The objective of this study is to measure the amounts of biogenic amines, microbial counts, values of pH, titratable acidity, dry matter, and salt (%) in herby cheese, a very popular staple in the Turkish diet, and to evaluate the concentration of biogenic amines in terms of public health risks. A high-performance liquid chromatography (HPLC) method was used for the determination of eight biogenic amines in 100 herby cheeses sold in the local markets of Van. The bacterial load of the herby cheeses ranged between 4.0 and 8.90 log CFU/g for viable total aerobic mesophilic bacteria (TAMB), <1 and 7.0 log CFU/g for lactic bacteria (LAB), <1 and 6.08 log CFU/g for coliform bacteria, <1 and 5.81 log CFU/g for Enterobacteriaceae, <1 and 2.60 log CFU/g for Staphylococcus aureus, and 3.70 and 8.05 log CFU/g for yeasts and molds. The results obtained suggested significant changes in the pH, titratable acidity, dry matter, and salt contents of the examined herby cheese samples. The detection levels of biogenic amines in the samples ranged from <0.025 to 33.36 mg/kg for tryptamine, from <0.038 to 404.57 mg/kg for β-phenylethylamine, from 0.03 to 426.35 mg/kg for putrescine, from <0.039 to 1438.22 mg/kg for cadaverine, from <0.033 to 469 mg/kg for histamine, from <0.309 to 725.21 mg/kg for tyramine, from <0.114 to 1.70 mg/kg for spermidine, and from <0.109 to 1.88 mg/kg for spermine. As a result, these cheeses are fit for consumption in terms of the amounts of biogenic amines they contain.

The Shiga toxin-producing Escherichia coli (STEC) strains are currently considered important emerging pathogens threatening public health. Among Shiga toxin-producing Escherichia coli, E. coli O157:H7 strains have emerged as important human pathogens. This study was conducted to determine the presence of Escherichia coli O157 and O157:H7 in raw milk samples and Van herby cheese samples. For this purpose, 100 samples of raw milk were collected and 100 samples of herby cheese sold for consumption in Van province in Turkey were obtained from grocers and markets in order to detect the presence of Escherichia coli O157 and O157:H7. The method of E. coli O157 and O157:H7 isolation proposed by the Food and Drug Administration (FDA) was used. E. coli O157 in raw milk and herby cheese samples was found in 11% and 6% of samples respectively, and E. coli O157:H7 was found in 2% of herby cheese samples. No E. coli O157:H7 was detected in raw milk samples. This study showed that raw milk was contaminated with E. coli O157 and herby cheese was contaminated with both E. coli O157 and E. coli O157:H7; therefore, herby cheese poses a serious risk to public health.

This study was conducted to detect contamination level of Listeria species in ready-made meatballs kinds that are stored under frozen or cooled conditions. In isolations and identifications of Listeria species from the samples, method approved and suggested by USDA/FSIS (United States Department of Agriculture/Food Safety and Inspection Service) was used. The strains that were identified to be Listeria monocytogenes with biochemical tests was verified as species through Real Time PCR method by using a primary pair specific to hly A gene location. In this study, a total number of 290 different type ready-made meatball samples were analysed. As a result of examining all samples was isolated L. monocytogenes in 32 (11.04%) samples, L. ivanovii in 9 (3.10%) samples, L. innocua in 22 (7.59%) samples, L. welchimerii in 8 (2.76%) samples and also L. seeligeri in 4 (1.38%) samples. In the serotyping of the 32 L. monocytogenes strains isolated from the samples; 15 isolated are found to be Type 1, where 3 strains are found to be Type 4, 11 strains to be type Poly and the rest 3 strains could not typified. The Mean pH and water activity values for the samples were found to be 6.62±0.56 and 0.985±0.007 respectively. In the result of the study, identifying Listeria species especially L. monocytogenes in cooled and frozen ready-made meatball samples studied suggest that such products whose consumption increased in the recent years pose important risk in terms of public health.

