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Elasticity of Muscle of Epinephrine Treated Chicken
POLYPHOSPHATES I N C H I L L I N G W A T E R
mendation of the product by the U. S. Department of Agriculture to the exclusion of others t h a t m a y be suitable. REFERENCES
May, K. N., R. L. Helmer and R. L. Saffle, 1962. Effect of phosphate treatment on carcass weight changes and organoleptic quality of cut-up chicken. Poultry Sci. 41: 1665. Mountney, G. J., and F. C. Arganosa, 1962. The effects of phosphates on moisture absorption, retention and cooking losses of broiler carcasses. Poultry Sci. 41: 1668. Schermerhorn, E. P., and W. J. Stadelman, 1962. Effects of polyphosphates on water uptake, moisture retention, and cooking loss in broilers. Poultry Sci. 41: 1680. Spencer, J. V., and L. E. Smith, 1962. The effect of chilling chicken fryers in a solution of polyphosphates upon moisture uptake, microbial spoilage, tenderness, juiciness and flavor. Poultry Sci. 41: 1685.
Elasticity of Muscle of Epinephrine Treated Chicken M. F . P O O L
Western Regional Research Laboratory,1 Albany, California (Received for publication November 22, 1962)
P
R E - M O R T E M injection of epinephrine into chickens results in muscle t h a t is tender when cooked immediately after slaughter, with out the aging period of six to twelve hours required for normal muscle (de Fremery and Pool, 1960a, 1962). The epinephrine treatment also brings about an essential exhaustion of the normal supply of muscle glycogen. Normally, glycogen is degraded to lactic acid by a series of cyclic anaerobic reactions which, in their intermediate steps, maintain a high level of adenosine triphosphate (ATP) for several hours post mortem. Consequently the post-mortem A T P level drops rapidly in the epinephrine-treated muscle b u t only a small decrease in p H occurs. This paper reports the time course of 1 A laboratory of the Western Utilization Research and Development Division, Agricultural Research Service, U. S. Department of Agriculture.
the changes in extensibility and length of muscles from epinephrine-treated chickens. Equipment for measuring extensibility and length of strips of pectoralis major muscle under periodic loading was derived from t h a t of Bate-Smith (1939) and BateSmith and Bendall (1949). Linear variable differential transformers served as transducers, and electrical means of recording were used. Dual equipment and a twochannel recorder permitted simultaneous measurements on epinephrine-treated and control muscle strips. Muscle strips were stressed by applying a load, never beyond the elastic limit, for 3 minutes or 7.5 minutes of a 15-minute cycle. The point of maximum modulus and minimum length occurs somewhat earlier with the longer loading period but, since the differences between the experimental and control muscles were not affected, the d a t a have
Downloaded from http://ps.oxfordjournals.org/ at New York University on May 4, 2015
Klose, A. A., A. A. Campbell and H. L. Hanson, 1962. Influence of polyphosphates in chilling water on quality of poultry meat. Poultry Sci. 41: 1655. Mahon, J. A., 1962. You can reduce poultry "weep." Poultry Processing and Marketing, 68(8): 16-17, 24, 26. Marion, W. W., and R. H. Forsythe, 1962. Protection afforded lipids of turkey meat by butylated hydroxyanisole, egg white solids, gelatin and tripolyphosphate (Kena). Poultry Sci. 41: 1663.
