Oxidative Stability Of Chicken Meat Research Articles

A meta-analysis investigating the influence of citrus by-product pretreatment on lipid oxidation levels in stored chicken meat

This study extensively investigates the impact of citrus by-products on the oxidative stability of chicken meat. The literature review, spanning from 2000 to 2023, involved a thorough screening process, adhering to stringent selection criteria guided by PRISMA-P guidelines. The utilization of Hedge’s model meta-analysis to examine the distinctions between the control and treatment groups, wherein the random effect accounts for inter-study differences, and the fixed effect pertains to the impact of the addition of citrus by-product to chicken meat. Citrus by-products from various fruits, applied under diverse conditions, consistently and significantly reduced TBARS levels throughout the storage period, resulting in an overall mean effect size of -2.57 (P<0.001). While most citrus types displayed a non-significant trend with prolonged storage, both seed and peel components exhibited a significant reduction in TBARS levels (P<0.05). Notably, citrus by-products, especially in whole chicken meat and through marination pretreatment, demonstrated substantial reductions in TBARS values (P<0.01). This metaanalysis underscores the potential of citrus by-product to effectively enhance the oxidative stability of chicken meat during storage, providing valuable insights for further research and practical applications in food preservation.

Serum biochemistry, meat quality and oxidative stability in broiler chicken supplemented with a novel phytogenic feed additive formulated from P. betle, P. nigrum, A. lanata and C. dactylon

The present study investigated the effect of a phytogenic feed additive (PFA) formulated with Aerva lanata, Piper betle, Cynodon dactylon and Piper nigrum on the haematological and serum biochemical profiles in broiler chicken, and its efficacy to improve quality and oxidative stability of chicken meat. In a six-week experiment, a total of 192 day-old broiler chicks were subjected to four dietary treatments that included, basal diet+ chlortetracycline; only basal diet without chlortetracycline and PFA; and basal diet + 1 or 2% PFA. Each treatment group included six replicates of eight birds per replicate. The results showed improved albumin and cholesterol in serum of birds fed 1% PFA. The meat of birds supplemented 1% PFA showed a significant reduction in drip loss after 1 and 4 days of storage. The lipid peroxidation of breast meat measured as malondialydehyde concentration was not altered by dietary treatments at different periods of storage. Feeding 1% PFA did not induce any toxic effects on liver, kidney and spleen histology. It was concluded that the PFA when used as a feed additive improved serum biochemistry and meat quality in broiler chickens.

Oxidative stability of chicken meat at different oxygen concentrations in the packaging unit

The aim of this study was to preserve the quality and prevent the colour, lipid and protein oxidation in chicken breast fillet (pectoralis major muscle) during storage. For this purpose, modified atmospheres (MA) with four different gas mixtures (vol. %) of oxygen (O2 ), carbon dioxide (CO2 ) and nitrogen (N2 ) were used: oxygen free (0: 20: 80), low (20: 20: 60), medium (40: 20: 40), and high oxygen MA (70: 20: 10). After 9 days of storage in a refrigerator at 2 ± 1 °C, pH was measured, colour was evaluated instrumentally and sensorially, the basic chemical composition, thiobarbituric acid reactive substances (TBARs), and protein carbonyl content of raw chicken breast were determined. After thermal treatment (82 °C, 1 hour, sous-vide) of the breast fillet, the sensory characteristics of odour and aroma were evaluated, and the texture (Warner-Bratzler shear force) was measured instrumentally. The composition of the gas mixture affected all oxidation dependent parameters: (i) colour: L* and b* values were the highest under all MA with oxygen, and the a* value under MA without, medium and high-oxygen, (ii) lipids: the TBARs increased significantly under high oxygen MA after 7 days of storage (below the sensory thresholds value for rancidity), (iii) proteins: protein carbonyl content was the highest under medium and high oxygen MA, and (iv) sensory properties: colour oxidation and intensity of odd aromas under all MA with oxygen, as well as odour and aroma of stale in oxygen-free MA were increased. For chicken breast the most suitable is packaging under modified atmosphere without O2 , because the oxidation rate of colour, lipids and proteins during storage was the lowest.

