Submitted to: Poultry Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: November 15, 2000
Publication Date: N/A
Interpretive Summary: Many poultry companies grow young chickens (broilers) to various ages prior to processing. This age range can vary from 5 to 8 weeks, so the size of the birds and the resulting meat harvested also varies. Another reality that processors deal with is the time necessary to ensure optimum texture in the cooked breast meat. This is a critical issue that has significant economical impact. The longer time that carcasses are held in storage after processing, the more tender the resulting cooked meat. However, this "aging" time is expensive due to cooler and labor costs. In this study we wanted to determine the effects of bird age at slaughter and the "aging" time on some quality issues. Results indicate that cook yield and tenderness changed as the birds got older, and that the longer carcasses were "aged", the more tender the cooked meat. These results are important for processors because they indicate that breast meat from younger birds can be removed from the carcasses sooner, saving cooler and labor costs without sacrificing tenderness of the cooked meat.
Breast fillet quality was evaluated from 37, 39, 42, 44, 46, 49, and 51- d-old broilers after post chill (PC) aging on the carcass 0, 2, 4, or 6 h and deboning. Fillets were vacuum sealed in cooking bags, and heated to an internal temperature of 72 C by submersion in a 95 C water bath. Cook yield was determined as the weight percentage of the fillet remaining after cooking. Texture of the cooked fillets was measured using a Warner-Bratzler (W-B) shear device. Fillet cook yield and shear force values were significantly affected by bird age at slaughter, and PC carcass aging duration before deboning. Bird gender significantly affected cook yield, while the interaction between age and PC aging duration significantly affected W-B shear. Fluid lost during cooking was greater for fillets aged 0 h PC and decreased when PC aging was 2 h or greater. Overall, W-B shear values decreased (more tender) when fillets were aged on the carcass at least 2 h PC, with the exception of fillets from 51-d-old broilers. After 2 h of PC aging on the carcass, shear force values for fillets from older broilers (49 and 51 d-old) were in the "very tough" portion of a texture scale (> 12.60 kg), while texture of fillets from 42 and 44 d-old broilers were in the "slightly tough to slightly tender" portion of the scale (8.5 and 7.2 kg, respectively). These data show that if poultry processors are harvesting fillets earlier than usual (<2 h PC aging), the fillet texture will be more tender if it originates from younger broilers (42 or 44 d-old) instead of older broilers (49 or 51 d-old).