No abstract

ÖzBu araştırma, Bitlis'in Tatvan ilçesinde farklı lokanta ve işletmelerde pişirilmiş olarak tüketime sunulan tavuk dönerlerin mikrobiyolojik ve fiziko-kimyasal kalitesini tespit etmek amacıyla yapılmıştır. Bu amaçla 50 adet tavuk döner numunesi incelenmiştir. Numunelerin mikrobiyolojik analizleri sonucunda ortalama toplam aerob mezofilik mikroorganizma (TAMM), koliform grubu mikroorganizma, Escherichia coli, Staphylococcus aureus, koagulaz (+) S. aureus, laktobasiller, Enterobacteriaceae grubu mikroorganizma, Pseudomonas spp. ile maya-küf sayıları sırasıyla 4.86±0.94 log10 kob/g, 2.34±1.17 log10 kob/g, 2.84±0.85 log10 kob/g, 4.00±1.04 log10 kob/g, 3.79±1.23 log10 kob/g, 3.70±1.41 log10 kob/g, 2.64±1.04 log10 kob/g, 3.19±0.63 log10 kob/g ve 2.39±1.02 log10 kob/g olarak belirlenmiştir. İncelenen numunelerde Salmonella spp. ve sülfit indirgeyen anaerob mikroorganizmalara rastlanmamıştır. Fiziko-kimyasal analizler sonucunda da numunelerdeki ortalama pH ve su aktivitesi (aw) değerleri sırasıyla 6.12±0.20 ve 0.985±0.01 olarak tespit edilmiştir. İncelenen numunelerin sadece Salmonella spp. yönünden standartlarda belirtilen kriterlere uygun olduğu görülmüştür. Bununla birlikte, mikrobiyolojik özellikler yönünden pişirilmiş haldeki tavuk dönerlerin bazı mikroorganizmalar yönünden hijyenik kalitesinin iyi olmadığı, ayrıca incelenen numunelerin %8'inin E. coli ve %22'sinin de S. aureus yönünden standartlara uygun olmadığı tespit edilmiştir. Sonuç olarak; üretimde kaliteli hammadde kullanıldığında, etkin ve yeterli pişirme işlemleri uygulandığında, üretim/servis sırasında hijyenik kurallara gerekli özen gösterildiğinde ve personeller hijyen konusunda yeterli bilgiye sahip olduklarında halk sağlığı açısından risk oluşturmayacak daha kaliteli ürünlerin elde edilmesi mümkün olacaktır.

Türkiye’de Van ili piyasasından toplanan tavuk eti örneklerinde Enterococcus spp. prevelansı ve antibiyotik direnliliği ve VanA ve VanB direnç genlerinin belirlenmesi amaçlandı. Çalışmada 100 adet tavuk eti örneği kullanıldı. Bunların 27’si (%27) Enterococcus spp. pozitif bulundu. 27 pozitif tavuk eti örneğinden toplam 67 adet Enterococcus spp. izolatı elde edildi. Bunlardan 53’ü (%79.10) E. faecalis, 14’ü (%20.90) ise E. faecium olarak tespit edildi. Antibiyotik dirençlilikleri incelenen Analizler sonucunda Enterococcus spp. izolatlarının 27’sinin (%40.30) iki veya daha fazla antibiyotiğe dirençli olduğu, 25’inin (%37.31) ise en az bir antibiyotiğe dirençli veya orta düzeyde olduğu tespit edilmiştir. E. faecalis ve E. faecium suşlarının en az %50’si ampisilin, penisin, kloramfenol, vankomisin ve gentamisine duyarlı ve orta düzeyde olduğu tespit edildi. Ayrıca fenotipik olarak vankomisine dirençli ve orta düzeyde olan 13 izolatta VanA ve VanB geni varlığı araştırıldı. PCR testi ile analizi yapılan izolatların hiçbirinde VanA ve VanB geni tespit edilemedi. Sonuç olarak, tavuk etlerinde Enterococcus spp. tespit edilmesi hijyenik koşullara dikkat edilmediğinin göstergesidir. Aynı zamanda bu gıdalardan elde edilen izolatlarda çoklu antibiyotik dirençliliğinin var olması ayrıca fenotipik olarak belirlenen dirençliliklerin halk sağlığını tehdit edebileceğini düşündürmektedir.