The effect of oregano essential oil on chicken meat lipid oxidation and peroxidation

The study aimed to investigate and evaluate the oxidative stability of chicken thighs with skin stored in freezing conditions due to the effect of oregano essential oil for various times. The results were compared with a control group without the use of oregano essential oil. Samples of chicken thighs with skin were obtained from an experiment performed on a poultry farm in a deep litter breeding system. The results obtained from the application of oregano essential oil to chicken thighs with skin did not show a statistically significant difference (p &gt;0.05) in the dry matter content, fat content and acid value compared to the control group, where coccidiostats were used in starter and growth feed mixtures. A statistically significant difference was found in the peroxide value by applying oregano essential oil to chicken thighs with skin compared to a control group containing coccidiostats in starter and growth feed mixtures when stored for 1 day at room temperature (p £0.01) and 12 months in freezing conditions at -18 °C (p £0.05) and a statistically non-significant difference (p &gt;0.05) when thighs with skin were stored for 6 and 9 months in -18 °C freezing conditions. In the conclusion, it was stated that maintaining the oxidative stability of chicken meat means knowing the factors that affect it and prepare the conditions for its maintenance. Chicken meat is generally susceptible to oxidative damage because it is characterized by a high concentration of polyunsaturated fatty acids. With a sufficient amount of effective antioxidants, chicken meat could be a homoeostatic system, but it remains limited or free of oxidized compounds and reactive components. These questions are the subject of further research in the field of oxidative stability of chicken meat.

Dietary supplementation of Vitamin E and selenium on performance and oxidative stability of meat of broiler chickens in a hot climate

Abstract With the increase in consumers’ concern for safe food, it is highly imperative for livestock farmers to adopt feeding practices that enhance good health and high-quality products. A 49-day trial was conducted to ascertain effect of vitamin E and selenium (VE + Se) on performance, haematological indices and oxidative stability of chicken meat. A total of 150 Ross 7-day-old chicks were weighed and allotted to five treatments comprising dietary levels of 0 mg VE + 0 mg SE (Control), 100 mg VE + 0.05 mg Se, 200 mg VE + 0.1 mg Se, 300 mg VE + 0.15 mg Se and 400 mg VE + 0.2 mg Se per kg of feed in a completely randomised design. Feed and water were provided ad libitum. The data collected on performance, haematological indices and oxidative stability of meat were subjected to a one-way analysis of variance in a completely randomised design. Performance indices were significantly (p &lt; 0.05) influenced by VE + Se supplementation. Mean daily live-weight gain (48.68 g /bird /day) was highest (p &lt; 0.05) in the 400 mg VE + 0.2 mg group. The mean daily feed intake (g /bird / day) was highest in birds fed the diet containing 200 mg VE + 0.1 mg. The least or best feed conversion ratio (FCR) was observed in the group fed 400 mg VE + 0.2 mg SE. Glutathione peroxidase (GSH-Px) increased as the level of VE + Se increased with the highest activity in 400 mg VE + 0.2 mg Se group. The highest packed cell volume, haemoglobin and red blood cell values were observed in birds fed the diet containing 400 mg VE + 0.20 mg Se. In conclusion, to ensure good performance of the chickens and improved oxidative stability of chicken meat in hot climate, feeding broilers VE + SE at 400 mg VE + 0.2 mg Se is recommended.

OXIDATIVE STABILITY OF CHICKEN MEAT AFTER USE OF OREGANO ESSENTIAL OIL

The purpose of this study was to investigate the effect of oregano essential oil on the oxidation stability of chicken meat. Oregano essential oil was applied in a different way, on the one hand in a feed for broiler chickens and on the other hand on a surface of chicken thighs. The oxidative stability of the chicken meat was investigated in the same way, i.e. 30 minutes after vacuum-packed at room temperature and 6 months after vacuum-packed and storage at -18 °C. The samples of the 1st experiment consisted breast and thigh muscles and skin and of the 2nd experiment thigh muscle and skin. Broiler chickens were fed during the experimental period in the control group with commercial feed mixtures and in the experimental group with similar diets as in the control group but with the addition of 0.05% oregano essential oil. Application of oregano essential oil on surface of thighs was realized 1 ml per 60 g of meat. The impact of oregano essential oil was measured by acid value. Number of acid value 30 minutes after oregano essential oil application in control group was significant higher (6.69 g KOH g -1) than in experimental group (5.39 g KOH g -1). Results of our experiments indicate that the oregano essential oil statistically significant (p 0.05) manifested an impact on the oxidative stability of chicken meat 30 minutes its action. The results impact of oregano essential oil on chicken meat stored at -18 °C for 6 months were comparable to control group, but a tendency to improve oxidative stability was indicated. Feed addition of oregano essential oil did not show any effects on oxidative stability chicken meat.

