Biofilm formation, antibiotic resistance and genotyping of Shiga toxin-producing Escherichia coli isolated from retail chicken meats.

1. The Shiga toxin-producing Escherichia coli (STEC) is a hazardous zoonotic agent for chicken meat consumers. This study determined the serogroups and evaluated the virulence genes, antibiotic resistance, biofilm-forming profiles and genetic relationships of STEC isolates in chicken meat.2. A total of 100 samples belonging to dressed-whole chicken and different parts of the chicken (wing, breast, thigh, drumstick) were collected between September and November 2019 from different retail markets in Kayseri, Türkiye.3. Phenotypic (identification, disc diffusion test, Congo red agar and microtitre plate tests) and molecular tests (identification, serogrouping, virulence factors, biofilm, antibiotic susceptibility, 16S rRNA sequencing and enterobacterial repetitive intergenic consensus-PCR for typing of the isolates) were carried out.4. E. coli was isolated from 35% of the samples and 35% of the samples harboured at least one STEC. Among 35 STEC isolates, 3 (8.5%), 6 (17.1%), 2 (5.7%) and 3 (8.5%) were found to be positive for fliCH2, fliCH8, fliCH11, fliCH19 genes, respectively. Out of 35 STEC positive isolates, 4 (11.4%) were identified as E. coli O157, from which 2 (5.7%) were E. coli O157:H7. E. coli O157 was detected in two (10%), one (5%), one (5%) of the thigh, drumstick and whole chicken samples, respectively.5. Biofilm-forming ability was reported in 33 (94.2%) of 35 E. coli isolates, whilst the biofilm-associated genes detected among 35 STEC isolates included csgA (88.5%), fimH (88.5%), bcsA (85.7%), agn43 (14.2%) and papC (8.5%). The STEC strains showed resistance against ampicillin (88.5%) and erythromycin (88.5%), followed by tetracycline (74.2%) and gentamicin (25.7%). However, the distribution of isolates harbouring blaCMY, ere(A), tet(A) and aac(3)-IV antibiotic resistance genes was found to be 17.1%, 11.4%, 85.7% and 5.7%, respectively.6. ERIC-PCR showed that E. coli strains obtained from different parts and whole of chicken samples had genetic diversities. ERIC-PCR patterns grouped strains of 35 STEC into eight clusters designated A-H, with 73% similarity. Proper hygiene measures and staff training are essential for public health during poultry processing and in retail stores to control STEC.

Microbiological quality of pastrami and associated surfaces at the point of sale in Kayseri, Turkey.

OBJECTIVE: The aim of this study is to trace the possible relations between the hygienic status of slicing utensils and the microbiological quality of pastrami. STUDY DESIGN: A total of 75 pastrami retail markets were visited in Kayseri, Turkey, where the pastrami (a ready-to-eat meat product) is commonly produced and consumed. Sliced pastrami, the cutting board and knife surface swabs were collected from each pastrami retail point to trace possible sources of contamination. METHODS: Samples were analysed for the presence of total viable counts (TVC), total coliforms, Escherichia coli, members of Enterobacteriaceae, Staphylococcus aureus and Listeria spp. In addition, pastrami samples were analysed for sulphite-reducing Clostridium spp. and Toxoplasma gondii. RESULTS: When compared with the target values of related literatures, a total of 6 (8%) pastrami samples were found unsatisfactory as a result of TVC (5.3%), Enterobacteriaceae (5.3%), E. coli (2.6%), S. aureus (2.6%), Listeria spp. (2.6%) and Listeria monocytogenes (1.3%) contaminations. No T. gondii positivity was observed among the pastrami samples. None of the cutting board and knife surface swabs were found to harbour TVC level >103 cfu/cm2, E. coli and L. monocytogenes. For the total coliforms, 7 (9.3%) and 5 (6.6%) of cutting board and knife surface swabs were found to exceed the target value (<2.5 cfu/cm2), respectively. No statistically significant correlation was detected between the organisms on pastrami and slicing utensils indicating that pastrami were not cross-contaminated by the contact surfaces. CONCLUSION: More emphasis needs to be placed for training of food handlers and to apply good hygienic practices at the point of pastrami sale. The conditions at retail points must be monitored and inspections should be tightened to protect public health.

Detection of Escherichia coli O157:H7 using immunomagnetic separation and mPCR in Turkish foods of animal origin.

UNLABELLED: The present study was conducted to investigate the presence of Escherichia coli O157:H7 in food samples of animal origin and to detect its virulence genes by immunomagnetic separation technique and multiplex PCR (mPCR). A total of 500 samples (consisting of diced meat, minced meat, burger, raw cow's milk and raw cow's milk cheese) were analysed. Escherichia coli O157:H7 was detected in 5 (1%) of 500 analysed samples including two diced meat, one minced meat and two raw-milk cheese. None of the burger samples tested contained E. coli O157:H7. Three isolates obtained from minced and diced meat were found to carry stx1 , stx2 , hlyA and eaeA genes whereas two isolates from raw-milk cheese were found to harbour the stx1 , eaeA and hlyA genes. The results of this study suggest that raw meat and raw-milk cheese tested could pose public health problems in consumers with regard to their virulence factors. SIGNIFICANCE AND IMPACT OF THE STUDY: Escherichia coli (E. coli) O157:H7 is an important human pathogen. Escherichia coli 0157:H7 infections have been associated with consumption of uncooked meat and meat products, as well as unpasteurized dairy products. This study demonstrated that without specific tests for E. coli virulence factors raw meat and raw-milk cheese could pose public health problems to Turkish consumers.

Quality characteristics of doner kebab made from sucuk dough which is a dry fermented Turkish sausage.

The objective of this study was to determine certain quality characteristics of the raw and cooked doner kebabs made from beef and sucuk dough which is a traditional fermented sausage. The doners were divided into two groups; traditional beef doners and sucuk dough groups, and all the samples were frozen and stored at (-30 ±1 °C) for 60 days to monitor their quality characteristics. All of the raw and cooked doner samples were subjected to chemical and microbiological analysis while only the cooked doners were evaluated organoleptically at 0th, 30th and 60th days of storage. In the chemical analysis; proximate composition (% moisture, % protein, % fat, and % ash), pH and TBA values were determined. The samples were examined for total aerobic plate count (APC), total anaerobes, psychrotrophic bacteria, total coliforms, total staphylococcus/micrococcus count, mould and yeast to observe the hygienic quality of the doner samples. The results of chemical analysis, in general, showed that sucuk doners had higher ash content, pH and TBA values, and all of the doners had higher APC, psychrotrophic bacteria and coliform counts at the beginning compared to 30th and 60th days of storage not only in the raw condition but also in cooked counterparts. The sensory evaluation results indicated that sucuk doners received favorable preferences, therefore, traditional sausage (sucuk) dough application in doner production could be possible without posing any acceptability problems in terms of quality factors compared to traditional beef doners.

Effects of liquid smoke on quality characteristics of Turkish standard smoked beef tongue.

The purpose of this research was to determine some quality characteristics of beef tongues processed with liquid and vaporous (traditional) smoke. The tongues were divided into two groups; traditional (vaporous) smoking and liquid smoke application groups, and the processed tongues were vacuum packaged and monitored for quality during 30 days of storage at 4±1 °C. All the smoked tongue samples were subjected to chemical, microbiological and organoleptic analysis at 0, 5, 10, 15 and 30 days of storage. The results indicated that despite some favorable results attributed to traditional smoking, liquid smoke application of beef tongue is also possible without causing any major acceptability problems in terms of quality.