It has been identified that total number of aerobic mesophilic microorganisms (TAM), total number of aerobic psychrophilic microorganisms (TAP), number of Pseudomonas spp. (PS), number of yeast and molds (Y/M), number of microorganisms in coliform group (CG), number of fecal streptococci (FS), number of microorganisms in Enterobacteriaceae group (EB) and number of microorganisms Lactobacillus-Leuconostoc-Pediococcus group (LB) and values of pH, quantities of total volatile basic nitrogen (TVB-N) have been determined, data of sensory analysis has been evaluated by hedonic scale of whole and gutted specimens of carp (Cyprinus carpio L., 1758) which were whole and gutted frozen kept under-18 ºC at 1 st , 15 th , 30 th , 60 th , 90 th , 120 th days and biogenic amines tryptamine (TRM), β-phenylethylamine (PEA), putrescine (PUT), cadaverine (CAD), histamine (HIM), tyramine (TYM), spermidine (SPD) and spermine (SPM) were assayed by High Performance Liquid Chromatography (HPLC) method. According to the results of the research: In Frozen Whole Fish (FWF) and Frozen Gutted Fish (FGF) samples, psychrophilic microorganisms constitute the dominant microorganism group, the mean pH values of FWF and FGF samples were 6.53±0.12 and 6.63±0.11, and TVB-N values were 13.38±1.39 and 12.87±0.81 respectively, the samples were found to be in "good" quality class in terms of sensory evaluations. It was determined that all biogenic amines remained below the recommended limit values during the whole storage period, according to the changes in chemical and sensory properties, that these fish preserved their consumable properties.

In the research conducted; Microbial load, chemical parameters and sensory analysis scores and by determining the concentrations of biogenic amine of whole (Cold Whole Fish/CWF) and cleaned (Cold Gutted Fish/CGF) carp samples (Cyprinus carpio L., 1758) stored at 4 °C for 14 days, was aimed to determine the shelf life. 0th, 2nd, 4th, 6th, 8th, 10th, 12th, and 14th on days of storage microbiological analyzes (Total Aerobic Mesophilic Microorganism (TAM), Total Aerobic Psychrophilic Microorganism (TAP), Pseudomonas spp. (PS), Yeast/Mold (Y/M), Coliform microorganism (CG), Fecal Streptococcus (FS), Enterobactericeae group microorganism (EB) and Lactobacillus-Leuconostoc-Pediococcus group microorganism (LB) counts), chemical (pH and Total Volatile Basic Nitrogen (TVB-N)), sensory analysis evaluation and biogenic amine (tryptamine (TRM), β-phenylethylamine (PEA), putrescine (PUT), cadaverine (CAD), histamine (HIM), tyramine (TYM), spermidine (SPD) and spermine (SPM)) levels detected by using High Performance Liquid Chromatography (HPLC). According to the research results; It was determined that TAP and Pseudomonas spp. formed the dominant flora during storage in CWF and CGF samples, the recommended limit values were not exceeded until the 10th day in terms of TVB-N, and according to the sensory analysis evaluations, they were not consumable after the 6th day. It was determined that putrescine and cadaverine were dominant biogenic amines in both application forms of the samples stored in the cold. Although there is no significant microbiological difference between the preservation of whole and gutted fish samples, it has been determined that keeping the carp whole is safer than keeping it after gutted, based on the microbiological values of the 8th day when the samples were rejected sensory. In addition, it is thought that putrescine and cadaverine can be evaluated as indicator biogenic amines in determining the freshness of carp fish.