Effect of Dietary Bacillus coagulans and Different Forms of Zinc on Performance, Intestinal Microbiota, Carcass and Meat Quality of Broiler Chickens.

A total of 288-day-old male broilers were allocated to six dietary treatments to evaluate the effects of zinc source and Bacillus coagulans supplements and their interaction on growth, intestinal microbial population, carcass traits and meat quality in broiler chickens. Three levels of dietary supplemental Zn source (100mg/kg of DM diet zinc oxide, 25 and 50mg/kg of diet zinc oxide nanoparticles (Zn-nan)) and two levels of B. coagulans (0 and 100mg/kg of diet) were combined as a completely randomised design with a 3 × 2 factorial arrangement. B. coagulans increased the body weight gain, body weight and feed conversion ratio. The lactic acid producing bactereia of ileal were increased by B. coagulans supplementation, and its coliform count was decreased by Zn-nan in a dose-dependent manner. The B. coagulans increased the relative weights of legs and proventriculus and reduced weights of livers, abdominal fat and meat thiobarbituric acid (TBA) value. Likewise, dietary B. coagulans increased pH, yellowness and lightness values of leg muscles. Birds fed Zn-nan50 had lower liver weight, TBA and cooking loss and higher yellowness values than chicks fed ZnO-100. In conclusion, the dietary supplementation with B. coagulans improved broiler performance, microbial population and meat quality. The Zn-nan in lower dose could be a good substitution in mineral premix instead of zinc oxide. In addition, the Zn-nan improved intestinal microbial population, carcass characteristics and oxidative stability of chicken meat; however, the combination of two levels of Zn-nan with B. coagulans did not vary the measured parameters.

Mate extract as feed additive for improvement of beef quality

Mate (Ilex paraguariensis A.St.-Hil.) is generally recognized as safe (GRAS status) and has a high content of alkaloids, saponins, and phenolic acids. Addition of mate extract to broilers feed has been shown to increase the oxidative stability of chicken meat, however, its effect on beef quality from animals supplemented with mate extract has not been investigated so far. Addition of extract of mate to a standard maize/soy feed at a level of 0.5, 1.0 or 1.5% w/w to the diet of feedlot for cattle resulted in increased levels of inosine monophosphate, creatine and carnosine in the fresh meat. The content of total conjugated linoleic acid increased in the meat as mate extract concentration was increased in the feed. The tendency to radical formation in meat slurries as quantified by EPR spin-trapping decreased as increasing mate extract addition to feed, especially after storage of the meat, indicating higher oxidative stability. Mate supplementation in the diet did not affect animal performance and carcass characteristics, but meat from these animals was more tender and consequently more accepted by consumers. Mate extract is shown to be a promising additive to feedlot diets for cattle to improve the oxidative stability, nutritive value and sensory quality of beef.

Effect of β-alanine and L-histidine on concentration of carnosine in muscle tissue and oxidative stability of chicken meat

Effect of β-alanine and L-histidine on concentration of carnosine in muscle tissue and oxidative stability of chicken meat

Fatty Acid Profile, Cholesterol and Oxidative Status in Broiler Chicken Breast Muscle Fed Different Dietary Oil Sources and Calcium Levels

The aim of the present study was to evaluate the effects of three feeds containing 6% oils: palm oil (PO), soybean oil (SO) and linseed oil (LO); and three calcium levels (NRC recommendation, 1.25% and 1.50%) on the fatty acid profile, lipid oxidation and cholesterol concentrations of broiler breast meat in a 3 × 3 factorial experiment. A total of 378 one-day-old chicks were randomly assigned to the diets and fed for six weeks. Birds fed diet supplemented with LO, SO and PO had higher proportions of α-linolenic, linoleic and oleic acids, respectively. The LO diet increased the total n-3 fatty acids and decreased the n-6 : n-3 compared with the PO and SO diets. Birds fed the PO diet had higher oxidative stability and cholesterol compared with those fed the SO and LO diets. However, the level of cholesterol in all treatments was within the normal range. The level of calcium and interaction between source of oil and calcium level did not influence lipid oxidation, fatty acid profile and cholesterol level of broiler breast muscle. It can be concluded that dietary LO and SO enhanced n-3 and n-6 polyunsaturated fatty acids, respectively, while dietary PO enhanced the oleic acid and oxidative stability of broiler breast muscle. Thus, this study showed that PO can be used as an alternative oil source in broiler diets with a positive effect on the oxidative stability of chicken meat refrigerated at seven days when compared with vegetable oils that are rich in linoleic and α-linolenic acid.

