Influence of drying conditions, food composition, and water activity on the thermal resistance of Salmonella enterica

• Published in: Food research international 2021-09, Vol.147, p.110548-110548, Article 110548
• Main Authors: Dhaliwal, Harleen Kaur, Gänzle, Michael, Roopesh, M.S.
• Format: Article
• Language: English
• Subjects: Adsorption isotherm; Low-water activity products; Salmonella enterica; Thermal resistance; Water activity; Weibull model
• ISSN: 0963-9969; 1873-7145
• DOI: 10.1016/j.foodres.2021.110548

Graphical illustration of the inoculation methods of (A) wet and, (B) dry transfer of bacteria in the low-aw foods (Created with BioRender.com). [Display omitted] •Screening of Salmonella strains based on the relative resistance is important.•Thermal resistance of Salmonella varies due to the complexity of the food matrix.•Differences in serovars and aw impact desiccation and thermal tolerance.•Differences in the inoculation methods influence Salmonella's thermal resistance. Salmonella contamination of low-water activity (aw) foods poses a serious concern worldwide. The present study was conducted to assess the effects of drying conditions, food composition, and water activity on the desiccation tolerance and thermal resistance of S. Enteritidis FUA1946, S. Senftenberg ATCC43845 and S. Typhimurium ATCC13311 in pet food, binder formulation, and skim milk powder. The samples were wet inoculated with the individual Salmonella strains and were equilibrated to aw 0.33 and 0.75, followed by an isothermal treatment at 70 °C. The thermal inactivation data was fitted to the Weibull model. Irrespective of the aw, food composition and physical structure of the selected foods, strain S. Enteritidis FUA1946 displayed the highest desiccation and thermal resistance, followed by S. Senftenberg ATCC43845 and S. Typhimurium ATCC13311. The food matrix and strain type significantly (p