Search Results (12)

Genetic differences typically cause differences in the structure and function of proteins in meat. The objective of this research was to examine the biochemical characteristics and functional behavior of proteins in fresh composite meat from Thai Ligor hybrid chicken (LC) and commercial broiler chicken (BC). The composite meat samples, which comprise minced breast and thigh without skin from 20 chicken carcasses in a 1:1 (w/w) ratio, were randomly selected for analysis using the completely randomized design (CRD). Results showed that BC meat exhibited higher ultimate pH after 24 h, Ca²⁺-ATPase activity, and trichloroacetic acid (TCA)-soluble peptide content compared to LC meat (p < 0.05). While both meat types showed non-significant differences in reactive sulfhydryl (SH) levels (p > 0.05), LC meat exhibited higher hydrophobicity compared to BC meat (p < 0.05). Differential scanning calorimetry (DSC) analysis revealed a single transition peak in all samples. LC meat exhibited higher thermal stability than BC meat, with transition peaks at 91 °C and 81 °C, respectively, in non-sodium chloride (NaCl) treated samples. Samples treated with 2.5% NaCl exhibited transition peaks around 70 °C for BC and 79 °C for LC. LC meat showed higher storage modulus (G′) and loss modulus (G″) values than BC meat, suggesting a stronger gel-forming tendency. LC meat gels exhibited higher hardness, cohesiveness, gumminess, and chewiness, and a slightly lower pH (6.14 vs. 5.97) compared to BC meat gels (p < 0.05). LC meat gels displayed larger expressible moisture content (p < 0.05), although the value was approximately 6%. Compared to LC meat gels, BC meat gels appeared slightly whiter (p < 0.05). To compare the lipid oxidation of BC and LC meat gels day by day, the thiobarbituric acid reactive substances (TBARS) of gels stored at 4 °C in polyethylene bags were measured on Days 0, 4, and 8. Both BC and LC meat gels showed acceptable lipid oxidation-based rancid off-flavor after short-term storage at 4 °C, with TBARS values below 2 mg malondialdehyde (MDA) equivalent/kg on Day 8. Understanding these variations in biochemical properties and functional behavior can help optimize processing methods and produce meat products of superior quality that meet consumer preferences. Full article

The aim of the research was to determine the possibilities for managing chicken meat (fillet) quality by applying the own-construction (OC) device for electrical stunning. We determined the effects based on selected technological and visual features of fillets, providing a measurable basis for producers to take preventive actions to improve meat quality management practices. The experimental material consisted of fillets from broiler chickens. The process of electrically stunning chickens in a water bath was carried out in Polish industrial conditions using two devices: own-construction (OC) and commercial from a Polish company (PLC). We determined the quality of fresh and stored meat (14 days/4 °C) based on technological characteristics (pH, color, tenderness) and visual assessment (number of small and large hemorrhages, defects). As a result, the use of the own-construction (OC) device compared to the commercial (PLC) one has a beneficial effect on: (1) reducing the number of hemorrhages, (2) increasing the share of high-quality fillet production by approx. 50%, (3) brightening and uniforming the color of fillets, and (4) improving the tenderness of fresh meat and maintaining it during 14 days of storage. The effects of using the OC device are beneficial for meat producers on the market. Full article

