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This study examined the effect of lemon juice on sensory, biochemical and microbiological quality of sous vide (SV)-packaged bonito. Bonitos were salted (0.2%) and divided into two groups. The first group (SV) was vacuum-packaged in a gas barrier plastic pouch, pasteurised (70°C, 10 min) and stored at 4 ± 1°C. The second group [(lemon juice-treated sous vide (LSV)] was treated with lemon juice, vacuum-packaged, pasteurised and stored similarly. LSV samples had lower pH, mesophilic and psychrophilic aerobic counts than SV samples (P < 0.05), and they had better sensory quality. SV samples spoiled on the 35th day, while the LSV samples were acceptable until 49th day of storage. This result shows that treatment with lemon juice increased the acceptability and shelf life of SV packaged bonito for 2 weeks (40%). When compared to several other mild preservation procedures, addition of lemon juice to SV fish is inexpensive and uncomplicated method.

The effect of storage temperature on the shelf life of sous vide packaged (70C, 10 min) whiting was determined. Samples stored at 12 ± 1C spoiled according to sensory test on the 21st day, when mesophilic aerobic bacteria and trimethylamine nitrogen (TMA‐N) exceeded the limits. However, their consumption is not advisable after 15 days because psychrophilic counts exceeded the recommended limits at that day. In cold storage (4 ± 1C) Total volatile basic nitrogen and TMA‐N, values of the samples exceeded the limits on the 42nd day. However, because samples spoiled according to sensory test, and mesophilic and psychrophilic aerobic bacterial counts were above the limits, shelf life was considered as 35 days. Sous vide cooking at 70C for 10 min could extend significantly the shelf life of whiting both at 4C and temperature‐abuse conditions (12C). PRACTICAL APPLICATIONS Sous vide is a long established but relatively little‐known cooking process. The data regarding the effect of storage temperature on the shelf life and quality of sous vide fish are very limited. Therefore, this study aimed to determine the sensory, microbiological and chemical quality of sous vide packaged whiting during refrigerated storage (4 ± 1C) and temperature‐abuse temperature conditions (12 ± 1C). The results of this study can be utilized by researchers in future studies as well as by manufacturers to determine the processing and storage conditions of sous vide fish.

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The aim of this study was to determine the quality and shelf life of sous vide bonito stored at 4 and 12C. The total volatile basic nitrogen (TVB‐N) values of cold stored samples exceeded the recommended limit on 35th day of storage, while they were unacceptable according to sensory scores. The TVB‐N and trimethylamine‐N values of sous vide samples stored at 12C exceeded the limits at the 18th day, while sensory scores were very close to the acceptability limit. For all samples, mesophilic and psychrophilic bacterial counts exceeded the limits after they were regarded as spoiled. Therefore, the shelf life of the sous vide bonito, cooked at 70C for 10 min, was 28 days at 4C while 15 days at 12C. It was seen that sous vide packaging provided a long shelf life for bonito. PRACTICAL APPLICATIONS Sous vide is a long established but relatively little known cooking process. The data regarding the effect of storage temperature on shelf life and quality of sous vide fish are very limited. Therefore, this study aimed to determine the sensory, microbiological and chemical quality of sous vides packaged bonito during refrigerated storage (4 ± 1C) and abuse temperature conditions (12 ± 1C). The results of this study can be utilized by researchers in future studies as well as by manufacturers to determine the processing and storage conditions of sous vide fish.

This study aimed to determine the antibiotic and bacteriocin sensitivity of <i>Listeria monocytogenes</i> strains isolated from animal derived foods. With disc diffusion assay, all fourteen L. <i>monocytogenes</i> strains were suscepti-ble to the antibiotics, including penicillin G, vancomycin, tetracycline, chloramphenicol, rifampicin, erythromycin, gentamicin and trime- thoprim. However, the percentages of fosfomycin and streptomycin resistances were 92.9% and 7.1%, respectively. Multiple resistances were not observed among the tested strains. The results of well diffusion assays showed that all strains were inhibited by the cell-free supernatant of a bacteriocin-producing strain, <i>Pediococcus acidilactici</i> 13, with the inhibition zones ranging from 16.00 to 24.50 mm. These results provide useful information on antibiotic resistance of L. <i>monocytogenes</i> strains isolated from foods, and can potentially be used to develop bacteriocin-based interventions to guard against the hazards associated with L. <i> monocytogenes</i> in ready-to-eat meat and poultry products

Chicken leg and breast meat samples were inoculated with Campylobacter jejuni (ATCC 33291) at a level of 4–5 log most probable number/cm2 and dipped in lactic acid (LA; 1 and 3%) and acetic acid (AA; 1 and 2%) solutions for 10 min. Control samples were dipped in tap water. Samples were packed in polystyrene trays covered by stretch film and stored at 4C for 10 days and at−18C for 6 months. Immediately after organic acid treatments, C. jejuni counts were reduced by 0.36–1.98 log cfu/cm2 as compared to the control samples treated with tap water. C. jejuni counts decreased significantly on leg (P < 0.05) and breast meat (P < 0.01) during storage at 4C. Although the pathogen survived in all samples during 6 months of storage at−18C, its level decreased significantly (P < 0.01) in both leg and breast meat samples. It was concluded that the treatment of chicken parts with LA or AA was effective especially for reducing initial C. jejuni population. PRACTICAL APPLICATIONS Because contamination of chicken meat with Campylobacter spp. is unavoidable, there is need for a decontamination step in poultry processing. The treatment of chicken meats with lactic acid or acetic acid, which are classified as generally recognized as safe, was found advisable for reducing the initial level of Campylobacter jejuni. Additionally, this process will be beneficial for extending shelf life of chicken parts by reducing the total microbial load.