Oxidative stability of chicken meat during storage influenced by the feeding of alfalfa meal

The aim of our experiment was to determine the effect of the alfalfa meal component in feed mixtures of Ross broiler chickens on oxidative stability of meat. Proportion of alfalfa meal in feed mixtures was 4 and 6%. The results were compared to the control group without alfalfa meal in feed mixtures. At the end of the experiment (day 38), 6 pcs of broiler chickens from each group with an average live body weight over 1 800 g were randomly selected. The samples for chemical analysis consisted of identical proportion of breast and thigh muscle, and about 1 cm2 of skin with subcutaneous fat. Fat from the meat was obtained after the samples drying. A fat was determined by extraction by means of laboratory instrument Det N Gras Selecta P. The oxidative stability of meat on the basis of acid number of fat was determided by chemical analysis. Chicken meat was stored at -18 °C for 12 months and 18 months. The acid number of fat of stored meat for 12 months was 7.38 mg KOH per g in the control group, 7.42 mg KOH per g in the group with a proportion of 4% alfalfa meal, and 11.18 mg KOH per g in the group with proportion 6% alfalfa meal. An acid number of fat of stored meat for 18 months was 5.90 mg KOH per g in the control group, 4.65 mg KOH per g in the group with a proportion of 4% alfalfa meal, and 7.07 mg KOH per g in the group with a proportion of 6% alfalfa meal. Chicken meat is notably sensitive to lipid oxidation because of its high content of polyunsaturated fatty acids. Legislation in Title 5 of Part 3 of the Codex Alimentarius of the Slovak Republic and the Government Regulation No. 286/2003 Coll. in the Annex 4 in Part B provide the requirements for animal fats and meat products. Regulation of the European Parliament and Council (EC) No. 853/2004 lays down specific hygiene rules for food of animal origin. In particular, determination of free fatty acids content of rendered animal fat (tallow, lard, other animal fat). Legislative regulation does not contain requirements for the quality of chicken meat, the acid number of  fat of fresh or frozen chicken meat, respectively. A chicken meat is preferred over other kinds of meat. It is characterized by certain dietary and nutritional properties that consumer prefers. A price of this kind of meat remains attractive. In terms of human health, oxidative stability of chicken meat is important, especially of stored meat. In general terms, the various food additives are currently used to maintain the food stability. Great attention is currently paid to additives of natural origin. Similar focus is presented in our study. We can state, on the basis of the oxidative stability results of chicken meat, that natural feed component has its justification. This issue requires further research

Oxidative stability of chicken meat after propolis extract application in their diets

In the experiment, the effect of the addition of propolis extract in a feed mixture for chicken broilers Hubbard JV on oxidative stability of breast and thigh muscles during refrigerated storage was investigated. In the experiment were included 90 pieces of one day-old chicks, which were divided into 3 groups (control, E1 and E2). Chickens were fed by ad libitum system until the age of 42 days. These feed mixtures were made without antibiotics preparation and coccidiostats.  Propolis extract in an amount of 150 mg.kg-1 (E1) and 450 mg.kg-1 (E2) was added into feed mixtures for experimental groups. During whole period of refrigerated storage were higher values of MDA determined in control group compare to experimental groups. The higher average MDA value determined in breast muscels of broiler chicken hybrid combination Hubbard JV was in samples of control group (0.157 mg.kg-1) compared to experimental groups E1 (0.140 mg.kg-1) and E2 (0.130 mg.kg-1) after 6-month of refrigerated storage. Significantly higher values of MDA were determined in control group compare to second experimental group from fourth month to the end of storage. The significantly lower value of MDA was determinated in first experimental group compare to control only at 6 month of storage. Trend of thigh muscle oxidation stability of chicken hybrid combination Hubbard JV was during 6 months of refrigerated storage similar than in breast muscle. The higher average MDA value determined in thigh muscels was in samples of control group (0.170 mg.kg-1) compared to experimental groups E1 (0.150 mg.kg-1) and E2 (0.139 mg.kg-1) after 6-month of refrigerated storage. Significantly higher values of MDA were determined in control group compare to second experimental group from fourth month to the end of storage. Higher amount of MDA in thigh muscle compare to breast muscle is due to by higher amount of fat occurred in thigh muscle

The prevalence of Salmonella infections in laying hen flocks producing eggs and their impact on the public health