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.

Chemical characterization, antioxidant activity and application of beetroot and guava residue extracts on the preservation of cooked chicken meat

Agro-industrial activities generate millions of tons of residues all over the world. Although many of them contain bioactive compounds, they are underexplored. Ethanolic extracts of beetroot stems (EEB) and guava pomace (peels, seeds) (EEG) were analyzed to assess their chemical composition (phenolic compounds and chemical profile by GC-MS) and antioxidant activity (EC50 and ABTS). Posteriorly, EEB and EEG were added to processed chicken meat, which was cooked and stored in vacuum and aerobic packages at 4 ± 1 °C for 14 days, to assess their oxidative stability and color. EEB presented higher content of phenolic compounds and antioxidant activity compared to EEG. Using GC-MS, we identified 11 phenolic compounds in EEB and EEG. When added to chicken meat, EEG and EEB retarded lipid oxidation compared to the control after 14 days of storage in aerobic packages. In general, in both packages the natural extracts proved to be as effective as BHT to maintain oxidative stability of chicken meat.

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.

사료 내 홍삼박과 겨우살이 분말 첨가 급여가 육계의 생산성 및 계육의 품질에 미치는 영향

본 시험은 육계에 홍삼박과 겨우살이를 급여하여 5주간 사육한 육계의 생산성과 계육의 일반 성분, 혈액 성상, pH, TBARS, 보수성, 전단력 및 육색을 조사하였다. 실험구는 홍삼박과 겨우살이를 급여하지 않은 처리구를 대조구, 홍삼박 0.5% 급여구는 T1, 홍삼박 1% 급여구는 T2, 겨우살이 0.5% 급여구는 T3, 그리고 겨우살이 1% 급여구를 T4 등 4개 처리구로 나누어 사양하였다. 육계의 생산성은 처리구간 유의적인 변화는 없었고, 폐사율은 대조구보다 홍삼박과 겨우살이 급여구에서 낮아졌다(P<0.05). 계육의 수분, 조단백질 및 조회분 등의 일반 성분은 유의성이 없었으며, 조지방은 홍삼박과 겨우살이 급여구에서 낮았다. 육계의 혈액 성상 중 총 콜레스테롤과 LDL-cholesterol 함량은 대조구보다 홍삼박과 겨우살이 급여구에서 감소하였고, HDL-cholesterol은 증가하였으며, triglyceride와 glucose 함량은 유의한 변화가 없었다. TBARS는 대조구보다 홍삼박과 겨우살이 급여구에서 유의하게 낮아, 육계의 저장성 개선에 도움이되리라 생각된다. 육색은 CIE <TEX>$L^*$</TEX>값과 CIE <TEX>$b^*$</TEX>값은 홍삼박과 겨우살이 급여에 의한 변화는 없었지만, CIE <TEX>$a^*$</TEX>값은 T4에서 증가하였다. 결론적으로 홍삼박과 겨우살이를 급여하면 육계의 폐사율이 낮아지고, 총콜레스테롤과 LDL-cholesterol 함량이 감소하며, HDL-cholesterol이 증가함으로 혈액성상을 개선할 가능성이 있는 것으로 판단된다. The objective of this study was to evaluate the effects of different levels of red ginseng mare or Korean mistletoe powder on growth performance and physicochemical properties of thigh meat in broiler. A total of 200 broiler chicks were divided into five groups were fed a basal diet (control), basal diet supplemented with 0.5% red ginseng mare (T1), red ginseng mare 1% added (T2), Korean mistletoe 0.5% added (T3), Korean mistletoe 0.5% added (T4) for five weeks. Growth performance and proximate composition of chicken thigh meat were not influenced by all treatments, except for mortality and crude fat, which was significantly lower in all treatments with red ginseng mare or Korean mistletoe powder compared to control. Dietary red ginseng mare and Korean mistletoe supplementation had no significantly effects on pH, WHC, shear force, CIE <TEX>$L^*$</TEX>, <TEX>$b^*$</TEX> values, triglyceride and glucose but TBARS values total cholesterol, and LDL-cholesterol were decreased (P<0.05) by the addition red ginseng mare and Korean mistletoe powder. CIE <TEX>$a^*$</TEX> values increased significantly with added red ginseng mare and Korean mistletoe powder relative to the control (P<0.05). It was concluded that the addition of red ginseng mare and Korean mistletoe powder revealed minor improvements in the lipid oxidative stability of chicken meat.

