Gan_2025_Int.J.Food.Microbiol_437_111220

This study investigated the impact of L. paracasei C5 on the generation of flavor compounds in bread through metagenomics and flavouromics. Metagenomic profiling revealed that L. paracasei C5 facilitated carbohydrate, amino acid, and lipid metabolism in the dough. Correlative analyses between specific microbial species and flavor compounds demonstrated a positive association between L. paracasei and key flavor compounds in bread, such as 2-nonenal,(E)-, 2-octenal,(E)-, benzeneacetaldehyde, and hexanoic acid, ethyl ester. A predictive network outlining the metabolic pathways responsible for L. paracasei C5 sourdough bread flavor compounds was established, elucidating the microbial annotation of pertinent genes and enzymes. The findings underscored the synergistic role of L. paracasei and S. cerevisiae in enhancing the activity of encoded enzymes involved in carbohydrate degradation, acetyl-CoA synthesis, succinate conversion, acyl-CoA production, transaminases, alcohol dehydrogenase, and carboxylesterases. These results offer novel insights into the mechanisms by which L. paracasei C5 augments bread flavor.