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Kročko M., Čanigová M., Ducková V., Artimová A., Bezeková J., Poston J. (2011): Antibiotic resistance of Enterococcus species isolated from raw foods of animal origin in South West part of Slovakia. Czech J. Food Sci., 29: 654-659.We determined the prevalence and antibiotic resistance of enterococci isolated from raw foods of animal origin. All samples were positive for enterococci. The lowest count of enterococci was found in pork (2.00 log CFU/cm 2 ), while bryndza cheese contained the highest count (4.99 log CFU/g). Among the 349 Enterococcus isolates, 49% were E. faecalis, 29% E. faecium, and 13% Enterococcus spp. Tetracycline and gentamicin resistance was the most common. We found the highest tetracycline resistance levels (91%) in isolates from poultry samples. The isolates from the poultry samples also displayed multidrug resistance to all antibiotics tested. The most common vancomycin-resistant species in poultry and milk was E. faecalis. In contrast, the pork samples contained vancomycin-resistant E. faecium isolates.It is interesting to note that vancomycin resistance in the pork and poultry samples was found only in combination with either four (28%) or all five (14%) of the tested antibiotics. Our results suggest that raw products of animal origin are possible reservoirs of multi-antibiotic resistant enterococci in the food chain.

The present experiment was aimed to study the eff ect of the propolis extract as supplement diet on the broiler chickens growth performance, breast and thigh weights, meat chemical composition and lipid oxidation stability. A total of 120 chicks in one day old, which were divided into 4 groups (n = 30) for 42 days.To the experimental groups were added propolis extract in doses of 200 mg.kg −1 (II), 300 mg.kg −1 (III) and 400mg.kg −1 (IV). At the end of the experiment the results were shown that the body weight gain a er 21 and 42 days has been increased and there were found signifi cant diff erences (P ≤ 0.05) between control and experimental groups also the feed intake has been increased and there were (P ≤ 0.05). The FCR was higher in the control group. The carcass body weight breast and thigh weights were increased and there were no signifi cant diff erences while, the abdominal fat and liver weights were decreased. No signifi cant diff erence was occurred on chemical composition of breast and thigh muscles, whereasthe muscle moisture tends to increase and fat content and energy value were decreased. Interestingly, thelipid oxidation stability measured as TBARS during the freezing storage for 6 months has been decreasedmalondialdehyde (MDA) in the experimental groups and there were found signifi cant (P ≤ 0.05) in the breast musclesbetween control group and experimental groups. From the present study were concluded a er administration the propolis extract that broilergrowth performance has been increased and the lipid oxidation (MDA) during the freezing storage (−18 °C) have been decreased.

The effect of 0.06% propolis ethanol extract on the sensory quality, colour and oxidative stability of cured cooked ham was evaluated. Half of the experimentally processed hams treated with 0.06% ethanolic extract of propolis with ascorbic acid (EEP), only with ascorbic acid (AA) and control samples (C) were sliced and vacuum packaged. Samples were kept at 4 °C 21 days (sliced) respectively 20, 50 and 100 days (unsliced). The results revealed that all samples were characterized without any significant colour discrepancies. In general, the thiobarbituric acid value (mg malondialdehyde/kg) increased gradually in all samples examined, with a significantly lower (P <0.05) level for treated samples than for controls. The significantly lowest (P <0.05) sensory parameters in comparison to unsliced hams were observed in sliced hams packaged in vacuum. Sliced hams with EEP were characterized with significantly lowest (P <0.05) intensity of characteristic aroma. Undesirable taste was detected in control sliced hams after storage period. Significantly (P <0.05) more desirable taste of sliced hams was observed in those with only ascorbic acid in comparison with EEP. In our study was demonstrated that 0.06% ethanol extract of propolis positive affected oxidation stability and not negative affected others technological (pH, colour) and sensory characteristics of poultry meat product - cured cooked ham.

Oxidation is one of the most prevalent factors responsible for meat product deterioration. Due to their potential health risks, commonly used synthetic antioxidants are beginning to be frowned upon by customers. The industry is searching for a natural replacement. In our study, we incorporated blackcurrant (Ribes nigrum L.) and Kamchatka honeysuckle (Lonicera caerulea var. Kamtschatica) extracts into raw-cooked meat products (frankfurters) as natural antioxidants. We observed that both extracts at concentrations of 3 mL·kg−1 were able to significantly (α = 0.05) postpone lipid oxidation in our samples, with results comparable to vitamin C (0.5 mg·kg−1) addition. Moreover, we did not observe negative effects of the extracts on the product’s color, pH, or textural properties. Negative results were reported in the sensory evaluation of honeysuckle addition samples. This could have been caused by the natural strong and bitter taste of honeysuckle, which was transferred to the extracts and, subsequently, into the meat product.