Effect of freezing on the quality of breast meat from broilers affected by wooden breast myopathy.

The objective of the present study was to characterize possible variations in the quality of wooden chicken breast meat during freezing for 12 mo, in order to prove whether the shelf life recommended by the industry allows the storage of that type of meat without compromising its consumption. Three hundred samples of male Cobb 500 broilers slaughtered at 42 d of age were used. Part of the samples (n = 20 normal-control group; n = 20 moderate degree; n = 20 severe degree) were analyzed on the day of collection (beginning), previously kept under refrigeration (4°C). The other samples were stored (-18°C) for up to 12 mo. At the end of each proposed freezing period (3, 6, 9, and 12 mo), physical and chemical analyses were performed (per period: n = 20 normal-control group; n = 20 moderate degree; n = 20 severe degree). Color (L*, a*, and b*), pH, water-holding capacity, cooking losses, tenderness, lipid oxidation, chemical composition, cholesterol concentration, mineral profile, and collagen concentration were evaluated. The physicochemical quality of wooden chicken breast meat is significantly altered during frozen storage for 12 mo, being of inferior quality when compared to normal chicken breast meat, which can negatively affect consumer acceptance. However, it should be noted that even after 12 mo of freezing, the meats did not show oxidative rancidity.

Research Note: Quality parameters of turkey hens breast fillets detected in processing plant with deep pectoral myopathy and white striping anomaly.

The increase in the consumption of poultry meat intensified production, which allowed the emergence of myopathies associated with broiler and turkey meat. The aim to examine possible quality alterations in the 240 Pectoralis major muscle (breast fillets) from carcasses of turkey breeder hens. Regarding DPM, 120 samples of breast fillets from turkey of the Nicholas strain with Pectoralis minor muscle together were selected according to the occurrence of the myopathy in the Pectoralis minor muscle (tender), as follows: DPM score 2 (n = 40), DPM score 3 (n = 40), and a control group unaffected by DPM, score 0 (n = 40). Then, different 120 samples, from the same flock of birds, were selected according to White Striping (WS) anomaly in the Pectoralis major muscle (breast fillets), considering the degree of severity of the striations apparent in the muscle, as follows: moderate (n = 40), severe (n = 40) and a control group (normal) without the presence of WS anomaly (n = 40), with set up as a completely randomized design with 3 treatments for DPM and WS. We evaluated in meat of turkey breeder hens color, water-holding capacity (WHC), cooking loss (CL), shear force (SF), sarcomere length (SL) and total, soluble and insoluble collagen contents. The color parameters lightness (L*), redness (a*), and yellowness (b*) of turkey breeder hens breast fillets were altered by the occurrence of DPM and WS and as except CL, there were a difference for WHC and SF (P < 0.05). Significant differences were observed for sarcomere length (P < 0.05) between fillets without myopathies and with DPM Score 2 and 3 too. Higher values of total collagen (%) were observed for the most severe category of involvement for both myopathies. The DPM and WS affect the color and in a partial reduction texture of the breast fillets meat of turkey breeder hens and this may have a negative economic impact on the meat industry, because these are the main points evaluated by the consumer, in the most value commercial cut.

Effect of Aging on the Quality of Breast Meat from Broilers Affected by Wooden Breast Myopathy.

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.

Effects of Storage on Quality Traits of Sausages Made with Chicken Breast Meat Affected by Wooden Breast.

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.

Physical, Chemical and Histological Characterization of Pectoralis major Muscle of Broilers Affected by Wooden Breast Myopathy.

This study aimed to characterize the effects of wooden breast myopathy (WBM) on quality of broiler chicken breast meat. Normal samples (absence of myopathy), moderate-degree samples (hardness only in one area of the breast fillet) and severe-degree samples (hardness throughout the breast fillet) were classified. In macroscopic analysis, the pectoral muscle affected by the WBM showed, in general, pale color with stiff, irregular and reddish regions (suffusions and petechiae), with the presence of white striations. In microscopic analysis, the myopathy was characterized by loss of the polygonal aspect of the muscle fibers. Samples with moderate degree of the myopathy showed greater (p = 0.0266) water retention capacity. There was an increase (p = 0.004) in total collagen concentration in samples from the severe-degree group 0.29% in normal samples to 0.43 and 0.48% in samples from moderate- and severe-degree groups, respectively. Samples of chicken breast affected by the severe-degree WBM showed lower (p < 0.0001) myofibrillar fragmentation index (64.51) and lower (p = 0.0002) fat concentration (2.17%) than normal chicken samples (80.45 and 3.79%, respectively). Samples affected by WBM are larger and heavier and present poorer physical quality when compared to normal chicken meat. Histologically it is possible to observe loss of the polygonal aspect of muscle fibers.

Physicochemical Properties and Consumer Acceptance of Hamburgers Processed with Chicken Meat Affected by Wooden Breast Myopathy.

Considering the increased incidence of wooden breast myopathy in broilers, the intake involves no threat to human health, indefinite etiology consumer rejection by appearance in such breasts, and the lack of studies on the industrial use of wooden breast. The objective of this study was evaluating the quality of hamburgers made with chicken meat affected by wooden breast. Breast samples from 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 (hardness over the entire length of the breast) samples were processed for the manufacture of hamburgers whose quality analyses (color, pH, cooking weight loss, shrinkage percentage, tenderness, storage weight loss, water activity, lipid oxidation, chemical composition and consumer test) were performed on non-stored samples (Day 0), and after storing at 30, 60, 90 and 120 days at -20 °C. There was a reduction (p < 0.05) in tenderness in samples of moderate-grade hamburgers (from 161.45 N to 289.40 N) after 120 days of storage. Hamburgers produced with chicken breast samples affected by wooden breast myopathy presented higher (p < 0.0001) fat concentration (5.32 g/100 g and 5.26 g/100 g, respectively, for the moderate and severe degree) than hamburgers made of normal samples (4.45 g/100 g). Lipid oxidation values increased, which exceeded the limit of rancidity detection, independent of myopathy. The consumers equally appreciated the aroma, flavor, and texture, and rated their overall acceptance as similar regardless of the quality of chicken meat. Chicken breast hamburgers with wooden breast myopathy is a viable alternative for the poultry industry.

Efeito do congelamento sobre variáveis relacionadas à cor e à maciez da carne de frangos acometidos pela miopatia “Peito de Madeira” / Effect of freezing on the variables related to color and tenderness of meat from broilers affected by Wooden Breast myopathy

O estudo foi realizado com o objetivo de avaliar os efeitos dos diferentes graus de severidade da miopatia “Peito de Madeira” (moderado e severo) sobre a qualidade da carne de frango, logo após o abate e após congelamento por três meses, uma vez que o prazo de validade determinado pela indústria para carne de frango congelada é de até 12 meses, de modo a comprovar se há possibilidade de armazenar esse tipo de carne sem que ocorram alterações que comprometam o consumo seguro, além de alterações de aparência, suculência e maciez. Foram realizadas análises de cor (L*, a* e b*), perda de peso por cozimento (PPC) e força de cisalhamento (FC). Com o aumento do grau de severidade da miopatia em peitos de frango, observou-se diferenças significativas para as variáveis de cor, aumento de PPC e diminuição da FC, antes e após o congelamento.