Changes in protein fractions of chicken breast meat affected by white striping

White striping striations parallel to muscle fibres direction have been recently observed on the surface of chicken breast which could be ascribed to intensive growth genetic selection. The aim of this study was to evaluate the effect of white striping on protein fractions of chicken breast fillets. Twelve Pectoralis major muscles for both normal and white striping fillets were used to evaluate collagen content (colorimetric method) as well as quantity (Bradford method) and solubility of myofibrillar and sarcoplasmic protein fractions together with water holding capacity of the meat (cooking loss). Pattern of molecular weight protein profile by SDS-PAGE analysis was also assessed. White striped fillets exhibited higher collagen content (1.36 vs. 1.22%; P<0.01) and lower amount of myofibrillar (8.7 vs. 14.0%; P<0.05) and sarcoplasmic (2.6 vs. 3.2%; P<0.001) protein fractions in comparison to normal fillets. White striping defect also resulted in a dramatic decline of total, sarcoplasmic and myofibrillar protein solubility which resulted in a significant increase in cooking loss (33.7 vs. 27.4%; P<0.001). SDS-PAGE analysis evidenced a strong reduction of almost all sarcoplasmic and some major myofibrillar (actin, slow twitch light chain myosin and fast-twitch light chain myosin) proteins. In conclusion, this study revealed that white striping had great detrimental impact on protein profile of chicken breast meat.