Muscle water properties in raw intact broiler breast fillets with the woody breast condition

The purpose of this study was to investigate the relationships between muscle water properties, water-holding capacity (WHC), and woody breast (WB) severity in intact raw broiler breast fillets. Broiler pectoralis major deboned at 3 h postmortem was collected from a commercial plant and categorized as normal (NORM), moderate WB, or severe WB (SEV). Meat drip loss was calculated based on weight loss during overnight storage at 4°C. Water properties of the intact fillets were determined with time domain nuclear magnetic resonance and the T₂ relaxation times were determined using an inverse Laplace algorithm (CONTIN). Three T₂ water components, hydration water (T_2b), intra-myofibrillar water (T₂₁), and extra-myofibrillar water (T₂₂), were identified. With increasing WB severity, the time constant of each water component and the relative content of T₂₂ (P₂₂) increased while the relative areas of T_2b and T₂₁ (P_2b and P₂₁, respectively) decreased. Spearman correlation analysis showed that there were significant correlations between the WB condition score and either the time constant or normalized area for each T₂ component. T₂₂ normalized areas (A₂₂) were most strongly correlated with the WB score (r = 0.75); however, the weakest correlation was found between the WB score and T₂₁ areas (A₂₁). Pearson correlation analysis revealed that the strongest correlation (r = 0.64) was found between A₂₂ and drip loss; however, there was no correlation between A₂₁ and drip loss. Within the NORM group, drip loss was significantly correlated to the time constants for both T_2b and T₂₁. Within the SEV group, only A₂₂ was significantly correlated to drip loss. These data indicate that the WB condition has a significant impact on the distribution of water within the intact muscle tissue. The content of extra-myofibrillar water in broiler breast fillets may be a key factor responsible for the poor WHC measurements in WB meat.