The use of thyme and orange essential oils blend to improve quality traits of marinated chicken meat

Poultry meat contains large quantities of polyunsaturated fatty acids, which lead to oxidative deterioration. Plant essential oils (EO) and natural compounds, with antioxidant properties, may be used to alleviate this problem. Two replications were conducted to evaluate the effects of a mixture (1:1) of thyme and orange oils (EO) on the quality characteristics and the oxidative stability of chicken meat (breast and wing). For each replication, 24 fresh breast fillets and 24 wings were procured from a local grocery store. The EO were added to marinade solution to achieve a final concentration of 0.55% sodium chloride, 0.28% polyphosphate, and 0.05% wt/vol of EO blend. Breasts and wings were split in 2 different groups with homogenous pH and lightness and vacuum tumbled in 2 treatments, a 0.5% EO and a control (CON, no EO). Each group was tested for pH, Commission Internationale d'Eclairage color (lightness, L*; redness, a*; yellowness, b*), moisture content, marinade uptake, purge loss, cook yield, and shear force. Susceptibility to lipid oxidation was determined on fresh and frozen meat by TBA reactive substance analysis (induced oxidation from 0 to 150 min at 37°C). The EO breasts had lower purge loss compared with CON meat. Breast did not show any color, pH, marinade uptake, cooking yield, shear force, or moisture differences due to treatment, although cooked EO breast was slightly less red than CON. The EO wings presented higher a* and b* values after marination and lower purge loss and shear force than CON. No differences were detected on wings for color, pH, marinade uptake, cooking yield, or moisture between EO and CON wings. Both fresh and frozen EO breasts and EO wings were less susceptible to the lipid oxidation during all induced oxidation times compared with CON breasts and wings. In conclusion, EO had a positive effect on broiler breast and wing lipid oxidation without negatively affecting meat quality traits.

Effect of dietary fish oil on n-3 fatty acid content of meat from broiler chickens fed low protein diets

An experiment was carried out to evaluate the effects of dietary fish oil and crude protein (CP) levels on fatty acid composition of the thigh and breast tissues of broiler chickens. Four hundred and fifty, 1-day-old mixed-sex broiler chicks were used in a completely randomised design with factorial arrangement consisting of two dietary CP levels (21 v. 18.0% and 19 v. 17.1% for grower and finisher diets, respectively), and three levels of fish oil inclusion (0, 2 or 4%). Specific increases in eicosapentaenoic acid (EPA, 20 : 5) and docosahexaenoic acid (DHA, 22 : 6) were observed in breast and thigh tissues as a response to increased fish oil supplementation. The n-6 : n-3 fatty acid ratio in breast and thigh meat samples decreased (P &lt; 0.05) in birds fed low protein diets, but dietary protein level led to no alteration in the total n-3 fatty acids of the tissues (P &gt; 0.05). Thigh tissue of chickens fed low protein diets had a higher concentration of DHA (P &lt; 0.05), while the DHA and EPA concentrations in breast tissue were not affected by dietary protein level (P &gt; 0.05). Results of the present study showed that fish oil can be used to fortify EPA and DHA levels in chicken meat and there is an interaction between dietary fatty acids and protein level on meat oxidative stability, and a reduction in dietary protein level may lead to a better oxidative stability of chicken meat.

