated eggs; sterilization temperature; storing period; fatty acids; microbes