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The Cooking of Fowl with Various Salts for Precooked Poultry Products1
668
B. L. GOODMAN AND R. G. JAAP
in chickens and turkeys. Poultry Sci. 36: 1134. Lerner, I. M., 1950. Population Genetics and Animal Improvement. University Press, Cambridge. Newcomer, E. H., 1957. The mitotic chromosomes of the domestic fowl. J. Heredity, 48: 2^,7-234. Nordskog, A. W., and A. J. Wyatt, 1953. Heritability estimates. Mimeograph sheet. Oliver, M. M., B. E. Bohren and V. L. Anderson, 1957. Heritability and selection efficiency of several measures of egg production. Poultry Sci. 36: 395-402.
Thomas, C. H., W. L. Blow, C. C. Cockerham and E. W. Glazener, 1958. Heritability of body weight, gain, feed consumption, and feed conversion in broilers. Poultry Sci. 37: 862-869. Yamada, Y., 1958. Heritability and genetic correlations in economic characters in chickens. Japanese J. Genetics, 33 : 13-22. Yamada, Y., B. B. Bohren and L. B. Crittenden, 1958. Genetic analysis of a White Leghorn closed-flock apparently plateaued for egg production. Poultry Sci. 37 : 565-580.
O. J. KAHLENBERG AND E. M. FUNK Poultry Husbandry Department, University of Missouri, Columbia, Missouri (Received for publication July 18, I960)1 /
~¥~VHE continued utilization of poultry •*• products in frozen and canned foods is dependent upon the development and improvement of commercial processing methods. It is generally known that the keeping qualities of precooked frozen meats depends on the way meats are cooked, method of packaging, type of seasoning and storage temperatures. Much of the research reported in the literature on quality of chicken meat as affected by cooking methods has been with young chickens. There are a number of papers which describe palatability of mature birds cooked with water but basic data are not available for recommending commercial cooking methods. Hanson et al. (1950) reported that the older less tender chickens of food quality could be successfully utilized in precooked frozen foods for a more flavorful product than that obtained from younger birds. Simmering or pressure-cooking was recommended to make the meat the desired degree of tenderness. Vail and Conrad (1948) described a procedure of disjointing 'Contribution from the Missouri Agricultural Experiment Station. Journal Series No. 2182 approved by Director.
hens and cooking the parts by simmering for three hours. Swickard, Harkin and Paul (1954) determined the relationship of steaming, simmering and pressure-cooking as applied to home preparations. They found that the meat of steamed and simmered hens was generally rated higher than pressure-cooking by panel evaluations, shear force and press-liquid tests. Steamed and simmered light meat was significantly more tender than pressure-cooked light meat. Woodroof and Shelor (1955) reported that chicken when cooked with moist heat may be satisfactorily frozen and stored for one year or more, while turkey may be held for from 3 to 6 months. Working with turkeys, Hanson et al. (1950) observed that the roasting method had no advantage over simmering or pressure-cooking in producing a product with a typical "roast turkey flavor" and had the disadvantage of accelerating the development of fat rancidity. In studies of red meat, Deatherage (1955) reported that the water-holding capacity of meat proteins was found to be directly related to shrinkage on cooking, drip on freezing and thawing, and tenderness. Wierbicki, Cahill and
Downloaded from http://ps.oxfordjournals.org/ at New York University on May 23, 2015
The Cooking of Fowl with Various Salts for Precooked Poultry Products 1
COOKING OF FOWL
sodium hexametaphosphate, 2.0 and 4.0% sodium tripolyphosphate and 2.0% sodium orthophosphate. The methods of cooking were boiling, simmering and pressure-cooking. Boiling represents a rolling boil for 90 min., simmering consists of cooking at 1 hr. 45 min. at 200°F. followed by an additional 45 min. at 210°F. and pressurecooking consists of cooking in an aluminum pressure-cooker at 15 p.s.i.g. for 20 min., allowing for an additional 25 min. for cooling before the lid of the pressurecooker could be removed. Since these procedures were for developing methods of processing fowl for commercial precooked frozen and canned products the birds were not sized according to weight and cooked for different time periods. Birds held at varying storage periods were grouped together for these studies. The degree of tenderness of the breast meat was measured with the Kramer shear press described by MATERIALS AND METHODS Kramer, Burkhardt and Rogers (1951) Old fowl of White Leghorn strains, 16 using the hydraulic ram adjusted to 225 to 20 months of age, obtained from the lbs. for