Biodiversity from Traditional Bulgarian and French Foods: Microbial and Plant Resources for Innovative Fermentation Processes

Traditional fermented foods and culinary plants constitute complementary microbial and chemical biodiversity resources for food-process innovation. This narrative review critically synthesizes evidence from Bulgarian and French food systems as complementary case studies. It evaluates lactic acid bacteria (LAB) and yeasts from artisanal fermentations together with plant extracts and essential oils for innovative fermentation and biopreservation. Emphasis is placed on strain-level technological performance and safety, plant chemotype and chemical composition standardization, antimicrobial action mechanisms, food-matrix effects, and compatibility between beneficial microorganisms and plant-derived antimicrobials. The central hypothesis is that biodiversity becomes technologically useful when beneficial microorganism and plant extract combinations suppress target spoilage or pathogenic microorganisms while preserving starter culture viability and function and acceptable sensory quality. Evidence is comparatively strong for individual microbial and plant resources but weaker for quantitatively demonstrated synergy, real food validation, storage stability, pilot-scale performance, regulatory feasibility, and economic or environmental benefit. A stage-gated framework is proposed to translate traditional biodiversity into reproducible, safe, and scalable fermented or biopreserved foods.