Fermentation Characteristics of Biofilm-forming Lactic Acid Bacteria in Sausages

Abstract:

[Objective] To address the challenge of controlling harmful bacteria during the fermentation process of sausages, this study optimized the biofilm formation conditions of Lactiplantibacillus plantarum (L. plantarum) JB1 to enhance its competitive advantage in the low-temperature fermentation environment of sausages. Furthermore, this study systematically evaluated the regulatory role of the biofilm-forming L. plantarum JB1 in the quality and safety of sausages, aiming to provide process parameters and a theoretical basis for the development of high-stability probiotic formulations. [Method]Single-factor and orthogonal experiments were conducted to quantify the effects of the interactions between temperature, pH, carbon source, nitrogen source, metal ions, and buffer salts on the biofilm-forming L. plantarum JB1. A sausage fermentation model was employed to evaluate the effects of free-cell and biofilm-forming L. plantarum JB1 on microbial communities, biogenic amines, free protein hydrolysis, and sensory indicators of sausages. [Result] The optimal conditions for the biofilm formation of L. plantarum JB1 were a temperature of 37 ℃ and pH 6.5. The optimal culture medium was composed of 35 g/L maltose, 5 g/L peptone, 0.2 g/L Mn²⁺, and mass fraction 1.0% K₂HPO₄. Under these conditions, the biofilm formation of L. plantarum JB1 increased by 43.9% compared with that in the control group using the original MRS medium (P<0.05). In the 4 d fermentation of sausages, compared with the free-cell L. plantarum JB1, the biofilm-forming L. plantarum JB1 increased the lactic acid mass fraction by 8.5%, reduced the Enterobacteriaceae count by 16.5%, and decreased the total biogenic amine mass fraction by 7.7%. Moreover, it enhanced protein hydrolysis, resulting in increased mass fractions of small peptides and free amino nitrogen. In addition, the biofilm-forming L. plantarum JB1 increased the redness and decreased the lightness and yellowness of sausages. [Conclusion] Multi-factor synergistic regulation is key to the biofilm formation of L.plantarum JB1. Biofilm technology can specifically address safety risks during the fermentation stage, providing a new solution for the development of functional fermented meat products.