Effect of non-thermal ultraviolet and ultrasound technologies on disinfection of meat preparation equipment in catering industry.

In recent years, ultraviolet and ultrasound treatments are gaining attraction as promising green decontamination technologies to ensure microbial safety in food industry. Decontamination by ultraviolet light is a physical process defined by the transfer of electromagnetic energy from a light source to an organism's cellular material and depended on the emission of radiation in the ultraviolet region (100-400 nm), specifically the UV-C region (200-280 nm) which has been demonstrated to be germicidal. Ultrasound technology is defined as sound waves with high and low frequency beyond the limit of human hearing and shows a decontamination effect that occurs as a consequence of cavitation at high power (low frequency) in general. In the present study, it was aimed to determine the effectiveness of ultraviolet light (254 nm, 10 min) and high frequency ultrasound techniques (40 kHz, 10 min) in reducing total aerobic mesophilic bacteria, yeast and mold, Esherichia coli/coliform and Salmonella spp. on the equipment surfaces used in the catering facility. For this purpose, the equipment (cutting knife, meat grinder knife, knife sharpener, cut-proof glove) used in the meat preparation department of catering facility were selected for the treatments. According to the results, appreciable reductions were achieved in total aerobic mesophilic bacterial counts of the ultraviolet treated samples (maximum difference 2.61 log cfu/cm2) and the ultrasound treated samples (maximum difference 4.07 log cfu/cm2). After ultraviolet treatment, Salmonella spp. were totally inhibited on the contaminated surfaces. Furthermore, Escherichia coli/coliform was not detected in the samples after both treatments whereas it was detected before the treatments. It has been concluded that the techniques are effective in reducing microbiological load and also ultraviolet treatment is effective on pathogenic microorganisms on food contact surfaces. As a result, the ultraviolet and ultrasound techniques are effective treatments for equipment disinfection in the catering sector and can be used industrially as it gives successful results.

Effect of starter culture type, cooking process and storage time at -18 °C on chemical, color and microbiological qualities of fermented sucuk doner kebab.

The aim of this study was to produce fermented sucuk doner kebab and investigate the effects of starter culture type, heat treatment (82 °C) and storage time (0, 30, 90, 180 days) at -18 °C on pH, total acidity, thiobarbituric acid, residual nitrite-nitrate, color and microbiological quality. In this study, three types of starter cultures were used. These were commercial starter culture, L.sakei + S.xylosus + L.curvatus, isolated starter culture (1), L.sakei + S.xylosus + L.curvatus and isolated starter culture (2), L.sakei + S.xylosus + L.plantarum. There was also control product which contains no starter culture. The major pH decrease was observed in samples containing isolated starter cultures. Cooking and storage caused an increase in pH. Isolated starter culture was more effective than commercial starter culture in reducing residual nitrite-nitrate. Isolated starter cultures caused an increase in L* color values. The highest lactic acid bacteria count was found in sample containing commercial starter culture. Cooking was effective in inhibiting Enterobacteriaceae.

The effects of immunological castration against GnRH with recombinant OL protein (Ovalbumin-LHRH-7) on carcass and meat quality characteristics, histological appearance of testes and pituitary gland in Kivircik male lambs.

The aims of the study were to investigate the effects of immunization against GnRH using OL protein (Ovalbumin-LHRH-7) on feedlot performance, carcass, meat quality and some reproductive traits in Kivircik ram lambs. Ram lambs in the immunization (I, n=7) group were immunized against GnRH using OL protein and boosted 2 weeks later. Control (C, n=7) group was not treated. The animals were kept at pasture for 6 weeks after the first immunization, subjected to a 70 day fattening program, and then slaughtered. Growth performance, various carcass and meat quality characteristics were not affected from the immunization. GnRH immunization induced GnRH antibody production, suppressed testosterone production and testicular growth (P<0.01). Testicular structure was negatively affected from the immunization, but not pituitary. These results suggest that immunization against GnRH with OL could be an alternative castration technique in ram lambs without negatively affecting carcass and meat quality characteristics.