Study on Microbial Growth Model and Shelf-Life of Shao-Mai during Electron Beam Irradiation

Abstract:

To address the issue of short shelf life due to microbial proliferation in the industrialized production of a traditional food Shao-Mai, the pre-made and unsteamed Shao-Mai was treated with electron beam irradiation at different doses. The growth patterns of microorganisms and changes in peroxide values in irradiated Shao-Mai under different storage temperatures were studied. The results showed that electron beam irradiation effectively reduced the microbial count in Shao-Mai and prolonged the shelf life. However, higher doses of irradiation promoted lipid oxidation. Irradiation doses of 6~8 kGy irradiation showed no promoting effect on lipid oxidation, and the irradiated Shao-Mai exhibited no significant difference in peroxide value compared to non-irradiated products (P>0.05) after 3 days of storage at 30 ℃. When refrigerated at 4 ℃, Shao-Mai irradiated at dose of 6~8 kGy had a shelf life of up to 30 days, which was 20 days longer compared to non-irradiated products. According to the changes of total bacterial count and moulds and yeasts under different storage temperatures, the corresponding Gompertz microbial growth models were established respectively. The correlation coefficients of the models were all greater than 0.95, effectively describing the dynamic changes in microbial growth of irradiated Shao-Mai during storage and predicting the microbial level over different storage times.