Since 2008, Slovakia has implemented the National control program of Salmonella infections in laying hen flocks. This program requires the farm operators to monitor and investigate the invasive types of Salmonella (S. Enteritidis and S. Typhimurium) according to STN ISO 6579. The aim of this study was to perform a microbiological examination of dust and chicken droppings samples of laying hens in the Trenčín region for the presence of Salmonella by Horizontal method according to STN ISO 6579: 2002, to compare results with the statistics across Slovakia and selected EU countries and to evaluate the impact of official controls of salmonellosis in animals and humans.  In the years 2009 - 2013 in the Trenčín region, 730 samples of dust from the conveyor belts and droppings of laying hens were taken to determine the prevalence of Salmonella in individual rearings. In these years, the incidence of positive samples was found from 0% to 29.17%. For the period from 2009 till 2013 was reported 22833 salmonellosis cases in human population of Slovakia, while in the Trenčín region it was 2636. Five-year EU-trend (2009 - 2013) showed a statistically significant decrease of salmonellosis occurence (with a mean reduction of 12% per year). The Wilcoxon signed-rank test was performed in order to provide in-depth epidemiological assessment of salmonellosis cases in Trenčin region in relation to selected characters: etiological agens, transmission mechanism, age, location as well as seasonality of infection

The effect of dietary alfalfa meal on the chicken meat quality

The purpose of this study was to investigate the effect of feed mixtures with proportion of alflafa meal 4% on body weight of broiler chickens, fat content their meat and oxidative stability meat fat under storage conditions. Final hybrid Cobb 500 chickens were used in the experiment. The broiler chickens were fed with feed mixtures starter from the 1st to the 18th day, grower from the 19th to the 31st day and finisher from the 32nd to the 38th ad libitum. An alfalfa meal of 4% was added in the feed mixtures of experimental group. In our experiment, we used alfalfa meal, which was made from Medicago sativa L. harvested in the bud's phase. The carcasses of broilers were stored at -18° C for a period of nine months. The average weight of chickens at the end of our experiment, the control group was 1685.6 g. In experimental group with addition of 4% alfalfa meal in feed mixtures, the chickens weighed 1709.6 g. The difference in body weight between the groups was not statistically significant (p >0.05). The average fat content in chicken meat was lower in the group with a share of 4% alfalfa meal 2.33 g.100g-1 compared to the fat content in meat chickens control group 2.59 g.100g-1. Differences in fat content in meat between the groups were not statistically significant (p >0.05). In our experiment, the average peroxide value of fat in meat under storage conditions 9 months at -18°C was lower in the group with a share of 4% alfalfa meal 2.42 µmol O2.g-1 compared with an average value of peroxide number 5.79 µmol O2.g-1 in the control group. Medicago sativa L. is an interesting object for research. It is characterized by high content of protein and biologically active substances that are effective for the promotion of health, and also an improvement the nutritional value and technological properties of the poultry food, when is used in feed mixtures

Oxidative stability of chicken thigh meat after treatment of abies alba essential oil

In the present work, the effect of the Abies alba essential oil in two different concentrations on oxidative stability of chicken thigh muscles during chilled storage was investigated. In the experiment were chickens of hybrid combination Cobb 500 after 42 days of the fattening period slaughtered.  All the broiler chickens were fed with the same feed mixtures and were kept under the same conditions. The feed mixtures were produced without any antibiotic preparations and coccidiostatics. After slaughtering was dissection obtained fresh chicken thigh with skin from left half-carcass which were divided into five groups (n = 5): C - control air-packaged group; A1 - vacuum-packaged experimental group; A2 - vacuum-packaged experimental group with thylenediaminetetraacetic acid (EDTA) solution 1.50% w/w; A3 - vacuum-packaged experimental group with Abies alba oil 0.10% v/w and A4 - vacuum-packaged experimental group with Abies alba oil 0.20% v/w. The Abies alba essential oil was applicate on ground chicken things and immediately after dipping, each sample was packaged using a vacuum packaging machine and storage in refrigerate at 4 ±0.5 °C. Thiobarbituric acid (TBA) value expressed in number of malondialdehyde was measured in the process of first storage day of 1st, 4th, 8th, 12th and 16th day after slaughtering and expressed on the amount of malondialdehyde (MDA) in 1 kg sample. The treatments of chicken things with Abies alba essential oil show statistically significant differences between all testing groups and control group, where higher average value of MDA measured in thigh muscle of broiler chickens was in samples of control group (0.4380 mg.kg-1) compared to experimental groups A1 (0.124 mg.kg-1), A2 (0.086 mg.kg-1), A3 (0.082 mg.kg-1) and A4 (0.077 mg.kg-1) after 16-day of chilled storage. Experiment results show that the treatment of chicken thigh with Abies alba essential oil positively influenced on the reduction of oxidative processes in thigh muscles during chilling storage and use of essential oil is one of the options increase shelf life of fresh chicken meat