Wooden breast myopathy (WBM) is a meat abnormality affecting pectoralis majors (PMs) of fast-growing broiler chickens. WBM-affected PMs exhibited varied meat qualities with increasing WBM severity. Normal PMs (NOR), mild WBM-affected PMs (MIL), moderate WBM-affected PMs (MOD), and severe WBM-affected PMs (SEV) were selected as raw materials. The structure and organization of connective tissue and fibrillar collagen were investigated through immersing with sodium hydroxide solution, Masson trichrome staining, and using an electron microscope. The mechanical strength of intramuscular connective tissue was analyzed via the shear force of samples treated with sodium hydroxide solution. The thermal property and secondary structure of connective tissue were analyzed by differential scanning calorimetry and Fourier transform infrared spectroscopy. The obtained connective tissue was dissolved in a sodium hydroxide solution for the evaluation of the physicochemical properties of proteins, including particle size, molecular weight, surface hydrophobicity, and intrinsic fluorescence. In particular, the particle size was measured using a zeta potential instrument. The molecular weight was analyzed by sodium dodecyl sulfate polyacrylamide gel electrophoresis. The surface hydrophobicity and intrinsic fluorescence were measured by spectroscopy technology. Histologically, macrophage infiltration, myodegeneration and necrosis, regeneration, fibrous connective tissue, and thickened perimysial connective tissue were observed in WBM-affected PMs, especially SEV with fibrosis, including blood vessels. Compared with NOR, WBM led to increased average diameter of the collagen fibrils in perimysial (36.61 nm of NOR to 69.73 nm of SEV) and endomysial (34.19 nm of NOR to 56.93 nm of SEV) layers. A significant increase (p < 0.05) was observed in the mechanical strength (2.05 N to 5.55 N) of fresh PMs and the thermal transition temperature (onset temperature (T_O), 61.53 °C to 67.50 °C; maximum transition temperature (T_M), 66.46 °C to 70.18 °C; termination temperature (T_E), 77.20 °C to 80.88 °C) of connective tissue from NOR to SEV. Cooking decreased the mechanical strength, and MOD samples showed the highest mechanical strength (1.24 N, p < 0.05), followed by SEV (0.96 N), MIL (0.93 N), and NOR (0.72 N). For proteins in connective tissue, random coil (19.64% to 29.61%, p < 0.0001), particle size (p < 0.05), and surface hydrophobicity (p < 0.05) increased with the decrease in the α-helix (14.61% to 11.54%, p < 0.0001), β-sheet (45.71% to 32.80%, p < 0.0001), and intrinsic fluorescence of proteins from NOR to SEV. The molecular weights of intramuscular connective tissue proteins were in the ranges of >270 kDa, 180–270 kDa, 110–180 kDa, 95–100 kDa, and <15 kDa. Taken together, WBM resulted in thickened organization, tightly packed collagen fibrils, increased mechanical strength and thermal temperature, and increased particle size, surface hydrophobicity, and intrinsic fluorescence of proteins in connective tissue, as the WBM severity increased. Full article

This study evaluated the effect of using olive pomace acid oil (OPAO) instead of crude palm oil (PO) or refined olive pomace oil (ROPO) on lipid composition, lipid oxidation, and quality of chicken meat. Broiler chickens were fed diets with 6% of PO, ROPO, or OPAO, and deboned legs with skin were sampled. Fresh and refrigerated (commercial conditions; 7 days) chicken meat samples were assessed for fatty acid (FA) composition, tocopherol (T) and tocotrienol (T3) content, lipid oxidative stability, 2-thiobarbituric acid (TBA) values, volatile compounds, color, and sensory acceptance. Using ROPO and OPAO led to meat richer in monounsaturated FAs and OPAO to lower α-T levels compared to PO. Oxidative stability, TBA values, volatile compounds, and overall acceptance of meat were not affected by diet. Refrigeration increased TBA values and some volatile compounds’ concentrations, but it did not decrease redness or consumers’ overall acceptance. Therefore, the OPAO used was an adequate fat source for chicken diets at 6%, as it produced dark meat lower in saturated FAs than PO without affecting lipid oxidation or overall acceptance. According to this, upcycling OPAO as an energy source in chicken diets would be possible, which can contribute to the sustainability of the food chain. Full article

The objective of the present trial was to evaluate the effects of nettle leaves (Urtica dioica) supplementation, broiler gender and muscle portion on meat fatty acid and mineral profiles. Prior to the trial, a total of 600 one-day-old Cobb 500 broiler chickens of both genders, equally, were randomly divided into three groups: a basal diet (control group) and a basal diet supplemented in the last two weeks of fattening with fresh nettle leaves (30 g/kg diet) or with oven dry nettle leaves (5 g/kg diet). After reaching 42 days of age, twenty birds per diet group were randomly selected (four birds per box, both genders equally) and slaughtered, and breasts and drumsticks were collected for analysis. The dry nettle supplementation increased the MUFA and lowered the PUFA, n-6 and n-6/n-3 ratio, mainly in female broilers (p < 0.05). Drumsticks had higher MUFA and PUFA and lower SFA and n-6/n-3 ratio compared to breast meat (p < 0.05). The addition of nettle to broiler diet increased Fe, Zn and Se and decreased Ca levels, mainly in drumsticks (p < 0.05). Furthermore, drumstick meat had more elements with proven health benefits, such as Fe, Zn, Ca and Mn, than breast meat. This study suggests that feeding Cobb 500 broilers with the addition of nettle leaves can significantly change meat fatty acid and mineral composition, but this effect differed between gender and portion. Full article

