Screening of Antifungal Lactic Acid Bacteria and Their Impact on the Quality and Shelf Life of Rye Bran Sourdough Bread

In the present study, <i>Lactiplantibacillus plantarum</i> G8, exhibiting higher antifungal activity, and G12, displaying weaker antifungal activity, were isolated from naturally fermented wheat sourdough. Their impacts on bread quality and shelf life were subsequently investigated. The results demonstrated that both strains exhibited robust growth in rye bran sourdough. Compared to the blank control rye bran-wheat flour dough (RB dough), sourdough incorporation enhanced percentages of β-sheet and α-helix secondary structures, facilitating the formation of a more ordered gluten network structure. This contributed to reduced bread baking loss and decreased bread hardness, gumminess, and chewiness, with <i>Lpb. plantarum</i> G8 exhibiting the most pronounced effects. Notably, G8 bread displayed superior antifungal efficacy, extending shelf life by 8 d (mold appearance at room temperature: 12 d for G8 vs. 4 d for RB). Furthermore, G8 bread exhibited significantly increased diversity and content of volatile compounds, and received higher preference scores from the sensory panel. This study further advances the development of mold-resistant bakery products.