Abstract
Heat stress is a broiler welfare issue and economic deficit to the broiler industry. Water atomizing with three-dimensional forced ventilation, a holding treatment after summer transport for broiler, has been proved to significantly improve water holding capacity of fresh meat. However, effectiveness of this treatment on water retention after freeze-thaw needs to be conducted. Therefore, the objective of this study was to assess whether water atomizing with forced ventilation could increase freeze-thaw meat quality after birds slaughtering. Arbor Acres broiler (n = 105), undergoing 32°C ambient temperature transport, was randomly categorized into 3 treatments: 1) T group, which underwent 45-min transport without rest; 2) TR group, which underwent 45-min transport with 1-h rest; and the 3) TWFR group, which underwent 45-min transport followed by 15-min water atomizing with three-dimensional forced ventilation and 45-min rest. All birds were hot-deboned within 30-min postmortem. A total of 105 breast fillets were collected and split into halves, which left part fillets were kept in 4°C and for meat analysis, the other part fillets, marked with T-F, TR-F, and TWFR-F, were frozen (-18°C) for 1 mo and then thawed overnight for meat quality analysis. Regardless of fresh or frozen treatment among 3 groups, TWFR has the highest pH which was more than 6.01 (P < 0.05). The L* value, drip loss, and cooking loss of TWFR were significantly lower compared to T and TR groups in both fresh and frozen breast fillets (P < 0.05). Compared with the T group, the TWFR meat shows closely microscopic structure which means less water loss channel. The impedance amplitude of the fresh meat was significantly higher than that of the frozen-thawing meat (P < 0.05). TWFR-treated meat has significantly higher impedance module than T and TR meat at 50 Hz frequency region, for both fresh or thawed meat. Among 6 treatments, TWFR fresh meat has significantly highest Q (modulus change ratio) value (P < 0.05). These results indicate that TWFR treatment for 15 min after transport can improve meat quality, which may be due to the improved welfare of broilers transported in hot summer months.