Effect of electron beam irradiation on microbial inactivation, nutritional and quality properties of semi-moist pet foods

Abstract

The objective of this study was to evaluate the effect of electron beam irradiation (E-beam) on semi-moist pet foods at different absorbed doses. The samples were exposed to e-beam at dose levels of 0, 2.5, 5, and 10 kGy. Then, their effect on microbiological, nutritional, and physicochemical properties was analyzed during 60 days of storage. A dose-dependent effect was observed in bacterial pathogens, especially, 10 kGy sterilized them without further growth throughout the storage period. The nutrient analysis confirmed that 10 kGy of e-beam irradiation did not significantly influence the nutritional components of semi-moist pet foods, ensuring they are nutritionally safe for pets. Irradiated samples showed less changes in quality over time, with lower microbial growth and stable attributes like water activity, pH, and redness (a*). While samples treated with 10 kGy initially showed more lipid oxidation and protein degradation, these differences were not significant by day 60, suggesting that higher doses did not affect physicochemical properties during storage. In contrast, non-irradiated samples

experienced microbial and physicochemical changes over the extended storage. Therefore, we conclude that e- beam irradiation up to 10 kGy can secure microbial safety in semi-moist pet foods, preserving their nutritional

and quality attributes for pets’ consumption.