Heat-resistance of suspect persistent strains of Escherichia coli from cheesemaking plants

Irena Němečková, Šárka Havlíková, Tereza Gelbíčová, Lucie Pospíšilová, Eliška Hromádková, Jana Lindauerová, Alžběta Baráková and Renáta Karpíšková
Additional contact information
Irena Němečková: Dairy Research Institute, Prague, Czech Republic
Šárka Havlíková: Dairy Research Institute, Prague, Czech Republic
Tereza Gelbíčová: Veterinary Research Institute, Brno, Czech Republic
Lucie Pospíšilová: Veterinary Research Institute, Brno, Czech Republic
Eliška Hromádková: Dairy Research Institute, Prague, Czech Republic
Jana Lindauerová: Dairy Research Institute, Prague, Czech Republic
Alžběta Baráková: Veterinary Research Institute, Brno, Czech Republic
Renáta Karpíšková: Veterinary Research Institute, Brno, Czech Republic

Czech Journal of Food Sciences, 2020, vol. 38, issue 5, 323-329

Abstract: Besides its health and spoilage hazards, Escherichia coli is a process hygiene indicator for cheeses made from milk that has undergone heat treatment. Hence, its ability to persist in cheesemaking plant environment and equipment is important. In total, 120 samples from two producing plants were analysed and 72 E. coli isolates were obtained. The target was to find out whether there is a difference in heat-resistance between persistent and non-persistent E. coli strains. The strains were selected using macrorestriction analysis and recurrent detection in cheesemaking plants hereby: one strain persisting in brine for blue-veined cheeses, two strains persisting in brine for hard cheeses and one non-persistent strain from raw material. Their D(50)-values were 196; 417; 370 and 182 min, respectively, D(59)-values ranged from 20 to 32 min and z-values were 7.5; 6.6; 8.1 and 9.0 °C, respectively. The non-persistent strain was the least resistant to heating to 50 °C but it was not the least resistant generally. All tested strains were highly heat-resistant and carried genes of the heat resistance locus LHR1 and/or LHR2. Our results emphasise the need to screen for the presence of LHR genes and the occurrence of heat-resistant E. coli in cheese production where they could survive sub-pasteurisation temperatures and contaminate the manufacturing environment and finished products.

Keywords: brine; cheese; hygiene indicator; locus of heat resistance; persistence (search for similar items in EconPapers)
Date: 2020
References: View complete reference list from CitEc
Citations:

Downloads: (external link)
http://cjfs.agriculturejournals.cz/doi/10.17221/193/2020-CJFS.html (text/html)
http://cjfs.agriculturejournals.cz/doi/10.17221/193/2020-CJFS.pdf (application/pdf)
free of charge

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:caa:jnlcjf:v:38:y:2020:i:5:id:193-2020-cjfs

DOI: 10.17221/193/2020-CJFS

Access Statistics for this article

Czech Journal of Food Sciences is currently edited by Ing. Zdeňka Náglová, Ph.D.

More articles in Czech Journal of Food Sciences from Czech Academy of Agricultural Sciences
Bibliographic data for series maintained by Ivo Andrle ().