Microbiological safety and antimicrobial resistance in cashew-based plant-based cheese analogues
TL;DR
It is suggested that microorganisms associated with plant-based cheese analogues may act as reservoirs of antimicrobial resistance determinants, highlighting the importance of safety assessment and microbiological surveillance of strains intended for technological or probiotic applications.
Abstract
The demand for plant-based cheese analogues has increased in recent years, driven both by the growing adoption of vegan and vegetarian diets and by consumers seeking plant-based alternatives to animal-derived products. Their production relies on diverse raw materials and often incorporates fermentation processes involving molds, yeasts, and lactic acid bacteria (LAB). Within this context, ensuring food safety, including the antimicrobial resistance (AMR) aspects, is essential due to the complex microbial communities involved in fermentation. Therefore, this study investigated the presence of bacterial species of potential public health relevance and assessed AMR profiles and genes in plant-based cheese analogues acquired in Brazil. None of the samples tested positive for Salmonella spp., coagulase-positive Staphylococcus, or Escherichia coli, while Bacillus cereus was detected in one sample. Two atypical colonies recovered on selective media for Salmonella were identified as Cronobacter malonaticus and Delftia acidovorans. Most samples exhibited high mold and yeast counts, likely associated with fermentation and maturation processes. Among 176 LAB isolates, 11 species were identified by MALDI-TOF, and twenty representative strains were selected for antimicrobial susceptibility testing. Resistance was detected in a limited number of isolates, mainly to ciprofloxacin, tetracycline, and gentamicin, whereas C. malonaticus exhibited resistance to penicillin. Whole-genome sequencing was performed on Lactiplantibacillus plantarum, Levilactobacillus brevis, Leuconostoc mesenteroides, Enterococcus faecium, and C. malonaticus. A total of eight antimicrobial resistance genes were identified, four of which were located on plasmids in C. malonaticus and L. brevis. These findings suggest that microorganisms associated with plant-based cheese analogues may act as reservoirs of antimicrobial resistance determinants, highlighting the importance of safety assessment and microbiological surveillance of strains intended for technological or probiotic applications.