749
750
M. F. POOL
r2o
10
[ 2 0
10
20
60
Control
70
80
90
Epinephrine -•-Shortening
10
20
30
40
SO
60
70
80
1 FIG. 1. Typical strip chart recording of 2 muscle strips; 15-minute cycle, 3 minutes loading, 12 minutes unloaded.
90
Downloaded from http://ps.oxfordjournals.org/ at New York University on May 4, 2015
10
ELASTICITY OF CHICKEN MUSCLE
rapidly to about 70% of initial length, then increased slowly over the remainder of the 24 hour period to about 80% of initial length (Fig. 3). The controls shortened slightly, to about 90% of initial value, then recovered almost their original length. Epinephrine-treated muscles show changes in extensibility and length which are similar to muscles stimulated by various physical agents (de Fremery and Pool, 1960b). However, epinephrine-treated muscles are generally tender immediately post mortem, in contrast to stimulated muscles which are usually permanently tough. Hence, these observations on the changes in the elastic properties of epinephrine-treated muscle provide further evidence that the extensibility changes undergone by muscle during the course of rigor mortis and the development of tenderness in muscle are separate phenomena. The first is closely related to the level of ATP present and may involve some irreversible protein-protein interaction (de Fremery and Pool, 1960b). The second, or tenderization-toughening phenomenon, appears to be quite sensitive to the rate of anaerobic degradation of glycogen to lactic acid (de Fremery and Pool,
100
Epinephrine
Hours Post Mortem FIG. 2. Changes in modulus of elasticity with time post mortem.
Downloaded from http://ps.oxfordjournals.org/ at New York University on May 4, 2015
been pooled for the results given here. Figure 1 is typical of the strip-chart records from which the data were taken. Five chickens (4 to 5 lb. fryers) were injected subcutaneously 18 hours prior to slaughter with 3 mg. of epinephrine per kg. of body weight. The treated birds were held without feed after injection while the 5 control birds were on full feed throughout. For the control birds, the typical delay in increase in elastic modulus (force times length divided by product of elongation and cross sectional area) was followed by a rapid increase to a maximum (Fig. 2). By contrast, the curve for epinephrinetreated birds shows no delay, indeed some loss of extensibility was apparent during the ten-minute period required for preparation and insertion of the muscle strip in the apparatus. Maximum loss of extensibility occurred sooner in the epinephrinetreated muscles (7-8 hrs.) than in the control group (10-12 hrs.). After reaching their maxima, both groups regained some of their elasticity during the remainder of the 24 hour period; the control birds showed the greater effect. Length (under very light load) of epinephrine-treated muscle strips decreased
751
752
M. F. POOL
100
90
1
Control
£80
\
c V
_l
o70 •
—
- V^_____ Epinephrine Fig. 3
5? 6 0 1 10 Hours Post Mortem
I 15
i 20
25
FIG. 3. Changes in rest length with time post mortem.
1960a). The mechanism of this second effect and the basic change in the muscle fiber on tenderization or toughening represent the objective of Continuing studies. REFERENCES Bate-Smith, E. C , 1939. Changes in elasticity of mammalian muscle undergoing rigor mortis. J. Physiol. 96: 176-193. Bate-Smith, E. C , and J. R. Bendall, 1949. Factors determining the time course of rigor mortis. J. Physiol. 110: 47-65.
de Fremery, D., and M. F. Pool, 1960a. The tenderization pattern in adrenaline treated poultry. Technical program and abstracts of 20th Annual Meeting, Institute of Food Technologists. Abs. 165, p. 42. de Fremery, D., and M. F. Pool, 1960b. Biochemistry of chicken muscle as related to rigor mortis and tenderization. Food Res. 25: 73-87. de Fremery, D., M. F. Pool, and H. Lineweaver, 1962. Poultry tenderness and post-mortem glycolysis. Proc. 12th World's Poultry Congress, 418-421.
Calcium and Phosphorus Requirements of Finishing Broilers Using Phosphorus Sources of Low and High Availability1 P. W. WALDROUP, C. B. AMMERMAN AND R. H. HARMS Florida Agricultural Experiment Stations, Gainesville, Florida (Received for publication November 27, 1962)
T
HE National Research Council (1960) has suggested that the dietary calcium and phosphorus levels for broilers 0-8 weeks of age be 1.0 and 0.6 percent, 1 Florida Agricultural Journal Series No. 1615.
