József Farkas

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Despite substantial efforts in avoidance of contamination, an upward trend in the number of outbreaks of foodborne illnesses caused by nonsporeforming pathogenic bacteria are reported in many countries. Good hygienic practices can reduce the level of contamination but the most important pathogens cannot presently be eliminated from most farms nor is it(More)
Historically, the ability of foods to support the growth of spoilage organisms and food-borne pathogens has been assessed by inoculating a food with an organism of interest, and following its growth over a period of time. Information gained from such challenge tests, together with knowledge of the organoleptic stability of the product, can then be used to(More)
Friesian steers (n=5), aged 26-27 months, were fed a diet containing 2000 (supplemented) IU α-tocopheryl acetate/head/day for approximately 50 days prior to slaughter. Muscularis semimembranosus muscles from supplemented cattle were held in frozen storage (-20°C×12 weeks) following which they were minced and divided into five batches. The batches contained:(More)
With the alkaline sucrose gradient centrifugation method, it was found that dormant spores of Clostridium botulinum subjected to 300 krads of gamma radiation showed a distinct decrease in deoxyribonucleic acid (DNA) fragment size, indicating induction of single-strand breaks (SSB). A two- to threefold difference in radiation resistance of spores of two(More)
Five batches of aerobically packaged minced beef from Friesian cattle were irradiated at 0, 1, 2, 3 or 4 kGy using a (60)Co irradiation source. The five batches were as follows: non-supplemented (C), dietary α-tocopheryl acetate supplemented (S), α-tocopheryl acetate supplemented with water soluble rosemary extract added after mincing (Rw), α-tocopheryl(More)
This paper attempts to summarize relevant information on microbiological safety of irradiated foods in the light of previous reports of expert committees and current literature references. After a brief survey of the relative radiation resistance of food-borne microorganisms, the importance of microbial load for dose requirement, and the role of(More)
The NaCl tolerance of different strains of Clostridium botulinum varies over a wide range, and the patterns of NaCl inhibition differ distinctly and characteristically from strain to strain. The more radiation-resistant strains, such as 33A, 62A, and 7272A, are more resistant to NaCl, whereas the more radiation-sensitive strains, such as 51B and 1304E, are(More)
The growth of untreated Listeria monocytogenes 4ab No. 10 and that of the surviving fraction of its population treated with 0.8 kGy gamma rays was investigated in a microtitreplate system at incubation temperatures between 3 degrees C and 35 degrees C in Tryptic Phosphate Broth (TPB) or Brain Heart Infusion Broth (BHIB) media containing NaCl between 0.25 to(More)
Friesian cattle, aged 26-27 months, were fed a diet supplemented with 2000IU α-tocopheryl acetate/kg feed/day and another group was fed a basal diet (20IU/kg feed/day) for approximately 50 days prior to slaughter. Following frozen storage (-20°C for 8 weeks) semimembranosus muscles from basal and α-tocopheryl acetate supplemented cattle were minced and(More)
Microbiological effects of gamma irradiation dose of 2 kGy, with and without reduction of pH to 5.3-5.2, have been investigated with a vacuum-packaged, minced meat product prepared from pork and beef with spices and cereal fillings. Either glucono-delta-lactone or ascorbic acid were used as acidulants. Experimental batches were stored at 0-2 degrees C for 4(More)