Oxidative stability of chicken’s breast after vacuum packaging, EDTA, sage and rosemary essential oils treatment

In the present work, the effect of the sage and rosemary essential oils on oxidative stability of chicken breast muscles during chilled storage was investigated. In the experiment were chickens of hybrid combination Cobb 500 after 42 days of the fattening period slaughtered.  All the broiler chickens were fed with the same feed mixtures and were kept under the same conditions. The feed mixtures were produced without any antibiotic preparations and coccidiostats. After slaughtering was dissection obtained fresh chicken breast with skin from left half-carcass, which were divided into five groups (n = 5): C - control air-packaged group; A1 - vacuum-packaged experimental group; A2 - vacuum-packaged experimental group with EDTA solution 1.50% w/w; A3 - vacuum-packaged experimental group with Salvia officinalis L. oil 2.0% v/w and A4 - vacuum-packaged experimental group with Rosmarinus officinalis L. essential oil 2.0% v/w. The sage and rosemary essential oils were applicate on surface chicken breasts and immediately after dipping, each sample was packaged using a vacuum packaging machine and storage in refrigerate at 4  ±0.5 °C. The value of thiobarbituric acid (TBA) expressed as amount of malondialdehyde (MDA) in 1 kg sample was measured during storage in 1st, 4th, 8th, 12th and 16th day. The treatments of chicken breasts with sage and rosemary essential oils show statistically significant differences between all testing groups and control group, where higher average value of MDA measured in breast muscle of broiler chickens was in samples of control group (0.396 mg.kg-1) compared to experimental groups A1 (0.060 mg.kg-1), A2 (0.052 mg.kg-1), A3 (0.042 mg.kg-1) and A4 (0.041 mg.kg-1) after 16-day of chilled storage. The results of experiment showed that the treatment of chicken breast with sage and rosemary essential oils had positive effect on the decrease of oxidative processes in breast muscles during chilling storage and use of plant essential oils is one of the possibilities increase shelf life of fresh chicken meat

Influence of different curing methods on the fatty acid composition in sausages prepared from red deer meat

These curing agents play a decisive role in obtaining the specific sensory properties, stability and hygienic safety of products such as fermented sausages, ham and, more recently, emulsion type of sausages. The effect of using two different curing agents (sodium chloride and nitrate) on fatty acid compounds in dry-cured deer meat was investigated in our study. The concentration of free fatty acids in the fat depends on the hydrolytic activity of the lipases, the microbial metabolic processes, and the oxidative reactions that work on the free fatty acids released in the lipolysis. The main identified fatty acids in all different types of curing were palmitic acid (16 : 0), oleic acid (c18 : 1 cis-9), stearic acid (C18 : 0). The resulting n-6/n-3 PUFA ratio in the muscle samples of red deer showed no variation in different types of curing and was beneficially low within the range of 3.9 : 1 and 4.49 : 1. Total free fatty acids, whether saturated, monounsaturated or polyunsaturated fatty acids, did not increased (p >0.05) greatly through the processing of dry-cured deer meat. Also there was no effect of curing method on fatty acids composition in two different muscles Semitendinosus muscle (ANOVA, p >0.05, F - 0.003, F crit. - 3.041) and Triceps brachii muscle (ANOVA, p >0.05, F - 0.05, F crit. - 3.01). There were found no significant (p >0.05) differences between fatty acids content in sausages prepared by brining in NaCl and Nitrate salt. The present study revealed that game meat can function as a good source of bioactive compounds that are essential for human nutrition

Effect of thyme and oregano aqueous tea infusions on the lipid oxidation and sensory characteristics of frankfurkters sausages