the 3000 lb. proving ring. Samples University Poultry Farm were sacrificed, of breast meat were trimmed from either scalded, warm eviscerated, chilled in ice end of the longitudinal axis of each side water, drained, and packaged in Cryovac of the breast to fit the shearing cell, and bags. The packaged birds were frozen at then placed in the cell so that the meat — 20°F. in a blast tunnel and then stored at fibers were at an axis opposite to the cross 0°F. for 1 to 17 months before used. Birds grooves of the cell. Measurements were were removed from the freezer and thawed made of the force required to shear across in a 38°F. cooler the day before they were the grain of the meat. Separate readings to be cooked. Individual weights were were taken from both the left and right taken of the thawed eviscerated carcasses, sides of the cooked breast meat of each without giblets and necks, both before and bird, the average of the two being taken as the tenderness value of each cooked after cooking. Comparisons were made of various cook- bird. The trimmed portion was weighed ing procedures on old fowl with and with- in grams. The shear force values were calout the incorporation of salts in the water, culated as pounds per gram of sample of for cooking losses and degree of tenderness meat. A low shear value indicates tender in the breast meat. The salts initially meat. Shannon, Marion and Stadelman studied were 2.0 and 4.0% sodium chloride, (1957) reported a coefficient correlation of 0.75 and 1.50% potassium chloride, 0.60 0.86 between Kramer shear press values and 1.20% calcium chloride, 0.50 and and organoleptic panel scores of poultry 1.00% magnesium chloride, 2.0 and 4.0% meat.
Downloaded from http://ps.oxfordjournals.org/ at New York University on May 23, 2015
Deatherage (1957) found that the chlorides of sodium, potassium, calcium and magnesium when added to ground beef prior to heating increased the water-holding capacity of meat proteins when heated to 70°C. (158°F.). The juice expressed on heating was less for the calcium and magnesium chlorides than for the sodium and potassium chlorides. Magnesium chloride showed the most pronounced effect. Tims and Watts (1958) reported on the value of phosphates for red meats in decreasing cooking losses. It seemed appropriate to extend some of these findings to poultry meat. The objective of this investigation was to compare the effect of various cooking procedures on old fowl, with and without the incorporation of salts in the water, for cooking losses, degree of tenderness in the breast meat, and amount of fat in the thigh meat.
669
670
O. J. KAHLENBERG AND E. M.
RESULTS AND DISCUSSION The percentages and kinds of salts used were found to be limited because of the effect on taste of the poultry meat. When birds were cooked in either sodium hexametaphosphate or sodium orthophosphate, the pH values of the broth were on the acid side (pH 5.3 to 6.3). When either 2% sodium orthophosphate or 4% sodium hexametaphosphate were added to the cooking water the flavor of the cooked meat was rated from "slightly acid" to
"acid." In general the pH values of the broth after cooking in tap water or with the other salt solutions were on the alkaline side (range pH 7.3 to 9.1). Flavor comments for the meat cooked in tap water or the various salt solutions (except sodium chloride) were rated as "very flat." Those cooked in 4% sodium chloride solution were considered as "slightly salty" but the birds cooked in 2% sodium chloride solution were satisfactory in flavor. In view of these results the number of salt solutions were limited to those containing potassium chloride, sodium chloride and sodium tripolyphosphate. Cooking Losses. The average percent total cooking losses and Kramer shear values of fowl cooked by various methods are shown in Table 1. It was believed that the fatness of the bird was covering up expected differences due to the type and level of salt. Although the fat losses were not obtained on all of the birds, statistical treatment of the available data showed that the coefficient correlations between body weight and percent fat loss, and body weight and percent non-fat loss were for boiling 0.35 and —0.27, for simmering 0.76 and —0.23, for pressure-cooking 0.38 and 0.53 respectively. The coefficient correlations between percent fat and non-fat losses were —0.85, —0.67, and —0.36 for boiling, simmering and pressure-cooking re-
TABLE 1.—Average percent total cooking losses and Kramer shear values of fowl cooked by various methods Bo:iling Treatment
T a p water 0.75% Potassium Chloride 1.50% Potassium Chloride 2.0% Sodium Chloride 4.0% Sodium Chloride 2.0% Sodium Tripolyphosphate 4.0% Sodium Tripolyphosphate
Avg. No. carcass birds wt.
