Year: 2025
Type: article
Abstract: Paucilactobacillus wasatchensis is a nonstarter lactic acid bacteria that has been isolated throughout the United States and is associated with late blowing gas defect (LBD), a continuing problem in the cheese industry, which results in downgraded product and economic loss. While the route of Pa. wasatchensis contamination in milk destined for cheese-making remains inconclusive, the addition of nisin or the application of nisin-producing starter cultures in cheddar production may mitigate LBD by inhibiting Pa. wasatchensis. Nisin sensitivity has not yet been evaluated for Pa. wasatchensis strains. The goal of the current study was to evaluate 8 strains of Pa. wasatchensis for nisin sensitivity using the agar well diffusion method. Nisin inhibition was evaluated across a range of 5 IU/mL to 100 IU/mL. To compare strain sensitivity the lowest nisin concentration that displayed inhibition for all strains was selected (30 IU/mL), and the corresponding inhibition zones were statistically analyzed by an ANOVA with a Tukey-Kramer post-hoc test. The minimum inhibitory concentrations (MIC) for each strain were also estimated. Each Pa. wasatchensis strain showed inhibition within the tested range of nisin concentration. Results from the Tukey-Kramer post-hoc test showed that there were some strain differences in nisin sensitivity, but were not correlated to region of isolation. All strains showed inhibition at 30 IU/mL nisin, which indicates that Pa. wasatchensis is highly sensitive to nisin. This supports addition of nisin, or the application of nisin protective cultures, as a potential effective strategy in mitigating LBD caused by Pa. wasatchensis .
Source: JDS Communications
Authors: Kate Sorensen, Niharika Mishra, Taylor S. Oberg
Institution: Utah State University
Language: English
Subfield: Food Science
Domain: Life Sciences
Open Access status: gold
Estimated APC paid: $1,310
OpenAlex ID: W4415316958