Lipid oxidation is one of the main limiting factors for the quality and acceptability of frankfurkter type of sausages. The antioxidant activity has been measured using a TBA assay. Dried oregano (Origanum vulgare) and thyme (Thymus vulgare) were purchased from a local store and kept in dark until the use. Aqueous extracts were prepared by one-step extraction with 3 g of each pulverized plant. Samples of freshly cooked sausages were evaluated by a 6 member semi-trained panel of laboratory co-workers. Panelists evaluate appearance overall texture, flavour, aroma and overall acceptability on a 6 point hedonic scale. In this work the antimicrobial and antioxidant effect of Thymus vulgare and Origanum vulgare significantly reduced (p <0.05) lipid oxidation in frankfurkters sausages on 10th day of aerobic storage. The organoleptic changes in sausages had no negative effect on the sensory value of cooked sausages. Results obtained in this work indicated the technical viability of using the oregano and thyme aqueous tea infusions in relative low concentration, which is possible to enlarge the shelf-life of fresh sausages with the desired slight alteration of the original taste parameters. Results indicate that thyme and oregano aqueous tea infusions compare to essential oils can be cheaper alternative incorporate into pork frankfurkters as natural antioxidants

Influence of propolis extract in Hubbard JV chickens nutrition on oxidative stabilty of meat

DOI: 10.15414/afz.2014.17.02.47–51Received 12. May 2014 ǀ Accepted 3. June 2014 ǀ Available online 23. June 2014In the experiment we evaluated the influence of propolis extract in nutrition of chickens on stability of meat in the most valuable parts of carcass that were stored by freezing at -18 °C. The hybrid combination of tested chickens was Hubbard JV. Propolis extract was added to experimental groups at a dose of 600 mg.kg-1 (group E1) and 800 mg.kg-1 (group E2). Fattening lasted 42 days. Oxidative stability of breast and thigh muscles was evaluated from the 1st day to 6th month of storage in regular month intervals. In the breast muscle, values of malondialdehyde (MDA) were from 0.212 to 0.313 mg.kg-1 in control group, from 0.186 to 0.264 mg.kg-1 in E1 group and from 0.175 to 0.259 mg.kg-1 in E2 group. In the thigh muscle, MDA values were from 0.255 to 0.339 mg.kg-1 (control group), from 0.196 to 0.279 mg.kg-1 (E1 group) and from 0.194 to 0.268 mg.kg-1 (E2 group). Application of propolis extract in Hubbard JV chickens nutrition has significant influence (P≤0.05) on decreasing of oxidative processes in breast and thigh muscles during the whole period of storage.Keywords: chickens, nutrition, feed supplements, propolis, chicken meat, oxidative stability, malondialdehyd

Evaluation of meat quality after application of different feed additives in diet of broiler chickens

The present study was conducted to investigate the effect of natural feed additives, namely bee pollen extract, propolis extract and probiotic preparation, on technological properties of meat in order to evaluate the meat quality of Ross 308 broiler chickens.  The feeding of chickens (180 pcs) lasted for a period of 42 days. The experiment was carried out without segregation between the genders. The chickens were randomly divided into 4 groups. The control group was fed a basal diet, whereas the other three groups were fed diets supplemented with natural additives, i.e. bee pollen extract at level of 400 mg.kg-1 of feed mixture, propolis extract at level of 400 mg.kg-1 of feed mixture, and probiotic preparation based on Lactobacillus fermentum (1.109 CFU per 1 g of bearing medium) in an amount of 3.3 g added to water (for 30 pcs chickens until 21 days of age, for 20 pcs chickens from 22nd to 42nd day of age) given to group E1, group E2 and group E3, respectively. The feed mixtures were produced without any antibiotic preparations and coccidiostatics. During the whole period of experiment, the broiler chickens had ad libitum access to feed and water. The following technological properties were examined: cooling loss (after 24 h of storage at 4 °C), freezing loss (after 3 months of storage at -18 °C), roasting loss (performed on roasted meat that was stored at -18 °C for 3 months before thawing), colour parameters based on CIELab system (the L*, a*, b* values of raw breast and thigh muscle), and tenderness (as shear force of roasted breast and thigh muscle). We have made a finding, that the examined additives had only little impact on meat quality in most of the investigated parameters, except the significant increase (p ≤0.05) in redness (a*) values and the slight decrease in roasting loss and shear force determination after propolis extract supplementation. Therefore, it may be inferred that propolis extract has been shown as the most appropriate feed additive among the applied supplements