7 6 6 6 7 6 6
g1,446 1,525 1,382 1,335 1,589 1,656 1,502
Lbs. Cook- force ing p e r g . loss meat
%
34.5 37.7 40.9 40.5 40.1 39.5 40.1
* Aluminum of pressure cooker corroded due to salt.
20.20 18.36 21.29 18.12 18.13 20.73 18.15
Simmering Avg. No. carcass birds wt.
8 6 6 6 6 6 6
g1,489 1,270 1,313 1,474 1,829 1,760 1,547
Lbs. Cook- force ing p e r g . loss meat
% 37.5 36.1 40.7 39.1 39.0 37.4 37.3
18.33 19.20 21.62 19.36 15.22 17.49 18.00
Avg. No. carcass birds wt.
8 12 6 6 6 2* 2*
g. 1,486 1,435 1,283 1,568 1,450 1,153 1,509
Pressure cooking Lbs. Cook- force ing per g. loss meat
%
37.1 38.4 40.5 41.6 40.3 36.5 47.9
15.15 15.22 17.01 18.11 14.35 17.55 11.03
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Determinations of pH were made on the salt solutions and on the broth after cooking. When broth fat was measured, it was removed by means of a separatory funnel and weighed. The thigh meat without skin was removed from the bones, placed in glass jars, sealed and frozen. The frozen meat was prepared in a 0°F. room by grinding it three times in a hand-operated meat chopper. The ground samples were put back into the same glass jars and kept in the freezer locker for later analyses of fat and moisture. Moisture and fat determinations were made on duplicate samples of thigh meat by the A.O.A.C. method (19SS). Analysis of variance was calculated according to Snedecor (1956) and significance between means by Duncan's new multiple range test (19SS).
FUNK
671
COOKING OF FOWL TABLE 2.—Average percent of non-fat cooking losses adjusted for variations of fat of bird Boiling
No. birds
Avg. carcass wt.
27.7
4
g1,564
28.6
1,203 1,408
30.2 25.7
4 4
1,492 1,310
27.9 26.7
4 4
1,452 2,021
28.1 23.5
4 4
1,630 1,352
26.7 27.1
6 6
1,760 1,547
25.0 26.4
No. birds
29.0
6
1,492
1,501 1,450
28.7 27.9
4 4
4 5
1,336 1,552
26.1 30.4
6 6
1,656 1,502
27.4 29.8
No. birds
T a p water
3
g1,439
0 . 7 5 % Potassium chloride 1.50% Potassium chloride
4 4
2 . 0 % Sodium chloride 4 . 0 % Sodium chloride 2 . 0 % Sodium Tripolyphosphate 4 . 0 % Sodium Tripolyphosphate
Treatment
Adj. non-fat cooking losses
%
Adj. non-fat cooking losses
%
Adj. non-fat cooking losses
%
either the "salt" or "level within the salt" were not significant. The differences due to "treatment" were significant at the 5 percent level. Students' Duncan Multiple Range test shows that simmering had significantly lower non-fat cooking losses than boiling. The non-fat cooking losses were 26.7 percent for simmering, 27.4 percent for pressure-cooking and 28.5 percent for boiling. The differences between pressurecooking and either boiling or simmering were not significant. It should be borne in mind that the cooking losses attributed to the three cooking methods could also be partially due to the length of cooking time. It is not known for example if simmering for 2j4 TABLE 3.—Analysis of variance for non-fat cooking losses adjusted for variations of fat of bird Source of variance Salt Level w/n salt Method w/n level w/n salt (Treatment) Error
d.f.
m.s.
