Production and Characterization of Downgraded Maple Syrup-Based Synbiotic Containing Bacillus velezensis FZB42 for Animal Nutrition

The use of antibiotics to promote growth and prevent diarrhea in livestock production has raised concerns about the emergence of antibiotic-resistant bacteria. Probiotics, live microorganisms that confer health benefits, have been proposed as alternatives to antibiotics. In this study, we produced and characterized a downgraded maple syrup-based feed supplement containing Bacillus velezensis FZB42 as a potential synbiotic for animal nutrition. An optimized fermentation medium was developed through a central composite design to produce B. velezensis FZB42 at both the laboratory and pilot scale, reaching a concentration of 6.15 ± 0.46 × 109 CFU/mL. Subsequently, B. velezensis FZB42 was incorporated into a protective whey permeate matrix and spray-dried, resulting in a 31.4% yield with a moisture content of 4.38%. The survival of B. velezensis FZB42 in a simulated gastrointestinal tract was evaluated using the TIM-1 system, revealing a survival rate of 16.05% after passage through the gastric, duodenal, jejunal, and ileal compartments. These findings highlight the possibility of B. velezensis FZB42 being an economically viable and possibly functional synbiotic supplement and effective alternative to antibiotic growth promoters in livestock production.