Variations in chicken breast meat quality: implications of struggle and muscle glycogen content at death

1. Pectoralis major (P. major) muscle pH and meat quality traits were studied in relation to bird response to ante-mortem stress in three chicken lines: a fast-growing standard line (FGL), a slow-growing French ‘Label Rouge’ line (SGL) and a heavy line (HL). Ninety-nine birds of the three genetic types were slaughtered at their usual marketing age (6, 12 and 6 weeks for FGL, SGL and HL birds, respectively) on the same day. The birds of each line were divided into three different ante-mortem treatment groups: minimum stress (shackling for 10 s) (C), shackling for 2 min (SH) and acute heat plus shackling stress (exposure to 35°C for 3·5 h and shackling for 2 min before stunning) (H + SH). 2. Regardless of chicken line, wing flapping duration (WFD) between hanging and stunning was strongly negatively related to P. major muscle pH at 15 min post-mortem. It was also moderately negatively related to P. major muscle glycolytic potential (GP), which represents glycogen level at death. Increasing WFD induced an increased ultimate pH (pHu) only in HL. The consequences of increased WFD for breast meat traits were dependent on the chicken line: it induced lower L* and b* and higher a* and drip loss in SGL while it only increased breast a* in HL birds. By contrast, WFD variations did not alter breast meat quality traits of FGL birds. Regardless of the chicken line, increased GP was associated with lower pHu and higher L* and drip loss. In SGL, it also increased b* and decreased curing–cooking yield of breast meat. 3. Struggling activity on the shackle line and muscle glycogen content at death could partly explain line and pre-slaughter variations in breast meat pH and quality traits. The water holding capacity of the raw and cooked meat was impaired by long shackling in the case of SGL birds while it was barely affected by ante-mortem conditions in the two standard lines. In conditions which minimised bird struggling (C), SGL and FGL birds had meat with a better water holding ability than that of broilers from the heavy line. However, when broilers were subjected to SH or H + SH conditions, the breast meat water holding capacity of SGL birds was lowered to the same level as that of the heavy line birds.

[1]  T. Grey,et al.  The influence of death struggle on the rate of glycolysis in chicken breast muscle. , 1974, Journal of the science of food and agriculture.

[2]  F. B. Mather,et al.  The Effect of Preslaughter Temperature, Stress, Struggle and Anesthetization on Color and Textural Characteristics of Turkey Muscle , 1978 .

[3]  G. Froning,et al.  Effect of Free Struggle and Preslaughter Excitement on Color of Turkey Breast Muscles , 1982 .

[4]  P. Kettlewell,et al.  Stress of transportation for broilers , 1984, Veterinary Record.

[5]  G. Monin,et al.  Pork of low technological quality with a normal rate of muscle pH fall in the immediate post-mortem period: The case of the Hampshire breed. , 1985, Meat science.

[6]  N. Gregory,et al.  Duration of wing flapping in chickens shackled before slaughter , 1987, Veterinary Record.

[7]  P. Warriss,et al.  Depletion of glycogen reserves in fasting broiler chickens. , 1988, British poultry science.

[8]  J. Girard,et al.  Caractéristiques des carcasses et de la viande du poulet label fermier , 1990 .

[9]  P. Kettlewell,et al.  Indicators of Physiological Stress in Broiler Chickens During Road Transportation , 1992, Animal Welfare.

[10]  Y. Xiong,et al.  Variations in muscle chemical composition, pH, and protein extractability among eight different broiler crosses. , 1993, Poultry science.

[11]  A. Sams,et al.  The Effect of Feed Withdrawal Duration on the Responsiveness of Broiler Pectoralis to Rigor Mortis Acceleration , 1993 .

[12]  Yi Wang,et al.  Characterization of Broiler Meat Quality Factors as Influence by Feed Withdrawal Time , 1994 .

[13]  D. L. Fletcher,et al.  Effect of electrical stunning amperage and peri-mortem struggle on broiler breast rigor development and meat quality. , 1995, Poultry science.

[14]  C. J. Wabeck,et al.  Effects of crating and transport on stress and meat quality characteristics in broilers. , 1997, Poultry science.

[15]  D. L. Fletcher,et al.  Antemortem Holding Temperatures and Broiler Breast Meat Quality , 1997 .

[16]  E. Le Bihan-Duval,et al.  Broiler meat quality: effect of selection for increased carcass quality and estimates of genetic parameters. , 1999, Poultry science.

[17]  J. Mcmurtry,et al.  Relative insensitivity of avian skeletal muscle glycogen to nutritive status. , 1999, Domestic animal endocrinology.

[18]  H. Szałkowska,et al.  The effect of age, genotype and sex on meat quality of broiler chickens , 1999 .

[19]  N. Gault,et al.  Effect of some electrical stimulation variables on wing flapping, post-mortem glycolysis and eating quality characteristics of broiler Pectoralis major muscle , 2000, British poultry science.

[20]  J. Northcutt,et al.  The effect of holding temperature on live shrink, processing yield, and breast meat quality of broiler chickens. , 2001, Poultry science.

[21]  C. Berri,et al.  Effect of selection for improved body composition on muscle and meat characteristics of broilers from experimental and commercial lines. , 2001, Poultry science.

[22]  M. Mitchell,et al.  Acute heat stress-induced alterations in blood acid-base status and skeletal muscle membrane integrity in broiler chickens at two ages: implications for meat quality. , 2001, Poultry science.

[23]  D. P. Smith,et al.  The effect of age, dietary carbohydrate source, and feed withdrawal on broiler breast fillet color. , 2002, Poultry science.

[24]  C. Berri,et al.  Variation of chicken technological meat quality in relation to genotype and preslaughter stress conditions. , 2003, Poultry science.

[25]  M. Picard,et al.  Further processing characteristics of breast and leg meat from fast-, medium- and slow-growing commercial chickens , 2005 .

[26]  C. Berri,et al.  Behavioural and physiological responses of three chicken breeds to pre-slaughter shackling and acute heat stress , 2005, British poultry science.

[27]  R. H. Dalrymple,et al.  A method for the extraction of glycogen and metabolites from a single muscle sample , 2007 .

[28]  R. Jeacocke Continuous measurements of the pH of beef muscle in intact beef carcases , 2007 .