Effects of combinatorial hurdles on a non-alcoholic beer matrix challenged with Salmonella Javiana, Escherichia coli, Listeria monocytogenes, Pseudomonas aeruginosa, and Bacillus cereus

Growing consumer interest in reducing alcohol consumption is prompting beverage producers to develop non-alcoholic versions of traditional products; however, the removal of ethanol also removes an important food safety hurdle. This study evaluated whether the remaining intrinsic hurdles of pH (5.0 or 4.2), carbonation (0, 0.75, or 1.5 volumes CO₂), and antimicrobial compounds (none, 10 ppm iso- α -acids, or 100 ppm potassium sorbate) were sufficient to control foodborne pathogens in a non-alcoholic beer matrix. A factorial combination of these variables produced 18 treatments, with 2 additional alternative treatments representing kettle souring and chitosan addition. A five-strain bacterial cocktail containing Salmonella enterica serovar Javiana, Escherichia coli O157: H7 , Listeria monocytogenes 4b, Pseudomonas aeruginosa , and Bacillus cereus (1 × 10^4.8 CFU/mL each) was inoculated into 10.8 oz. of a model non-alcoholic beer and monitored over 60 days. Samples were analyzed in triplicate on days 1, 7, 14, 28, and 60 using selective and differential plating methods. pH was identified as a critical factor for pathogen control, both directly and through the enhancement of other hurdles. Carbonation at 1.50 volumes effectively controlled S. Javiana and E. coli bacteria, whereas reduced carbonation levels supported their growth and survival. Hop acids contributed to additional control of Gram-positive bacteria. Several treatments reduced pathogen populations to below the limit of detection (<10 CFU/mL), corresponding to reductions greater than 3 log units, whereas high-pH treatments lacking additional hurdles supported pathogen growth and survival. These findings demonstrate that recipe design strongly influences the intrinsic antimicrobial stability of non-alcoholic beer and provides practical guidance for producers and process authorities evaluating microbial risk and processing needs in this emerging category.