Deciphering the Microbe–Metabolite Network in Irradiated Chicken Breast Meat: Multi-Omics Characterization of Differential Quality Response Mechanisms to Stepwise Irradiation Doses

In this study, chicken breast samples were exposed to electron beam irradiation at doses of 0, 2, 4, 6, 8, and 10 kGy and analyzed using 16S rRNA sequencing and untargeted metabolomics (LC-MS/MS). The results demonstrated that irradiation significantly altered the diversity of the chicken meat microbiota. <i>Psychrobacter</i> and <i>Chryseobacterium</i> exhibited dose-dependent decreases, whereas <i>Stenotrophomonas</i> and <i>Acinetobacter</i> were identified as irradiation-associated characteristic genera. Functional prediction of these tolerant microbes indicated that growth-related pathways remained active. The irradiation disrupted the metabolic network, resulting in a disordered structure, and the core microbial communities were strongly correlated with amino acid, carbohydrate, alcohol, and lipid metabolism. Partial least squares structural equation modeling indicated that, at low doses (≤4 kGy), irradiation had a significant effect on microbial diversity and metabolite levels, whereas these effects diminished at higher doses. Microbial diversity had no significant effect on meat color or texture, while metabolites were significantly associated with these quality attributes.