Experiment
Stations,
respectively. However, requirements as reported by various workers have been quite variable. Calcium requirements have ranged from 0.60 percent (Simco and Stephenson, 1960; Formica el al., 1961) to levels as high as 2.14 percent (Sherwood, 1932). Phosphorus requirements have
Downloaded from http://ps.oxfordjournals.org/ at New York University on May 4, 2015
1
50
mendation of the product by the U. S. Department of Agriculture to the exclusion of others t h a t m a y be suitable. REFERENCES
May, K. N., R. L. Helmer and R. L. Saffle, 1962. Effect of phosphate treatment on carcass weight changes and organoleptic quality of cut-up chicken. Poultry Sci. 41: 1665. Mountney, G. J., and F. C. Arganosa, 1962. The effects of phosphates on moisture absorption, retention and cooking losses of broiler carcasses. Poultry Sci. 41: 1668. Schermerhorn, E. P., and W. J. Stadelman, 1962. Effects of polyphosphates on water uptake, moisture retention, and cooking loss in broilers. Poultry Sci. 41: 1680. Spencer, J. V., and L. E. Smith, 1962. The effect of chilling chicken fryers in a solution of polyphosphates upon moisture uptake, microbial spoilage, tenderness, juiciness and flavor. Poultry Sci. 41: 1685.
Elasticity of Muscle of Epinephrine Treated Chicken M. F . P O O L
Western Regional Research Laboratory,1 Albany, California (Received for publication November 22, 1962)
P
R E - M O R T E M injection of epinephrine into chickens results in muscle t h a t is tender when cooked immediately after slaughter, with out the aging period of six to twelve hours required for normal muscle (de Fremery and Pool, 1960a, 1962). The epinephrine treatment also brings about an essential exhaustion of the normal supply of muscle glycogen. Normally, glycogen is degraded to lactic acid by a series of cyclic anaerobic reactions which, in their intermediate steps, maintain a high level of adenosine triphosphate (ATP) for several hours post mortem. Consequently the post-mortem A T P level drops rapidly in the epinephrine-treated muscle b u t only a small decrease in p H occurs. This paper reports the time course of 1 A laboratory of the Western Utilization Research and Development Division, Agricultural Research Service, U. S. Department of Agriculture.
the changes in extensibility and length of muscles from epinephrine-treated chickens. Equipment for measuring extensibility and length of strips of pectoralis major muscle under periodic loading was derived from t h a t of Bate-Smith (1939) and BateSmith and Bendall (1949). Linear variable differential transformers served as transducers, and electrical means of recording were used. Dual equipment and a twochannel recorder permitted simultaneous measurements on epinephrine-treated and control muscle strips. Muscle strips were stressed by applying a load, never beyond the elastic limit, for 3 minutes or 7.5 minutes of a 15-minute cycle. The point of maximum modulus and minimum length occurs somewhat earlier with the longer loading period but, since the differences between the experimental and control muscles were not affected, the d a t a have
Downloaded from http://ps.oxfordjournals.org/ at New York University on May 4, 2015
Klose, A. A., A. A. Campbell and H. L. Hanson, 1962. Influence of polyphosphates in chilling water on quality of poultry meat. Poultry Sci. 41: 1655. Mahon, J. A., 1962. You can reduce poultry "weep." Poultry Processing and Marketing, 68(8): 16-17, 24, 26. Marion, W. W., and R. H. Forsythe, 1962. Protection afforded lipids of turkey meat by butylated hydroxyanisole, egg white solids, gelatin and tripolyphosphate (Kena). Poultry Sci. 41: 1663.
