The current study was designed to assess the efficiency of ozone (O3) as a green technology in the detoxification of aflatoxins (AFs) in luncheon and kofta. Both products can deliver AFs to consumers where all samples revealed more than one of the major AF B1, B2, G1, and G2. Kofta contained a higher level (15.2 ppb) of total AFs compared to luncheon (4.8 ppb). By exposing samples to O3, the degree of detoxification was proportional to O3 concentration. At 20 ppm O3, the most detoxified AFs were AFB2 (67.1%) and AFG1 (68.3%) while the reduction in other AFs ranged from 11.6 – 55.2% and 44.7 – 61.4% for luncheon and kofta, respectively. By 40 ppm O3, the most detoxified AFs were AFG1 (100%) and AFB2 (91.7%) while the reduction in other AFs ranged from 54.6 – 85.7 % and 61.4 – 78.4%, respectively. By the two applied concentrations, O3none significantly lowered the pH values of samples. Lipid stability was inversely proportional with O3 concentration as fat was more stable at 20 compared to 40 ppm O3, where kofta appeared higher stability compared to luncheon. Ozone appeared able to eliminate or significantly reduce AFs in raw and ready-to-eat meat products with negligible changes in physicochemical properties.

In the present study, the efficiency of sodium acetate (2.5% wt/vol), lactic acid (2% vol/vol), citric acid (2% vol/vol), calcium chloride (3% wt/vol), Nisin (0.04 g/L), Lactic acid (2% vol/vol), and nisin (0.04 g/L), combination solutions as additional hurdle to refrigeration (4°C) of tilapia was evaluated. The solutions were applied as surface coating by dipping method. The effects of treatment on bacterial population (APC, Psychrotrophic species, Enterobacteriaceae, and sulfite reducing anaerobes), pH, Total volatile basic nitrogen, Thiobarbituric acid number, and sensory attributes were evaluated during 10 days of refrigerated storage. Based on the quality indexes, nisin and lactic acid combination is the choice of additional hurdle to extend the shelf life of tilapia for two additional days to control without deviation in the sensory quality. Lactic acid appeared an alternative hurdle. Correlation studies indicated APC is a good freshness indicator while pH is a good index of spoilage for tilapia under refrigerated storage. Practical applications Provide fish processors with applicable materials to extend the shelf life of fish under cold storage. In summary, by using nisin–lactic acid combination or lactic acid alone fish can be stored and distributed under safe hygienic conditions. That will be reflected in advances in the food industry and consumer protection.

A surveillance study of retail foods was conducted in Assiut, Egypt to assess the presence of Arcobacter spp. on retail food samples. A total of 75 fresh samples of beef, minced beef, and fish (Oreochromis niloticus), 25 each were purchased from fresh markets in Assiut city and tested for Arcobacter spp. The survey was carried out by differential culture, phenotying and genotyping. A total 35 (47 %) of samples was contaminated with Arcobacer spp. Beef was the most contaminated 13(52%) followed by minced beef 12(48%) then fish 10 (40%). By genotyping using PCR, only a total 11 (15%) of samples harbor Arcobacter spp. Five (20%) of beef, 2 (8%) of minced beef and 4 (16%) of fish were contaminated with Arcobacter spp. When the isolates were confirmed by genus-based PCR, A. butzleri, A. skirrowii and A. cryaerophilus were present in a total 4 (5%), 5 (7%) and 2 (3%) of examined retail foods. The highest A. butzleri contamination level was in beef samples 2 (8%). A. cryaerophilus, A. skirrowii and A. butzleri were examined for their susceptibilities to antibiotics using a disk-diffusion method. All were resistant to Lincomycin, Vancomycin, Tetracycline. Cloxacillin, Cephradine, Novobiocin and Oxacillin but susceptible to Gentamycin and Neomycin. With the exception of A. cryaerophilus the tested Arcobacters were susceptible to Ciprofloxacillin. The effect of sodium acetate (SA) and sodium chloride (SC) on growth inhibition of Arcobacter spp. was investigated by determining the minimum inhibitory concentration (MIC) and the minimum lethal concentration (MLC). Sodium acetate provided overall greater inhibition in comparison with (SC). The MLCs were 6% and 9% for of (SA) and (SC), respectively. The corresponding MIC values were 4% and 6%, respectively. The combined effect of (3% SC) and SA at different concentrations (0.01 -0.05%) were tested against A. butzleri in the growth medium. A significant (P ˂ 0 .05) reduction level of A. butzleri cells was obtained by the combination of 3% (SC) and 0.04 or 0.05% (SA). The greatest reduction (2.7 log) was achieved by the combined effect of 3% (SC) and 0.05% (SA). In minced beef model, (3% SC + 0.05% SA) mixture took 12 h to produce 1 log reduction in the initial A. butzleri count and the reduction was proximate at 24h period. The difference in A. butzleri count between treatment and control samples was significant (P ˂ 0.05). The present study identified beef and minced beef as important food sources of A. butzleri which pose a threat for human health. Also it cleared that fish at retail has been detected to be a further food matrix for A. butzleri. Regarding the enteropathogen A. butzleri, (3% SC + 0.05% SA) mixture can improve the safety of minced meat under refrigerate storage. This study also shows that Gentamycin would be drugs of choice and Neomycin as alternative for treatment of Arcobacter borne gastrointestinal infection in this geographical area. The public health significance of Arcobacter spp. and the control measures were also discussed.

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The present study was designed to investigate the occurrence of Listeria spp. in two of economically important freshwater fish species namely Oreochromis niloticus (tilapia) and Clarias gariepinus which were collected from commercial fish markets in Assiut, also to explore the efficiency of five ice formulations : tab water ice (control), three ices sanitized using trisodium phosphate (TSP) 2.5%,5% and 10% in addition to an ice sanitized using sodium acetate (SA) 2.5% against Listeria monocytogenses (LM) artificially loaded on Tilapia fish at level of (5.5log10 CFU/g) and the effect of formulated ices on ice stability, sensory quality and pH of fish during storage at room temperature (25 ºC). The microbiological analysis of sampled fish revealed that sampled fish represents health hazard to consumer and contact surfaces. O. niloticus were more contaminated with Listeria spp. compared with C.gariepinus samples (16%and 4%, respectively). The contamination with LM in both fish species was parallel (4%) while Listeria innocua was present in O. niloticus only (12%). Storage of Tilapia loaded with LM (5.5 log10CFU/g) on formulated crushed ices separately for 4h revealed that both (SA) 2.5% and (TSP) 10% ices had the efficacy (P>0.05) of reduction of LM on fish and in water from melted ice when compared with the control thus improves the safety and reduces the potential for cross contamination. Formulated ices were more stable (slow melting rate) when compared with the control. Storage of fish on formulated ices for 4h was not associated with any defects in sensory parameters (P>0.05). A desirable lowering of pH values of stored fish was noticed by application of (SA) 2.5% ice while (TSP) 10% ice resulted in a significant rise (P<0.05) of pH at the end of storage period. Despite this study demonstrates the effectiveness of (SA) 2.5% ice or (TSP) 10% ice application to control the growth of LM to enhance the microbiological safety of raw fish, (SA) 2.5% ice has the advantages of its organic origin and its desirable lowering pH of stored fish. The public health importance of the organism was discussed and the suggestive measures for control were outlined.