Microbiological quality of ready–to–eat vegetables salads served at meat restaurants under the COVID-19 in Turkey

• Alper Baran Atatürk University, Vocational School of Technical Sciences, Department of Food Quality Control and Analysis. Erzurum, Turkey https://orcid.org/0000-0002-3089-6624
• Mehmet Cemal Adigüzel Atatürk University, Faculty of Veterinary Medicine, Department of Microbiology. Erzurum, Turkey https://orcid.org/0000-0002-2385-9649
• Hakan Aydin Atatürk University, Faculty of Veterinary Medicine, Department of Virology. Erzurum, Turkey

DOI: https://doi.org/10.52973/rcfcv-e32171

Keywords: Microbial, ESBL, E. coli, viruses, ready–to–eat salad

Abstract

In Turkish cuisine, ready–to–eat vegetable salads (REVS) served with pide/lahmacun, kebab types, and tantuni from animal source in meat restaurants were evaluated since they have the potential to carry risks in terms of Public Health. The microbiological properties of REVS were investigated using agar plate method. Antimicrobial resistance of foodborne pathogens including Escherichia coli and Staphylococcus aureus was tested using Kirby–Bauer disc diffusion method. Moreover, the presence of important enteric viruses was detected by Polymerase Chain Reaction (PCR). The number of total aerobic bacteria, coliform bacteria, yeast and molds and, Staphylococcus and Micrococcus spp. ranged from less than 1 to 6.40, 1 to 6.26, less than 1–5.82 and less than 1–5.66 log₁₀ colony forming units·grams^-1 (CFU·g^–1) in REVS samples, respectively. None of the REVS tested in this study contained Salmonella spp., whereas E. coli and S. aureus were isolated in 38.1% (16/42) and 2.4% (1/42), respectively. S. aureus was resistant to gentamicin, kanamycin, aztreonam, and ciprofloxacin in the disc diffusion assay, however, it was not harboring the mecA gene. E. coli strains (n=16) were resistant (100%) to aminoglycoside antibiotics and 35.7% (6/16) of the isolates were extended spectrum beta lactamase (ESBL) producing. bla_TEM and bla_CTXM8/25 were detected in two isolates, whereas one isolate carried bla_CTXM–1 and bla_TEM together by PCR. Of the REVS, two were evaluated as positive for rotavirus (4.8%), six for hepatitis A (14%), and hepatitis E virus (14%). These results indicate the high microorganism load, presence of ESBL E. coli, and viral enteric pathogens in REVS, hence it is important to perform routine hygiene practices.

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