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Salmonella enterica serotype Enteritidis is an important alimentary pathogen that recently gained special attention due to the ability of a large number of strains to form biofi lms. Qualitative testing of biofi lm forming ability was performed by observing the morphotype of the colonies on Congo Red agar and by conducting the pellicle test, while quantitative testing was carried out by Cristal violet assay on microtiter plates. A total of 14 isolates of S.Enteritidis were tested for biofi lm forming ability, while Salmonella Enteritidis ATTC 13076 was used as the reference strain. Based on the morphotype of colonies cultivated on Congo Red agar at 25°C incubation temperature, among tested isolates three morphotypes were detected -red, dry and rough (rdar), brown, dry and rough (bdar) and smooth and white (saw). Half of the tested isolates demonstrated rdar morphotype. All isolates that showed a specifi c morphotype at this incubation temperature also formed the corresponding type of pellicle at the air-liquid interface. Additionally, comparing OD (optical density) values obtained by crystal violet test between groups of isolates that represent one of the three detected morphotypes (rdar, bdar and saw), statistically signifi cant differences were detected. Based on OD values obtained by crystal violet test at both applied incubation temperatures, isolates were classifi ed into three categories, regarding their ability to form biofi lms: strong, moderate and weak biofi lm producers. By comparing the amounts of the biofi lms formed after 48h at 25°C and 37°C, statistically signifi cant differences were noted (P<0.05). In this research we presented micrographs and a reconstruction of threedimensional projections of biofi lm developing phases of rdar morphotype isolates, which were obtained using confocal laser scanning microscopy.

In this study, fungal contamination was determined as well as total aflatoxin B1(AB1), ochratoxin A (OTA) and zearalenon (ZEA) levels in corn-based feed samples obtained from four different farms in Serbia (n=35) during one year. Mycotoxins were detected in feed using the VICAM fluorometric method. It was determined that 97.14% of all samples were contaminated with moulds which belonged to following genera: Absidia, Acremonium, Aspergillus, Cladosporium, Geotrichum, Eurotium, Fusarium, Mucor, Mortierella, Oidiodendron, Penicillium, Rhizopus, Scopulariopsis, Syncephalastrum, Trichoderma, Ulocladium and Wallrothiella. A total of 58 different species were identified. Total mould count per 1 g ranged from 1.00 log cfu/g (dried corn silage - autumn, fresh corn silage - summer and corn grain silage - spring) to 7.32 log cfu/g (dried corn silage - winter). Mycotoxins were isolated from 28.5% of samples: ZEA was found in summer (220-240 μg/kg) and in spring (240 μg/kg) in concentrate samples; OTA was detected in winter in dried corn silage (16 μg/kg) and in spring (12 μg/kg); all samples were AB1 free

The influence of temperatures (18, 22 and 26°C), salt (60, 70 and 80 g/kg) and starter culture (0, 0.025 and 0.050 g/kg) on physico-chemical and microbiological changes during fermentation in cabbage heads were investigated. The experiment was set up in industrial conditions, samples were taken after 0, 5, 12, 27 and 62 days in order to determine the changes in color, texture, biogenic amines content, microbiological parameters, pH, aw, total sugar content, total acidity and salt content. Analysis of variance and Principal component analysis were applied to get a better overview of differences between samples and the similarities between different fermentation conditions. Significant color changes and softening of cabbage tissue did not occurred during the entire fermentation process. Cadaverine was not detected in samples containing starter culture, also the results were in range for maximum allowed putrescine and cadaverine doses for all cabbage samples. Total number of molds increased, contrary to number of yeasts on the last examined day in comparison with raw cabbage sample. Enterobacteriaceae were not detected after 5th fermentation day, while sharp increase of lactic acid bacteria number occurred until 12th day, and on the 12th fermentation day was in range of 7.82 to 9.84 log cfu/g. The fermentation process led to decrease in pH, aw and total sugar content, meanwhile total acidity 0.54%-0.89% and salt content 2.08%-3.19% in the cabbage heads increased, in comparison with raw sample where results for total acidity and salt content were 0.13% and 0.05%, respectively. Additionally, according Principal component analysis, temperature of fermentation had the greatest influence on the fermentation process, followed by the application of starter culture and then concentration of added salt.