3 3 12
5.97 16.81 15.92
67
7.72
f-value 0.36 1.06 2.06*
Total 85 * Significant at the 0.05 level. Studentized Ranges for a 5% Multiple Range Test Pressure SimTreatment Boil Cook mer Non-fat cooking loss means 28.5 27.4 26.7
Means not underscored by the same broken line are significantly different. Means which are underscored are not significantly different.
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spectively. These relationships expressed as regression coefficients were found to be — 0.67 for boiling, — 0.S6 for simmering and —0.26 for pressure-cooking. An analysis of covariance showed that the regression coefficients were significantly different from a common regression coefficient (p = .10) level. The differences between the methods of cooking after adjustment for differences in the fat of the bird were found to be significant at the 0.03 probability level. Since the relationship between percentages of fat and non-fat losses were significantly different between the cooking methods, a single regression coefficient could not be used for the entire group. Using the statistical regression coefficient for each cooking method, the percentage of non-fat losses were adjusted to account for the differences in the fatness of birds. Table 2 shows the average percent of non-fat cooking losses adjusted for variations of fat of the bird when cooked by various methods. The differences in fatness were so great in these experimental birds that they would have covered up expected differences due to the type and level of salt. The analysis of variance of the non-fat cooking losses adjusted for variations in fat content among the birds cooked by each method is shown in Table 3. It will be noted in Table 3 that the differences in non-fat cooking losses among
Pressure cooking
Simmering Avg. carcass wt.
Avg. carcass wt.
672
0. J. KAHLENBERG AND E. M. TABLE 4.—Analysis of variance for Kramer shear force values
Source of variance Salt Level w / n salt Method w / n level w/n salt (Treatment) Error
d.f.
f-value
3 3 12
11.1506 51.8129 45.9533
107
12.4669
0.22 1.13 3.69*
Total 125 ** Significant at the .01 level. Studentized Ranges for a 1% Level New Multiple Range Test Pressure Treatment Boil Simmer Cook Shear Force Means 19.28 18.45 15.81
hrs. and boiling for 1}4 hrs. are equivalent from a time-temperature relationship. Kramer Shear Force Values. Analyses of variance for Kramer shear force values (Table 4) show that these values due to the salts themselves and to the "level within salt" were not significant but that "treatment" was very significant. Students' Duncan Multiple Range test showed that pressure-cooking gave significantly lower shear force values of the cooked breast meat, than did either boiling or simmering (Table 4). Although the experimental conditions were different from these studies, Swickard, Harkin and Paul (1954) reported that the simmered and steamed light meat as measured by the Warner-Bratzler shear values and palatability scores, was significantly more tender than the pressurecooked light meat, and that simmered dark meat was significantly more tender than pressure-cooked dark meat. It will also TABLE
5 . --Average
be observed in Table 4 that differences of shear force mean values of the breast meat at a result of either boiling or simmering were insignificant. Fat Content in Cooked Thigh Meat. The results recorded in Table 5 show that the percentage of fat, on a dry basis, was consistently lower when carcasses were pressure-cooked than when birds were either simmered or boiled. An analysis of variance for fat in cooked fowl thigh meat (Table 6) shows that neither the salts themselves nor the "level within salt" were significant, but that "treatment" was highly significant. Further statistical treatment of the means revealed that the thigh meat of pressurecooked carcasses was significantly lower in fat than the thigh meat of birds which were either boiled or simmered. There was no significant difference in the fat content of thigh meat when birds were cooked by either simmering or boiling. SUMMARY
Comparison of cooking losses, degree of tenderness in the breast meat, and the amount of fat in the thigh meat have been made on old fowl cooked by boiling, simmering and pressure-cooking with and without salts in the cooking water. The cooking of old fowl in the salt solutions outlined in these studies had no advantage over cooking in water with respect to adjusted non-fat cooking losses, tenderness of cooked breast meat as judged
