Date of Graduation

12-2013

Document Type

Dissertation

Degree Name

Doctor of Philosophy in Poultry Science (PhD)

Degree Level

Graduate

Department

Poultry Science

Advisor

Casey M. Owens

Committee Member

Jason K. Apple

Second Committee Member

Keith Bramwell

Third Committee Member

L. C. Cavitt

Keywords

Biological sciences; Broiler; Fillet; Meat quality; Tenderness

Abstract

Market trends have dictated that broilers be reared for divergent market demands for decades. Also, broiler genetic strains have been adapted to meet market demands which include: genetic selection for improved breast meat, the practice of growing birds to older ages and greater market weights to meet demands, and decreasing postmortem (PM) aging time to improve processing efficiency and fillet yield. These production practices can also affect product quality, specifically boneless breast fillet tenderness and water-holding capacity. To address these factors, a series of experiments were conducted to determine the effect of strain and slaughter age on meat quality parameters, as well as potential causes of these differences in meat quality. Furthermore, commonly accepted methods for improving boneless breast fillet meat quality were evaluated for the effect of older slaughter age and greater market weights. Based on these results, it appears that, regardless of debone time, broilers reared to greater market weights are tougher than birds reared to a lighter market weight. There are several factors that are compounding this increased toughness, including slower progression of rigor development, greater myofibrillar diameter, and perhaps decreased PM fragmentation; however, the relationship among factors is not fully exploited. Also, it appears that boneless breast fillet marination is critical in these larger birds to alleviate the toughness associated with pre-rigor debone, and may be necessary even when birds are deboned at 24 h PM. Therefore, based on these results it can be recommended that longer PM aging prior to debone is necessary when birds are slaughtered at heavier market weights, and aging the meat off the bone may be beneficial to improving boneless breast fillet tenderness. Furthermore, the commercial practice of tumble-marinating is effective for breast fillets of greater size and may be necessary to avoid negative consumer perception of tenderness.

Share

COinS