749
750
M. F. POOL
r2o
10
[ 2 0
10
20
60
Control
70
80
90
Epinephrine -•-Shortening
10
20
30
40
SO
60
70
80
1 FIG. 1. Typical strip chart recording of 2 muscle strips; 15-minute cycle, 3 minutes loading, 12 minutes unloaded.
90
Downloaded from http://ps.oxfordjournals.org/ at New York University on May 4, 2015
10
ELASTICITY OF CHICKEN MUSCLE
rapidly to about 70% of initial length, then increased slowly over the remainder of the 24 hour period to about 80% of initial length (Fig. 3). The controls shortened slightly, to about 90% of initial value, then recovered almost their original length. Epinephrine-treated muscles show changes in extensibility and length which are similar to muscles stimulated by various physical agents (de Fremery and Pool, 1960b). However, epinephrine-treated muscles are generally tender immediately post mortem, in contrast to stimulated muscles which are usually permanently tough. Hence, these observations on the changes in the elastic properties of epinephrine-treated muscle provide further evidence that the extensibility changes undergone by muscle during the course of rigor mortis and the development of tenderness in muscle are separate phenomena. The first is closely related to the level of ATP present and may involve some irreversible protein-protein interaction (de Fremery and Pool, 1960b). The second, or tenderization-toughening phenomenon, appears to be quite sensitive to the rate of anaerobic degradation of glycogen to lactic acid (de Fremery and Pool,
100
Epinephrine
Hours Post Mortem FIG. 2. Changes in modulus of elasticity with time post mortem.
Downloaded from http://ps.oxfordjournals.org/ at New York University on May 4, 2015
been pooled for the results given here. Figure 1 is typical of the strip-chart records from which the data were taken. Five chickens (4 to 5 lb. fryers) were injected subcutaneously 18 hours prior to slaughter with 3 mg. of epinephrine per kg. of body weight. The treated birds were held without feed after injection while the 5 control birds were on full feed throughout. For the control birds, the typical delay in increase in elastic modulus (force times length divided by product of elongation and cross sectional area) was followed by a rapid increase to a maximum (Fig. 2). By contrast, the curve for epinephrinetreated birds shows no delay, indeed some loss of extensibility was apparent during the ten-minute period required for preparation and insertion of the muscle strip in the apparatus. Maximum loss of extensibility occurred sooner in the epinephrinetreated muscles (7-8 hrs.) than in the control group (10-12 hrs.). After reaching their maxima, both groups regained some of their elasticity during the remainder of the 24 hour period; the control birds showed the greater effect. Length (under very light load) of epinephrine-treated muscle strips decreased
751
752
M. F. POOL
100
90
1
Control
£80
\
c V
_l
o70 •
—
- V^_____ Epinephrine Fig. 3
5? 6 0 1 10 Hours Post Mortem
I 15
i 20
25
FIG. 3. Changes in rest length with time post mortem.
1960a). The mechanism of this second effect and the basic change in the muscle fiber on tenderization or toughening represent the objective of Continuing studies. REFERENCES Bate-Smith, E. C , 1939. Changes in elasticity of mammalian muscle undergoing rigor mortis. J. Physiol. 96: 176-193. Bate-Smith, E. C , and J. R. Bendall, 1949. Factors determining the time course of rigor mortis. J. Physiol. 110: 47-65.
de Fremery, D., and M. F. Pool, 1960a. The tenderization pattern in adrenaline treated poultry. Technical program and abstracts of 20th Annual Meeting, Institute of Food Technologists. Abs. 165, p. 42. de Fremery, D., and M. F. Pool, 1960b. Biochemistry of chicken muscle as related to rigor mortis and tenderization. Food Res. 25: 73-87. de Fremery, D., M. F. Pool, and H. Lineweaver, 1962. Poultry tenderness and post-mortem glycolysis. Proc. 12th World's Poultry Congress, 418-421.
Calcium and Phosphorus Requirements of Finishing Broilers Using Phosphorus Sources of Low and High Availability1 P. W. WALDROUP, C. B. AMMERMAN AND R. H. HARMS Florida Agricultural Experiment Stations, Gainesville, Florida (Received for publication November 27, 1962)
T
HE National Research Council (1960) has suggested that the dietary calcium and phosphorus levels for broilers 0-8 weeks of age be 1.0 and 0.6 percent, 1 Florida Agricultural Journal Series No. 1615.
Experiment
Stations,
respectively. However, requirements as reported by various workers have been quite variable. Calcium requirements have ranged from 0.60 percent (Simco and Stephenson, 1960; Formica el al., 1961) to levels as high as 2.14 percent (Sherwood, 1932). Phosphorus requirements have
Downloaded from http://ps.oxfordjournals.org/ at New York University on May 4, 2015
1
50