High dietary concentrations of methionine reduce the selenium content, glutathione peroxidase activity and oxidative stability of chicken meat

Three experiments (EXP) were conducted using two hundred seventy male chicks Ross 308 in each (90 cockerels per treatment; 3 replications, 30 chickens per pen) for 42, 38 and 35 days. The basal diets (treatment 1) for three EXPs contained the identical ingredients, and the concentration of selenium (Se), methionine (Met) and total sulphur amino acids (TSAA) in the control diet was 0.11 mg/kg, 5.65 g per kg and 9.25 g/kg, respectively. Chicks in dietary treatment 2 were fed a basal diet supplemented with 0.3&amp;nbsp;mg/kg of Se (EXP 1, 2 and 3) and in dietary treatment 3 they were fed a basal diet with the addition of 0.3 mg/kg of Se and 1 g/kg (EXP 1 and 2) or 2.5 g/kg of dl-methionine (EXP 3). In EXP 1, sodium selenite and in EXP 2 and 3 Se-enriched yeast were used as sources of supplemental selenium, respectively. The results indicated that the addition of Se or Se and Met into the diet of broilers did not significantly affect the final live weight of chickens and the feed consumption. Moreover, the concentration of Met (P = 0.004), Cys (P&amp;nbsp;= 0.01) and tyrosine (P &amp;lt; 0.001) in breast muscle increased with an increase in dietary Met content, and the isoleucine concentration decreased (P &amp;lt; 0.001). Moreover, the addition of inorganic and organic sources of Se increased the Se content of breast meat (P &amp;lt; 0.001). On the other hand, the addition of Met decreased the concentration of Se (P &amp;lt; 0.001) in breast meat and reduced glutathione peroxidase activity and oxidative stability of raw breast muscle (P = 0.019, P&amp;nbsp;&amp;lt;&amp;nbsp;0.001) and breast meat stored for 3 days (P = 0.016, P&amp;nbsp;=&amp;nbsp;0.006) in EXP 2 and 3.

α-Tocopherol과 Selenium의 첨가 급여가 육계의 생산성 및 닭 다리육의 이화학적 특성에 미치는 영향

본 실험은 <TEX>${\alpha}$</TEX>-tocopherol(0, 50, 100, 200 IU/kg)과 selenium(0.3 ppm) 및 <TEX>${\alpha}$</TEX>-tocopherol 100 IU/kg과 selenium 0.3 ppm을 혼합 급여한 육계의 생산성, 계육의 일반 성분, pH, TBARS, WHC, 전단력, 육색 및 지방산 조성에 미치는 영향을 알아보고자 수행하였다. 육계 360수를 공시하여 대조구와 <TEX>${\alpha}$</TEX>-tocopherol 50 IU/kg 급여구를 T1, <TEX>${\alpha}$</TEX>-tocopherol 100 IU/kg 급여구를 T2, <TEX>${\alpha}$</TEX>-tocopherol 200 IU/kg 급여구를 T3, selenium 0.3 ppm/kg 급여구를 T4, <TEX>${\alpha}$</TEX>-tocopherol 100 IU/kg과 selenium 0.3 ppm/kg 급여구를 T5 등 6개 처리구로 나누어 5주간 사양한 후 다리살 근육을 분석하였다. 육계의 증체량, 사료 섭취량 및 사료 요구율은 처리구간에 유의성이 없었다. 계육의 일반 성분중에 수분과 조단백질, 조회분은 처리구간에 유의성이 없었고, 조지방 함량은 대조구와 T1보다 처리구에서 높았다. pH, 보수성과 전단력은 모든 처리구에서 유의성은 없었다. TBARS는 대조구와 T1은 유의한 차이가 없으나, <TEX>${\alpha}$</TEX>-tocopherol과 selenium 급여구에서 낮았으며, 특히 혼합급여구인 T5에서 TBARS 값이 유의하게 낮았다. 육색중 CIE <TEX>$L^*$</TEX>값과 <TEX>$b^*$</TEX>값은 처리구간에 유의성이 인정되지 않았으나, CIE <TEX>$a^*$</TEX>값은 T2, T3, T5에서 높았다(P<0.05). 지방산의 분석 결과, <TEX>${\alpha}$</TEX>-tocopherol의 급여로 palmitic acid는 감소하고, oleic acid, linileic acid는 증가하여 포화지방산 함량은 줄고, 불포화지방산 함량이 증가하는 결과로 나타났다(P<0.05). 이상의 결과를 종합적으로 고찰해 볼때 <TEX>${\alpha}$</TEX>-tocopherol과 selenium를 육계에 급여하면 육색과 지방의 산화를 억제하는 효과가 있음을 확인할 수 있어 계육의 저장성을 개선할 가능성이 있을 것으로 기대된다. The objective of this study was to evaluate the effects of different levels of <TEX>${\alpha}$</TEX>-tocopherol and selenium in broiler diets on performance and physicochemical properties of chicken thigh meat. A total of 360 broiler chicks divided into six groups were fed a basal diet (control) or basal diet supplemented with 50 IU <TEX>${\alpha}$</TEX>-tocopherol/kg (T1), 100 IU <TEX>${\alpha}$</TEX>-tocopherol/kg (T2), 200IU <TEX>${\alpha}$</TEX>-tocopherol/kg (T3), 0.3 ppm selenium/kg (T4), and 100 IU <TEX>${\alpha}$</TEX>-tocopherol/kg + 0.3 ppm selenium/kg (T5) for five weeks. Growth performance and proximate composition of chicken thigh meat were not influenced by all dietary treatments, except for crude fat, which was significantly lower in the treatment with <TEX>${\alpha}$</TEX>-tocopherol or selenium, or both compared to control. The dietary <TEX>${\alpha}$</TEX>-tocopherol and selenium supplementation had no significant effects on pH, CIE <TEX>$L^*$</TEX> (lightness), and <TEX>$b^*$</TEX> (yellowness) values but TBARS (thiobarbituric acid reactive substance) values were decreased (P<0.05) by the addition of <TEX>${\alpha}$</TEX>-tocopherol and selenium. CIE <TEX>$a^*$</TEX> (redness) values increased significantly with added <TEX>${\alpha}$</TEX>-tocopherol and selenium relative to the control (P<0.05). Likewise, changes in fatty acid composition in chicken thigh meat with the dietary supplementations with <TEX>${\alpha}$</TEX>-tocopherol, selenium and their combination significantly increased (P<0.05) unsaturated fatty acid, whereas saturated fatty acid were decreased. It was concluded that the addition of 200 IU <TEX>${\alpha}$</TEX>-tocopherol (T3) and 100 IU of <TEX>${\alpha}$</TEX>-tocopherol plus 0.3 ppm selenium (T5) were most effectiveness in the improvements in the lipid oxidative stability of chicken meat when compared to the control.

