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Only a few years ago, the poultry industry began to face a recent abnormality in breast meat, known as wooden breast, which frequently overlaps with white striping. This study aimed to assess the impact of wooden breast abnormality on quality traits of meat. For this purpose, 32 normal (NRM), 32 wooden (WB), and 32 wooden and white-striped (WB/WS) Pectoralis major muscles were selected from the same flock of heavy broilers (males, Ross 708, weighing around 3.7 kg) in the deboning area of a commercial processing plant at 3 h postmortem and used to assess histology, proximate (moisture, protein, fat, ash, and collagen) and mineral composition (Mg, K, P, Na and Ca), sarcoplasmic and myofibrillar protein patterns, and technological traits of breast meat. Compared to the normal group, WB/WS fillets showed more severe histological lesions characterized by fiber degeneration, fibrosis, and lipidosis, coupled with a significantly harder texture. With regard to proximate and mineral composition, abnormal samples exhibited significantly (P < 0.001) higher moisture, fat, and collagen contents coupled with lower (P < 0.001) amounts of protein and ash. Furthermore, increased calcium (131 vs. 84 mg kg(-1); P < 0.05) and sodium (741 vs. 393 mg kg(-1); P < 0.001) levels were found in WB/WS meat samples. The SDS-PAGE analysis revealed a significantly lower amount of calcium-ATPase (SERCA, 114 kDa), responsible for the translocation of Ca ions across the membrane, in normal breasts compared to abnormal ones. As for meat quality traits, fillets affected by wooden abnormality exhibited significantly (P < 0.001) higher ultimate pH and lower water-holding/water-binding capacity. In particular, compared to normal, abnormal samples showed reduced marinade uptake coupled with increased drip loss and cooking losses as well. In conclusion, this study revealed that meat affected by wooden breast or both wooden breast and white striping abnormalities exhibit poorer nutritional value, harder texture, and impaired water-holding capacity.

One of the consequences of intense genetic selection for growth of poultry is the recent appearance of abnormalities in chicken breast muscles, such as white striping (characterised by superficial white striations) and wooden breast (characterised by pale and bulged areas with substantial hardness). The aim of this study was to evaluate the quality traits of chicken fillets affected by white striping and wooden breast abnormalities. In two replications, 192 fillets were divided into the following four classes: normal (n = 48; absence of any visual defects), white striping (n = 48, presence of white striations), wooden breast (n = 48; diffusely presence of hardened areas) and white striping/wooden breast (n = 48; fillets affected by both abnormalities). Morphology, raw meat texture and technological properties were assessed in both unprocessed (pH, colour, drip loss, cooking loss and cooked meat shear force) and marinated meat (marinade uptake, purge loss, cooking loss and cooked meat shear force). Fillets affected by white striping, wooden breast or both abnormalities exhibited higher breast weights compared with normal fillets (305.5, 298.7, 318.3 and 244.7 g, respectively; P < 0.001). Wooden breast, either alone or in combination with white striping, was associated with a significant ( P < 0.001) increase of fillet thickness in the caudal area and raw meat hardness compared with both normal and the white striping abnormality, for which there was no difference. Overall, the occurrence of the individual and combined white striping and wooden breast abnormalities resulted in substantial reduction in the quality of breast meat, although these abnormalities are associated with distinct characteristics. Wooden breast fillets showed lower marinade uptake and higher cooking losses than white-striped fillets for both unprocessed and marinated meats. On the other hand, white-striped fillets showed a moderate decline in marinade and cooking yield. Fillets affected by both abnormalities had the highest ( P < 0.001) ultimate pH values. In contrast, the effects on colour of raw and cooked meat, drip loss, purge loss and cooked meat shear force were negligible or relatively low and of little practical importance. Thus, the presence of white striping and wooden breast abnormalities impair not only breast meat appearance but also the quality of both raw and marinated meats mainly by reducing water holding/binding abilities.

The aims of this study were to evaluate the incidence of white striping (WS) under commercial conditions and assess its effect on some quality traits in broiler breast fillets. In the first experiment, occurrence of WS (absence = normal; presence classified in 2 levels as moderate or severe) was assessed in a major commercial processing plant on 28,000 breast fillets (pectoralis major muscles) chosen at random from 56 flocks of broilers processed at 45 to 54 d of age. In the second experiment, 153 fillets were selected based on WS degree (normal, moderate, or severe) and used to assess ultimate pH, color, drip loss, cook loss, and Allo-Kramer-shear force on raw meat as well to determine marinade uptake, purge loss, cook loss, total yield, and Allo-Kramer-shear force after tumbling with a 15% (wt/wt) solution containing sodium tripolyphosphate (2.3%) and sodium chloride (7.6%). The total incidence of white striped breast fillets was 12.0% (8.9 and 3.1% in moderate and severe degree, respectively). Considering the effect of genotype, high-breast yield hybrids exhibited a higher overall incidence of WS compared with standard breast yield birds (15.2 vs. 10.0%; P ≤ 0.001). Severe fillets showed higher pH than moderate and normal groups (5.95 vs. 5.88 and 5.86; P ≤ 0.05). Fillets with severe and moderate WS also exhibited lower marinade uptake compared with normal fillets (7.92 vs. 10.97 vs. 12.67%; P ≤ 0.05). Moreover, cook losses increased as the degree of WS increased from normal to severe groups in both raw (21.27 vs. 23.20 vs. 26.74%; P ≤ 0.05) and marinated meat (14.59 and 14.84 vs. 15.93%; P ≤ 0.05). Finally, nonmarinated fillets with severe striping had lower Allo-Kramer-shear force compared with moderate and normal ones (3.69 vs. 4.41 and 4.91 kg/g; P ≤ 0.05). In conclusion, this study revealed the importance achieved by WS defects in the production of broiler meat as well as its very negative impact on water holding and binding capacity of breast meat.

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