percent fat and moisture in thigh meat of fowl cooked by various methods Boiling
Treatment
No. birds
Fat
7 6 6 6 7 6 6
/o 10.96 11.87 11.58 9.98 10.52 10.44 10.24
07
Tap water 0.75% Potassium chloride j . 5 0 % Potassium chloride 2-0% Sodium chloride 4.0% Sodium chloride 2-0% Sodium tripolyphosphate 4.0% Sodium tripolyphosphate
Moisture
%
60.85 59.71 59.39 60.49 59.61 60.55 60.08
Simmering Fat dry basis
%
27.24 29.21 28.37 25.18 25.91 26.19 25.53
No. birds
Fat
% 9.48 7.92 12.30 10.73 12.44 12.32 12.17
Moisture
%
61.32 62.25 58.86 60.50 58.88 60.01 59.61
Pressure cooking Fat dry basis
No. birds
Fat
12 6 6 6
6.78 6.17 9.12 10.55 9.76
%
24.45 20.98 29.56 26.86 30.05 30.60 29.74
%
Moisture
%
62.77 62.29 60.19 60.03 60.00
Fat dry basis
%
17.88 16.30 22.69 26.09 24.22
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Means not underscored by the same line are significantly different at the .01 level. Means which are underscored by the same line are not significantly different.
FUNK
COOKING OF FOWL TABLE 6.—Analysis of variance for fat in cooked fowl thigh meat Source of variance Salt Level Method w / n level w / n salt (Treatment) Error
d.f.
m.s.
f-value
3 3 12
162.1518 133.2552 117.5207
1.217 1.134 3.29**
107
35.7219
Total 125 ** Significant at the .01 level. Studentized Ranges of a 1% Level New Multiple Range Test Pressure Treatment Simmer Boil Cook F a t Means 27.33 26.79 20.44
by the Kramer shear test and the amount of fat in the cooked thigh meat. Significantly lower adjusted non-fat cooking losses were obtained by simmering than by boiling. Differences in adjusted non-fat cooking losses between pressure cooking and either boiling or simmering were found to be insignificant. Pressure cooking gave significantly lower Kramer shear force values of the cooked breast meat than did either boiling or simmering. Differences in shear values as a result of either boiling or simmering were not significant. The thigh meat of pressure-cooked carcasses was found to be significantly lower in fat than the thigh meat of birds which were either boiled or simmered. No significant differences in the fat content of cooked thigh meat were obtained when carcasses were cooked by either simmering or boiling. ACKNOWLEDGMENT
The authors are indebted to Dr. A. B. Stephenson and Mr. Bobby R. Jones of the Poultry Husbandry Department for their counsel and guidance in the statistical analyses of the data. Moisture and fat de-
terminations were made by the University of Missouri Experiment Station Chemical Laboratories. REFERENCES Association of Official Agricultural Chemists, 1955. Official and Tentative Methods of Analysis. 8th edition. Deatherage, F. E., 1955. Investigations on the nature of certain qualities in meat. Proceedings, Seventh Research Conference. American Meat Institute: 52-61. Duncan, D. B., 1955. Multiple range and multiple F tests. Biometrics, 11: 1-42. Hanson, H. L., H. M. Winegarden, M. B. Horton and H. Lineweaver. 19S0. Preparation and storage of frozen cooked poultry and vegetables. Food Technology, 4 : 430-434. Kramer, A., G. J. Burkhardt and H. P. Rogers, 1951. The shear press: a device for measuring food quality. Canner, 112: 34. Shannon, W. G., W. W. Marion and W. J. Stadelman, 1957. Effect of temperature and time of scalding on the tenderness of breast meat of chicken. Food Technology, 11: 284-286. Snedecor, G. W. 1956. Statistical Methods. Iowa State College Press, Ames, Iowa. Swickard, M. T., A. M. Harkin and B. J. Paul, 1954. Relationship of cooking methods, grades and frozen storage to quality of cooked mature Leghorn hens, 1954. U.S. Dept. Agr. Technical Bulletin No. 1077. Tims, M. J., and B. M. Watts, 1958. Protection of cooked meats with phosphates. Food Technology, 12: 240-243. Vail, G. E., and R. M. Conrad, 1948. Determination of palatability changes occurring in frozen poultry. Food Research, 13: 347-357. Wierbicki, E., V. R. Cahill and F. E. Deatherage, 1957. Effects of added sodium chloride, potassium chloride, calcium chloride, magnesium chloride and citric acid on meat shrinkage at 70° C. and of added sodium chloride on drip losses after freezing and thawing. Food Technology, 1 1 : 74-76. Woodroof, J. C , and E. Shelor, 1955. Keeping quality during storage of precooked frozen foods. Precooked Frozen Foods, A Symposium. Quartermaster Food and Container Institute for Armed Forces. U.S. Army.