Effect of dietary source of very long chain n-3 polyunsaturated fatty acids in poultry diets on the oxidative stability of chicken meat

Enriching chicken meat with the very long chain n-3 polyunsaturated fatty acids (VLC n-3 PUFA) 20:5 (EPA) and 22:6 (DHA) is a possible means of increasing the human consumption of these essential fatty acids as current levels of intake of these fatty acids are extremely low. However, a potential drawback of increasing the VLC n-3 PUFA content of chicken meat is that the oxidative stability of the meat is reduced. Chicken meat is enriched with VLC n-3 PUFA by the addition of fish oil to the chickens’ diet. It is possible that using alternative dietary sources of VLC n-3 PUFA may increase the oxidative stability of the meat (Mooney et al., 1998). The objective of this experiment was to determine what the source of VLC n-3 PUFA in broilers’ diets had on the oxidative stability of their edible tissues.

Influence of Dietary α-Tocopheryl Acetate Supplementation on Cholesterol Oxidation in Retail Packed Chicken Meat during Refrigerated Storage

This study examined the effect of dietary alpha-tocopheryl acetate on lipid and cholesterol oxidation in retail packed chicken meat during refrigerated storage. Male broiler chicks were randomly assigned to five pens containing 30 chicks each, which was subjected to one of five dietary treatments (0, 50, 100, 200, or 400 IU of alpha-tocopheryl acetate/kg diet). Five different levels of alpha-tocopherol were supplied to the chicks from 3 to 6 weeks. After 42 d of feeding all the broilers were slaughtered, and the carcasses were packed in polyethylene bags individually, bags similar to those used in the retail trade, and stored for 12 d at 4 degrees C. Growth performance and fatty acid composition were not affected by the dietary alpha-tocopherol levels. The alpha-tocopherol content in breast and thigh muscles increased as the level of dietary alpha-tocopherol increased. The supplementation with 200 or 400 IU of alpha-tocopherol was more effective in reducing the level of lipid oxidation (P<0.05) and total cholesterol oxidation products (P<0.05). Therefore, an increase in the dietary alpha-tocopherol level from 200 to 400 IU/kg feed causes major improvements in the oxidative stability of chicken meat during refrigerated storage.