Antilisterial Properties of Selected Strains from the Autochthonous Microbiota of a Swiss Artisan Soft Smear Cheese

• Published in: Foods 2024-10, Vol.13 (21), p.3473
• Main Authors: Roetschi, Alexandra, Baumeyer, Alexandra, Berthoud, Hélène, Braillard, Lauriane, Gschwend, Florian, Guisolan, Anne, Haldemann, John, Hummerjohann, Jörg, Joller, Charlotte, Loosli, Florian, Meola, Marco, Naskova, Javorka, Oberhänsli, Simone, Shani, Noam, von Ah, Ueli, Arias-Roth, Emmanuelle
• Format: Article
• Language: English
• Subjects: Acetic acid; Aerococcaceae; amplicon sequencing; Bacteria; Carbon sources; Carnobacteriaceae; Cheese; citrate; Dairies; Dairy products; Desemzia; Drinking water; Fermentation; Food contamination & poisoning; Food safety; Foodborne pathogens; Health aspects; Hygiene; inhibition; Lactobacillaceae; Lactose; Leuconostoc mesenteroides; Listeria; Listeria innocua; Listeria monocytogenes; Marinilactibacillus; Microbiota; Microbiota (Symbiotic organisms); Microorganisms; Milk; Organic acids; Pathogens; Ripening; Ruoffia
• ISSN: 2304-8158; 2304-8158
• DOI: 10.3390/foods13213473

High incidences of the foodborne pathogen have been reported on smear cheeses, and despite increased hygiene efforts, this incidence has remained stable in recent years. Applying antilisterial strains may increase the safety of smear cheeses. To find and test antilisterial strains, we inoculated fresh soft cheeses from nine dairies with the surrogate species and assessed its growth under standardized ripening conditions. Acetic acid at day 23 (r = -0.66), lactose in fresh cheese (r = -0.63), and glucose at day 10 (r = -0.62), as well as seven amplicon sequence variants (ASVs), were negatively correlated with growth. Two of these ASVs were assigned to the genus of Lactobacillaceae (r = -0.82 and -0.71). Isolates from this family, from Aerococcaceae, and Carnobacteriaceae were characterized according to their inhibitory properties, and those showing antilisterial properties were applied as protective cultures in challenge tests. The combined application of strains of , Aerococcaceae, and Carnobacteriaceae successfully eliminated low levels of in the final products. This is likely explained by antimicrobial compounds, including mesentericin Y105 and acetate, and competition for carbon sources and iron. This study shows a promising way to improve the safety of soft smear cheeses by applying defined protective cultures.