JULY 18-20. AMERICAN POULTRY AND HATCHERY FEDERATION CONGRESS AND EXPOSITION, MUNICIPAL AUDITORIUM, MINNEAPOLIS, MINNESOTA.
Downloaded from http://ps.oxfordjournals.org/ at New York University on May 23, 2015
Means not underscored by the same line arc significantly different at the .01 level. Means which are underscored by the same line are not significantly different.
673
B. L. GOODMAN AND R. G. JAAP
in chickens and turkeys. Poultry Sci. 36: 1134. Lerner, I. M., 1950. Population Genetics and Animal Improvement. University Press, Cambridge. Newcomer, E. H., 1957. The mitotic chromosomes of the domestic fowl. J. Heredity, 48: 2^,7-234. Nordskog, A. W., and A. J. Wyatt, 1953. Heritability estimates. Mimeograph sheet. Oliver, M. M., B. E. Bohren and V. L. Anderson, 1957. Heritability and selection efficiency of several measures of egg production. Poultry Sci. 36: 395-402.
Thomas, C. H., W. L. Blow, C. C. Cockerham and E. W. Glazener, 1958. Heritability of body weight, gain, feed consumption, and feed conversion in broilers. Poultry Sci. 37: 862-869. Yamada, Y., 1958. Heritability and genetic correlations in economic characters in chickens. Japanese J. Genetics, 33 : 13-22. Yamada, Y., B. B. Bohren and L. B. Crittenden, 1958. Genetic analysis of a White Leghorn closed-flock apparently plateaued for egg production. Poultry Sci. 37 : 565-580.
O. J. KAHLENBERG AND E. M. FUNK Poultry Husbandry Department, University of Missouri, Columbia, Missouri (Received for publication July 18, I960)1 /
~¥~VHE continued utilization of poultry •*• products in frozen and canned foods is dependent upon the development and improvement of commercial processing methods. It is generally known that the keeping qualities of precooked frozen meats depends on the way meats are cooked, method of packaging, type of seasoning and storage temperatures. Much of the research reported in the literature on quality of chicken meat as affected by cooking methods has been with young chickens. There are a number of papers which describe palatability of mature birds cooked with water but basic data are not available for recommending commercial cooking methods. Hanson et al. (1950) reported that the older less tender chickens of food quality could be successfully utilized in precooked frozen foods for a more flavorful product than that obtained from younger birds. Simmering or pressure-cooking was recommended to make the meat the desired degree of tenderness. Vail and Conrad (1948) described a procedure of disjointing 'Contribution from the Missouri Agricultural Experiment Station. Journal Series No. 2182 approved by Director.