Campylobacteriosis is recognized as one of the most common food-borne zoonoses, with worldwide distribution, having undercooked poultry meat and other cross-contaminated foodstuffs as the main sources of human infections. The current study aimed to provide data on the occurrence of the thermophilic Campylobacter spp. in seven broiler chicken flocks, from three north-western Transylvanian counties of Romania, as well as to determine the antimicrobial resistance profile of the isolated C. jejuni strains. A total of 324 fresh cecal samples were collected during the slaughtering process, and screened for the presence of Campylobacter spp., using routine microbiological and molecular diagnostic tools. Overall, 85.2% (276/324; 95% CI 80.9–88.6) of the tested samples expressed positive results for Campylobacter spp., with dominant occurrence of C. coli towards C. jejuni (63.4% vs. 36.6%). From the six tested antimicrobials, the 101 isolated C. jejuni strains were resistant against ciprofloxacin (79.2%), nalidixic acid (78.2%), tetracycline (49.5%), and streptomycin (7.9%), but total susceptibility was noticed against erythromycin and gentamicin. Seven (6.9%) isolates exhibited multidrug resistance. The study results emphasize the role of broiler chicken as reservoir of Campylobacter infections for humans, as well as strengthen the necessity of the prudent using of antimicrobials in the poultry industry. Full article

The physicochemical characteristics and flavor-related compounds of thigh meat derived from diverse Korean native chickens (KNC), namely Hanhyup No. 3 (HH3), Woorimatdag No 1 (WRMD 1), and Woorimatdag No 2 (WRMD 2), under fresh and frozen-thawed conditions were studied and compared with those of commercial broilers (CB). Regardless of the breed, KNC showed a higher (p < 0.05) percentage of linoleic and arachidonic acid. The highest proportion of docosahexaenoic acid was observed in WRMD 2. Despite having a higher collagen content, thigh meat derived from KNC maintained a similar texture profile in comparison to that of CB. The concentrations of most free amino acids (FAA), except for taurine, tryptophan, and carnosine, were higher in frozen-thawed meat than in fresh meat. Regarding volatile organic compounds (VOC), following freezing, the concentration of favorable VOCs increased in CB, but decreased in WRMD 1, suggesting a loss of pleasant flavor in frozen-thawed meat. This study indicated that changes in VOCs, including hydrocarbons (d-limonene, heptadecane, hexadecane, naphthalene, pentadecane, 3-methyl-, tridecane), esters (arsenous acid, tris(trimethylsilyl) ester, decanoic acid, ethyl ester, hexadecanoic acid, ethyl ester), alcohol (1-hexanol, 2-ethyl-), ketones (5,9-undecadien-2-one, 6,10-dimethyl-), and aldehydes (pentadecanal-, tetradecanal, tridecanal), may be a promising marker for distinguishing between fresh and frozen-thawed chicken thigh meat. These findings are of critical importance as preliminary data for developing high-quality chicken meat products. Full article

