Quiz Five

Describe wooden breast and white striping Myopathies in poultry and their impact on meat quality.

There has been a large push towards the consumption of poultry in recent years. This can attributed to many things, one of which is the low cost associated with a increase in the protein provided. To continue to make a profitable product while still charging low costs, the poultry industry has strived to increase the growth of each chicken. Through selective breeding this has been feasible. There have been some negative side effects associated with this rapid growth. Two of those side effects are white striping and wooden breast.

White striping myopathies is defined as white striations running parallel to the muscle on a chicken breast due to chronic myopathic lesions (1). The amount in which these striations are present can range from normal to severe (1). The more severe in which the striations appear, the lower of quality the breast is going to be to consumers. It has been studied that there is a positive correlation between bird size and white striping (1). Not only does white striping cause visual defects that would deter consumers from buying that products, there are also functional defects associated with white striping. For example, it has been shown that in meat with increased white striping there was been a decrease in the meat's ability to hold water (2). The ability to hold water drastically reduces the uses available to the chicken cuts.

Wooden breasts is another quality defect that is occurring more frequently in chicken breasts. Wooden breast is defined as the cut of poultry having hard, pale, and bulged areas (3). It has been found that in many cases where white striping is found on a breast, wooden breast is also present (3). This is due to the similarities in the histological breakdown of the chicken breasts (4). It has been hypothesized that in cases of wooden breasts there is a vast increase in the pH level of the breasts. If this is a trait associated with wooden breast, the increase in pH would lead to a more difficult and lengthy rigor resolution in the processing of the poultry. This increase would lead to delays and hardships in the processing plant. The high pH values would also lead to an increase in the color of the meat, which would lower the quality to consumers (3). As with white striping, the ability to hold water and uptake marinade are both greatly impacted in wooden breast (3). Without this ability to uptake flavor, or hold water, the uses of these poultry products decreases.

(1). Kuttappan, V. A., et al. (2013). "Pathological changes associated with white striping in broiler breast muscles." Poultry Science 92(2): 331-338.

(2). Petracci, M., et al. (2013). "Occurrence of white striping under commercial conditions and its impact on breast meat quality in broiler chickens." Poultry Science 92(6): 1670-1675.

(3). Mudalal, S., et al. (2015). "Implications of white striping and wooden breast abnormalities on quality traits of raw and marinated chicken meat." Animal 9(4): 728-734.

(4). Sihvo, H. K., et al. (2014). "Myodegeneration With Fibrosis and Regeneration in the Pectoralis Major Muscle of Broilers." Veterinary Pathology 51(3): 619-623