Antimicrobial activity of Thyme (Tymus vulgaris) and Oregano (Origanum vulgare) essential oils against some food-borne microorganisms

The aim of this study was to investigate antibacterial effects of oregano and thyme essential oils (EOs) on some food-borne bacteria. GC-MS analysis of EOs was performed in order to determine their composition and phenols were predominant constituents. The investigation of the antibacterial effects of EOs was performed on Salmonella Enteritidis, Salmonella Thyphimurium, Staphylococcus aureus, methicillin resistant Staphylococcus aureus, Escherichia coli and Bacillus cereus, and MICs were determined by broth microdilution method. EOs exhibited antibacterial activity against all tested microorganisms

The effect of breed line and age on measurements of pH-value as meat quality parameter in breast muscles (m. pectoralis major) of broiler chickens

The objective of this study was to determine the effect of breed line and age on pH in broiler chicken breast muscles. pH values of m. pectoralis major muscle were compared within 6 groups - each line (Cobb, Ross, Hubbard) was divided into two groups aged 42 and 50 days. pH values were recorded 15 minutes, 24 and 48 hours after slaughtering. Older broilers showed significantly lower pH than younger ones. Interactions between breed line and age were found, except for pH after 24 hours. Meat quality of broilers can be estimated quickly by determining the pH-value of breast meat

Effect of vacuum and modified atmosphere packaging on microbiological properties of cold-smoked trout

Because of the importance of different packaging methods for the extension of fish shelf life, as a highly perishable food, the aim of the present study was to examine the effect of vacuum and modified atmosphere packaging on the total Enterobacteriaceae and lactic acid bacteria counts of cold-smoked Salmon trout (Oncorhynchus mykiss) stored at 3 degrees C during six weeks. Trout fillets were vacuumed packaged (VP) or packaged in one of two different modified atmospheres, with gas ratio of 50% CO2/50%N-2 (MAP1) and 90% CO2/10%N-2 (MAP2) and analysed on days 0, 7, 14, 21, 28, 35 and 42. Both the total Enterobacteriaceae and total lactic acid bacteria counts increased in the trout fillets in all packaging types during storage. A significantly lower total Enterobacteriaceae count was determined in the MAP fish compared to the VP fish, with the weakest growth rate and lowest numbers attained in MAP2 fillets. The lactic acid bacteria count was higher in trout packaged in MAP compared to VP, with the highest number in the MAP with 90% CO2 (MAP2)

The effects of immunocastration on male pig yield parameters and meat quality

The aim of this study was to evaluate the effects of immunocastration on pork meat and carcass quality, compared to meat from surgically castrated males and entire males. Ninety (Duroc x Pietrain) x (Landrace x Yorkshire) crossbred pigs were assigned to three experimental groups: surgically castrated males (barrows; castrated up to the seventh day of age), entire males (males), and vaccinated males (immunocastrates). Carcass and meat quality characteristics such as weight of hot and chilled carcass, meat yield, chilling loss and chemical parameters were examined. Surgically castrated pigs had significantly lower (p lt 0.01; p lt 0.05) weight before slaughter, than males and immunocastrates, and also lower (p lt 0.01) warm carcass weight than males. The average carcass meatiness of castrates was significantly lower (p lt 0.01) than the average meatiness of males and immunocastrates. Chilling loss of barrows was significantly lower (p lt 0.01) than chilling loss of males or immunocastrates. It was also found that the chilling loss of immunocastrates was significantly lower (p lt 0.05) than chilling loss of males. According to the results obtained, it can be concluded that immunocastration could be a good alternative to surgical castration considering meat and carcass quality characteristics

Comparison of bacteriological status during ripening of traditional fermented sausages filled into different diameter artificial casings

The ripening process of fermented sausages is affected by diameter and type of sausage casings, and depends on changes in the microflora, important from hygienic and technological aspects. The aim of this study was to compare the bacteriological status sausages which were stuffed in artificial collagen sausage casings of different diameters (35 mm and 60 mm) during ripening and drying. The sausage stuffing was the same, as was the uncontrolled ripening conditions. In bigger diameter sausages, significantly higher average total bacterial count, enterobacteria and lactic acid bacteria counts were found than in smaller diameter sausages

Effect of Dietary Fatty Acid Pattern on Growth Performance, Carcass Characteristics, Fatty Acid Profile, and Serum Biochemistry Parameters in Broiler Chickens

This study was undertaken to investigate the effect of dietary fat supplementation with linseed oil and/or pig lard on performance, carcass characteristics, fatty acid profile and serum biochemistry parameters in broiler chickens. In the study, 240 one-day-old Cobb 500 broiler chickens were randomly distributed to one control and three experimental dietary groups: diet supplemented with pig lard; diet supplemented with linseed oil, and; diet supplemented with a 1: 1 ratio of lard to linseed oil. The fat sources influenced serum biochemistry parameters and fatty acid profiles of drumsticks with thighs, but had no influence on growth performance or carcass characteristics. With dietary linseed oil, eicosapentaenoic acid and docosahexaenoic acid increased (P<0.05) in meat from drumsticks with thighs. Supplementation with pig lard significantly (P<0.05) increased the saturated and monounsaturated fatty acids in drumsticks with thighs. In conclusion, dietary incorporation of linseed oil and pig lard during starter, grower and finisher phases can enrich broiler chickens meat with n-3 PUFA. This study has clearly shown that linseed oil in broiler nutrition provided the best n-6/n-3 ratio

The effects of dietary Selenium-yeast level on glutathione peroxidase activity, tissue Selenium content, growth performance, and carcass and meat quality of broilers