Poultry meat is considered the most important source of Campylobacter spp. Because of rising antimicrobial resistance in Campylobacter spp., this study investigated the antimicrobial resistance of Campylobacter isolates from fresh broiler chicken meat originating from the Baltic countries sold in Estonian retail settings. Additionally, human clinical isolates obtained from patients with Campylobacter enteritis in Estonia were analysed. The aim of this study was to investigate the susceptibility of Campylobacter spp. to nalidixic acid, ciprofloxacin, tetracycline, streptomycin, erythromycin and gentamicin. The broth microdilution method with the EUCAMP2 panel was used for MIC determination and antimicrobial mechanisms were analysed using WGS data. A total of 46 Campylobacter strains were analysed, of which 26 (42.6%) originated from Lithuanian, 16 (26.2%) from Latvian, and 4 (6.6%) from Estonian fresh broiler chicken meat. In addition, 15 (24.6%) Campylobacter strains of patients with campylobacteriosis were tested. The antimicrobial resistance patterns of Campylobacter spp. isolated from fresh broiler chicken meat samples of Estonian, Latvian and Lithuanian origin collected in Estonian retail, and from patients with Campylobacter enteric infections, were determined. A total of 46 (75%) of the isolates tested were C. jejuni and 15 (25%) were C. coli. Campylobacter resistance was highest to nalidixic acid (90.2% of strains) and ciprofloxacin (90.2%), followed by tetracycline (57.4%), streptomycin (42.6%) and erythromycin (6.6%). All strains were sensitive to gentamicin. Additionally, antimicrobial resistance genes and point mutations were detected in 27 C. jejuni and 8 C. coli isolates previously assigned as resistant with the phenotypic method. A high antibiotic resistance of Campylobacter spp. in Lithuanian- and Latvian-origin broiler chicken meat and Estonian clinical isolates was found. Similar antibiotic resistance patterns were found for broiler chicken meat and human Campylobacter isolates. Full article

This study aimed to evaluate the effects of aging on the quality of breast meat from broilers affected of wooden breast. Samples that were classified as normal (control), moderate (hardness verified only in one region of breast fillet), and severe (hardness verified in all the extension of breast fillet) were evaluated fresh and after three and seven days of aging. Normal samples and samples with a moderate degree of myopathy showed greater water-holding capacity, which may benefit the processing industry of poultry meat. During the aging process, increase was observed in total collagen concentration (from 0.41% in normal samples to 0.56% in samples with severe degree). Samples of chicken breast affected by moderate degree showed higher myofibril fragmentation index (MFI = 115) than normal chicken samples (95.65). Although chicken samples affected with severe degree of wooden breast myopathy are more tender than normal chicken breasts, they produce more exudate, which can be detrimental to the processing of poultry meat. The aging process may improve the reduction of cooking weight loss and protein loss in exudation of broilers’ breasts affected by wooden breast myopathy. Full article

The aim of this study was to examine the effects of storage on the quality of sausages made with breast from chickens affected by wooden breast myopathy (WBM). Breast samples from male broilers slaughtered at 48 days old were used. Normal (absence of myopathy), moderate degree (hardness only in one region of the breast) and severe degree samples (hardness over the entire length of the breast) were processed into sausages and evaluated prior to storage and after being vacuum-packed and stored for 7, 14, 21 and 28 days at 4 °C. There was a decrease (p < 0.001) in pH and an increase (p < 0.001) in cooking weight loss in samples of sausages, regardless of the myopathy, after 28 days of storage. Sausages produced with chicken breast samples affected by wooden breast myopathy presented higher (p < 0.0001) moisture concentration (72% for the severe degree) and higher (p = 0.0224) protein concentration (17.27% and 17.36%, respectively, for the moderate and severe degrees) than sausages made of normal samples (70.72% and 14.32%, respectively). The results indicate that sausages produced with meat from birds moderately and severely affected by the myopathy show higher oxidative stability. Fresh sausages produced with breast meat from birds affected by wooden breast syndrome may be stored (4 °C) for up to 28 days without exhibiting the characteristic rancid taste and smell. In sensory analysis, no differences were observed between the formulations, which suggests that the consumers approved the samples regardless of the disease severity in the meat used for the making of the sausages. The current results show that chicken meat affected by wooden breast myopathy can be used for producing fresh sausages in the industry. Full article

