Submitted to: Poultry Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/11/2014
Publication Date: 4/1/2014
Citation: Zhuang, H., Bowker, B.C., Buhr, R.J., Sanchez Brambila, G.Y. 2014. Hot-boning enhances cook yield of boneless skinless chicken thighs. Poultry Science. 93:1553-1560.
Interpretive Summary: Cook yield or cook loss is one of the most commonly measured quality attributes for meat products. Cook yield directly affects profits of further processing products and sensory texture quality of finished products. Boneless skinless chicken thighs are a new deboned poultry product in the retail markets and their market share is rapidly growing in the US. There is no scientific information available concerning the effect of deboning time on cook yield of boneless skinless chicken thigh meat. The objective of this study was to investigate the effects of postmortem deboning time on the cook yield of boneless skinless chicken thighs. Our results show that postmortem time for removal of chicken thighs from bones can significantly affect cook yield of boneless skinless chicken thighs. The cook yield of thighs that are removed from bones before the chilling process is significantly higher than those removed from bones after the chilling process. Further experimental data show that the thigh meat removed before chill is darker than that removed after chill after the meat is stored for 24 h in a refrigerator, and there is no difference between these two samples for cooked meat texture quality. These results suggest that early removal of chicken thighs from chicken carcasses after slaughtering can significantly increase yield of cooked thighs with no detrimental effects on meat color and texture.
Technical Abstract: Three experiments were conducted to evaluate effects of postmortem deboning time on cook yield of boneless skinless chicken thighs. In Experiment 1 (3 replications), chicken thigh meat was separated from bones at 0.45 (hot-bone), 2, and 24 h and trimmed to obtain iliotibialis muscle. The iliotibialis samples were stored in -20oC freezer and cooked directly from a frozen state. Results show that there were significant differences in cook yield of the thigh iliotibialis muscle due to postmortem deboning times. The difference was as large as 7% between the hot-boned samples and 24 h samples. In Experiment 2, fresh boneless skinless chicken thighs, which was deboned at 0.3, 2, and 24 h PM, were used as the raw materials and cooked directly from a fresh state at 24 h PM. Results show that cook yield of the hot-boned boneless skinless thighs was significantly higher than those of the 2h and 24h deboned samples, which did not differ from each other. In Experiment 3 (2 replications), the whole legs were cut from carcass backbone at 0.3, 2 and 24 h PM, and half of thighs were separated from legs and half of them remained in the whole legs for the early cut samples. Whole thighs with bone (bone in) were cooked from fresh. Cook yield as well as color of fresh thigh muscles and Warner-Bratzler (WB) shear force of cooked samples were measured. Results show that cook yield of the whole thighs separated from the backbone prior to chilling was significantly higher than those of the 2h and 24h whole thigh samples, which did not differ from each other. by 24 h PM, fresh hot-cut thighs were darker (with lower L* value and higher a*) than those of the thighs that were either cut up at 2 h PM and aged for 22 h or cut at 24 h PM. There were no differences between the three postmortem cut times for WB shear force. There were no differences between the thighs remaining in the whole legs and the thighs separated from legs for cook yield and WB shear force. These results demonstrate that postmortem deboning time can significantly affect cook yield of boneless skinless chicken thigh products. Removal of chicken thighs from bones after chill reduces the cook yield. The difference in the cook yield may result from just removal of whole chicken legs from carcass backbones.