Investigating desiccation resistance, post-rehydration growth, and heat tolerance in desiccation-injured cells of Salmonella enterica isolated from the soybean production chain

Marianna M Furtado; Beatriz S Silva; Luísa Freire; Juliana S Graça; Verônica O Alvarenga; Humberto M Hungaro; Anderson S Sant'Ana

doi:10.1016/j.ijfoodmicro.2023.110387

Investigating desiccation resistance, post-rehydration growth, and heat tolerance in desiccation-injured cells of Salmonella enterica isolated from the soybean production chain

Int J Food Microbiol. 2023 Nov 16:405:110387. doi: 10.1016/j.ijfoodmicro.2023.110387. Epub 2023 Sep 1.

Authors

Marianna M Furtado¹, Beatriz S Silva¹, Luísa Freire¹, Juliana S Graça¹, Verônica O Alvarenga², Humberto M Hungaro³, Anderson S Sant'Ana⁴

Affiliations

¹ Department of Food Science and Nutrition, Faculty of Food Engineering, University of Campinas, Campinas, SP, Brazil.
² Department of Food Science and Nutrition, Faculty of Food Engineering, University of Campinas, Campinas, SP, Brazil; Department of Food, Faculty of Pharmacy, Federal University of Minas Gerais, Belo Horizonte, MG, Brazil.
³ Department of Pharmaceutical Sciences, Faculty of Pharmacy, Federal University of Juiz de Fora, Juiz de Fora, MG, Brazil.
⁴ Department of Food Science and Nutrition, Faculty of Food Engineering, University of Campinas, Campinas, SP, Brazil. Electronic address: and@unicamp.br.

PMID: 37672943
DOI: 10.1016/j.ijfoodmicro.2023.110387

Abstract

This study compared the resistance to different desiccation conditions of 190 Salmonella enterica strains previously isolated from the soybean meal production chain and belonging to 23 serovars. Additionally, the post-rehydration growth and heat tolerance of the strains previously exposed to desiccation were determined. Variability in desiccation resistance was observed both within and between serovars. Strains belonging to S. Havana and S. Schwarzengrund serovars were the most resistant, regardless of storage condition. The drying temperature (20 °C and 30 °C) did not influence the desiccation resistance of the Salmonella strains. On the other hand, increasing drying time from 1 to 7 days reduced Salmonella counts. The origin (isolation sources) also influenced the desiccation resistance of the Salmonella strains. The growth of the Salmonella strains after rehydration varied considerably depending on the drying conditions and incubation temperature during cultivation. An increase in the time and temperature of drying led to a reduction in population of most Salmonella strains after rehydration. Salmonella strains previously desiccated also showed differences in the heat tolerance in all temperature-time binomials tested. Some strains were highly resistant to heat tolerance conditions, presenting <1 log CFU/mL reduction from the initial population. The results obtained in this study suggest that the strategies to mitigate Salmonella in low-a_w foods must consider the existence of high-stress resistant strains and their multiple-stress adaptability profiles, including effects of processing, food composition, and storage conditions.

Keywords: Drying; Low water activity foods; Recovery; Stress; Thermal resistance; Variability.

MeSH terms

Desiccation
Fluid Therapy
Glycine max
Salmonella enterica*
Thermotolerance*