The present study was conducted to assess effects of selenium (Se)-yeast supplementation on glutathione peroxidase activity, Se levels in tissues, growth performance, carcass, and meat composition in broilers. A total of 275 one-d-old Cobb 500 broilers of both sexes were randomly allotted to 1 of 5 treatments during a 42-d period. The 5 treatments differed only in Se content: group 1 had no additional Se (background only); groups 2, 3, and 4 received 0.3 mg/kg of added Se from the beginning of the trial until d 21, whereas in the second half of the study (from d 22 to 42), these groups received 0.3, 0.6, and 0.9 mg/kg of added Se, respectively; and group 5 received 0.9 mg/kg of Se for the entire experimental period. At the end of the study, the control group showed significantly lower (P < 0.01) glutathione peroxidase activity in blood plasma compared to Se-supplemented groups. Regarding Se concentration in various tissues, the groups receiving Se yeast showed higher plasma, feces, and meat Se contents than the control group (P < 0.01). Supplementation of Se improved broilers body weight, weight gain and feed conversion ratio (P < 0.01). Dressing percentage was lower in the control group and the group with 0.3 mg/kg of added Se compared to other experimental groups (0.6 and 0.9 mg/kg of dietary Se). The proportion of less valuable carcass parts (wings and legs) was higher (P < 0.01) in the group fed the basal diet compared to groups supplemented with 0.9 mg/kg of Se. Initial and ultimate pH values differed among experimental groups (P < 0.05). Supplementation of Se improved the broilers antioxidative resistance, growth performance, carcass quality, and chemical composition of meat

Temperatures, cleanliness and food storage practises in domestic refrigerators in Serbia, Belgrade

Consumers knowledge about proper household practises during food handling and storage are deemed insufficient. Therefore, the aim of our study was to investigate the conditions of food storage in refrigerators (temperature, hygienic and storage conditions) and consumer knowledge about good practises. This study included 100 households from the Belgrade area. All participants were interviewed using a standardized questionnaire. The internal temperature of refrigerators was measured at three points: the top and bottom shelves and the refrigerator door. The average temperature in the refrigerators was 9.3 degrees C. The average temperature recorded in the refrigerator doors was significantly higher (P<0.01) than temperatures recorded on the top or bottom shelves. The age and design of refrigerators, and potential heat source near refrigerator can impact the refrigerator temperature. In 50% of the surveyed refrigerators, food storage practises were incorrect. More than a half (56%) of the surveyed consumers were aware of the recommended refrigerator temperature, but measured temperature in their refrigerators was considerably higher. The results from our study indicate that knowledge of recommended behaviour about good food safety practise do not always translate into practise in the home

Antioxidative Activity of Thyme (Thymus vulgaris) and Oregano (Origanum vulgare) Essential Oils and Their Effect on Oxidative Stability of Minced Pork Packaged Under Vacuum and Modified Atmosphere

The antioxidant stability of minced pork treated with thyme and oregano essential oils (EOs) was determined. Minced pork containing different concentrations (0%, 0.3%, 0.6%, or 0.9%) of thyme (TEO) or oregano essential oil (OEO) and packaged under vacuum or modified atmosphere (MAP) (30%O-2/50%CO2/20%N-2) was evaluated within 15 days of refrigeration (3 +/- 1 degrees C) storage. EOs were examined for scavenging capacity toward 2,2-diphenyl-1-picrylhydrazyl, nitric oxide radicals, and hydroxyl, and inhibition of lipid peroxidation and ferric ion reducing antioxidant power (butylated hydroxytoluene was used as positive controls). The order of antioxidative effectiveness was as follows: butylated hydroxytoluene > OEO > TEO, with significant differences between agents (P < 0.05). Lipid oxidation in meat was determined by monitoring malondialdehyde (MDA) formation and lipolysis was assessed by measuring the acidity index immediately and after 3, 6, 9, 12, and 15 days of storage. EOs significantly (P < 0.05) increased the stability of minced pork with respect to lipid oxidation compared with the control, and the antioxidative effect was dose-dependent. Moreover, vacuum packaging resulted in mince with significantly lower oxidation and lipolysis levels than modified atmosphere packaged mince (P < 0.05). The results demonstrate that both EOs examined effectively reduced lipid oxidation in raw pork mince after 2 weeks storage. Practical Application The natural food preservatives market is growing rapidly, as is high demand for organic foods. These results are likely to be of interest to the scientists, researchers, and persons who work in the meat industry. Results and discussion can contribute to a better understanding of antioxidative properties of essential oils in food model. Furthermore, no study has reported the effect of these MAP on pork oxidative stability

Effects of selenium source and level in diet on glutathione peroxidase activity, tissue selenium distribution, and growth performance in poultry

Today, a few differing sources of selenium (Se), i.e. inorganic, organic, and nano forms of Se, are used as feed supplements for poultry. Published research indicates that nano-Se and organic Se possess comparable efficiency to inorganic Se in increasing GSH-Px activity of plasma and various tissues, but they deposit at higher rates in various tissues. However, there are principal differences in absorption mechanisms, metabolism, and efficiency of these three forms of Se. The aim of this review was to analyze the available literature on the effects of different Se sources and levels in the diet on glutathione peroxidase (GSH-Px) activity, tissue Se distribution and growth performance in poultry. Higher levels of Se increase GSH-Px activity in the body, but this reaches a plateau even if Se concentrations in diet increase further, while the deposition of Se in tissues increases as Se content in diet increases. In addition, many studies have shown the positive effects of adding Se to diet on growth performance in poultry. Optimal Se supplementation is necessary not only for good poultry health but also to ensure and preserve meat quality during storage and to provide human beings with this microelement