We assessed the concentrations of Fe, Cu, Zn, Mn, Se, Co, Cr, Pb, Cd, and Ni in chicken meat and meat products, feed, and litter, as well as laying hens’ eggs, feed and litter to monitor the quality of products on the market and their safety for human consumption as judged by recommended daily allowance (RDA) and tolerable upper levels. Samples were chosen as the most popular poultry products in Saudi Arabia. A total of 45 broiler samples of frozen or fresh meat, liver, burger, or frankfurter were chosen from the same brand. Additionally, 60 table eggs from four commercial brands were collected, and the edible parts of these were used to determine levels of minerals and toxic elements. Furthermore, 30 feed and litter samples were collected from the starter, grower, and layer diets of broilers and laying hens. The results indicated that there were significant levels of most of the trace elements and heavy metals in the different meat sources. Furthermore, the liver contained the highest levels of elements, except for Cr, Co, and Ni. The highest Cr level was detected in the fresh meat, followed by frozen meat. Trace elements (Mn and Co) and heavy metals (Ni and Pb) were not detected in either the frozen or the fresh meat. The chicken burger and the frankfurter exhibited similar trace-element and heavy-metal contents, except for Zn and Mn, as the frankfurter showed higher concentrations than the burger. Differences in most of the trace and toxic elements among the different sources of eggs were not found to be significant, except for Zn. Differences between the broiler meat and table eggs were only substantial for Fe and Zn. Fe was significantly higher in meat than in eggs, and the opposite trend was found for Zn. The liver contained higher heavy metals than the eggs, except for Cr. In addition, the burger had higher concentrations of essential (Cu and Co) and heavy metals (Pb and Ni) than the eggs but had lower levels of Zn and Cr. The frankfurter exhibited significantly higher levels of Fe, Cu, Mn, Co, Pb, and Ni than the eggs but lower levels of Zn and Cr. To summarize, Cd, Pb, As, and Se were not detected in the broiler meat or eggs, indicating no risks from these toxic elements. Conversely, the liver exhibited the highest content of heavy metals, except for Cr, indicating that the intake of Pb and Cd was above the recommended daily allowance (RDA) for adults. The meat products exhibited higher Pb, Cd, and Ni levels than the broiler meat and the table eggs, suggesting that they posed a health threat to humans, and the intake of Pb in the meat products was higher than the RDA. Thus, chicken meat and table eggs, which are primary protein sources, are safe sources of human nutrition, while liver and meat products may present potential health hazards through the food chain. Full article

This study compares between different selenium forms (sodium selenite; SeS, selenomethionine; Met-Se or nano-Se) and levels on growth performance, Se retention, antioxidative potential of fresh and frozen meat, and genes related to oxidative stress in Ross broilers. Birds (n = 450) were randomly divided into nine experimental groups with five replicates in each and were fed diets supplemented with 0.3, 0.45, and 0.6 mg Se/kg as (SeS, Met-Se), or nano-Se. For overall growth performance, dietary inclusion of Met-Se or nano-Se significantly increased (p < 0.05) body weight gain and improved the feed conversion ratio of Ross broiler chicks at the level of 0.45 and 0.6 mg/kg when compared with the group fed the same level of SeS. Se sources and levels significantly affected (p < 0.05) its concentrations in breast muscle, liver, and serum. Moreover, Se retention in muscle was higher (p < 0.05) after feeding of broiler chicks on a diet supplemented with Met-Se or nano-Se compared to the SeS group, especially at 0.6 mg/kg. Additionally, higher dietary levels from Met-Se or nano-Se significantly reduced oxidative changes in breast and thigh meat in the fresh state and after a four-week storage period and increased muscular pH after 24 h of slaughter. Also, broiler’s meat in the Met-Se and nano-Se groups showed cooking loss and lower drip compared to the SeS group (p < 0.05). In the liver, the mRNA expression levels of glutathione peroxidase, superoxide dismutase, and catalase were elevated by increasing dietary Se levels from Met-Se and nano-Se groups up to 0.6 mg/kg when compared with SeS. Therefore, dietary supplementation with 0.6 mg/kg Met-Se and nano-Se improved growth performance and were more efficiently retained than with SeS. Both sources of selenium (Met-Se and nano-Se) downregulated the oxidation processes of meat during the first four weeks of frozen storage, especially in thigh meat, compared with an inorganic source. Finally, dietary supplementation of Met-Se and nano-Se produced acceptable Se levels in chicken meat offered for consumers. Full article