hens and cooking the parts by simmering for three hours. Swickard, Harkin and Paul (1954) determined the relationship of steaming, simmering and pressure-cooking as applied to home preparations. They found that the meat of steamed and simmered hens was generally rated higher than pressure-cooking by panel evaluations, shear force and press-liquid tests. Steamed and simmered light meat was significantly more tender than pressure-cooked light meat. Woodroof and Shelor (1955) reported that chicken when cooked with moist heat may be satisfactorily frozen and stored for one year or more, while turkey may be held for from 3 to 6 months. Working with turkeys, Hanson et al. (1950) observed that the roasting method had no advantage over simmering or pressure-cooking in producing a product with a typical "roast turkey flavor" and had the disadvantage of accelerating the development of fat rancidity. In studies of red meat, Deatherage (1955) reported that the water-holding capacity of meat proteins was found to be directly related to shrinkage on cooking, drip on freezing and thawing, and tenderness. Wierbicki, Cahill and
Downloaded from http://ps.oxfordjournals.org/ at New York University on May 23, 2015
The Cooking of Fowl with Various Salts for Precooked Poultry Products 1
COOKING OF FOWL
sodium hexametaphosphate, 2.0 and 4.0% sodium tripolyphosphate and 2.0% sodium orthophosphate. The methods of cooking were boiling, simmering and pressure-cooking. Boiling represents a rolling boil for 90 min., simmering consists of cooking at 1 hr. 45 min. at 200°F. followed by an additional 45 min. at 210°F. and pressurecooking consists of cooking in an aluminum pressure-cooker at 15 p.s.i.g. for 20 min., allowing for an additional 25 min. for cooling before the lid of the pressurecooker could be removed. Since these procedures were for developing methods of processing fowl for commercial precooked frozen and canned products the birds were not sized according to weight and cooked for different time periods. Birds held at varying storage periods were grouped together for these studies. The degree of tenderness of the breast meat was measured with the Kramer shear press described by MATERIALS AND METHODS Kramer, Burkhardt and Rogers (1951) Old fowl of White Leghorn strains, 16 using the hydraulic ram adjusted to 225 to 20 months of age, obtained from the lbs. for the 3000 lb. proving ring. Samples University Poultry Farm were sacrificed, of breast meat were trimmed from either scalded, warm eviscerated, chilled in ice end of the longitudinal axis of each side water, drained, and packaged in Cryovac of the breast to fit the shearing cell, and bags. The packaged birds were frozen at then placed in the cell so that the meat — 20°F. in a blast tunnel and then stored at fibers were at an axis opposite to the cross 0°F. for 1 to 17 months before used. Birds grooves of the cell. Measurements were were removed from the freezer and thawed made of the force required to shear across in a 38°F. cooler the day before they were the grain of the meat. Separate readings to be cooked. Individual weights were were taken from both the left and right taken of the thawed eviscerated carcasses, sides of the cooked breast meat of each without giblets and necks, both before and bird, the average of the two being taken as the tenderness value of each cooked after cooking. Comparisons were made of various cook- bird. The trimmed portion was weighed ing procedures on old fowl with and with- in grams. The shear force values were calout the incorporation of salts in the water, culated as pounds per gram of sample of for cooking losses and degree of tenderness meat. A low shear value indicates tender in the breast meat. The salts initially meat. Shannon, Marion and Stadelman studied were 2.0 and 4.0% sodium chloride, (1957) reported a coefficient correlation of 0.75 and 1.50% potassium chloride, 0.60 0.86 between Kramer shear press values and 1.20% calcium chloride, 0.50 and and organoleptic panel scores of poultry 1.00% magnesium chloride, 2.0 and 4.0% meat.
Downloaded from http://ps.oxfordjournals.org/ at New York University on May 23, 2015
Deatherage (1957) found that the chlorides of sodium, potassium, calcium and magnesium when added to ground beef prior to heating increased the water-holding capacity of meat proteins when heated to 70°C. (158°F.). The juice expressed on heating was less for the calcium and magnesium chlorides than for the sodium and potassium chlorides. Magnesium chloride showed the most pronounced effect. Tims and Watts (1958) reported on the value of phosphates for red meats in decreasing cooking losses. It seemed appropriate to extend some of these findings to poultry meat. The objective of this investigation was to compare the effect of various cooking procedures on old fowl, with and without the incorporation of salts in the water, for cooking losses, degree of tenderness in the breast meat, and amount of fat in the thigh meat.
669
670
O. J. KAHLENBERG AND E. M.
RESULTS AND DISCUSSION The percentages and kinds of salts used were found to be limited because of the effect on taste of the poultry meat. When birds were cooked in either sodium hexametaphosphate or sodium orthophosphate, the pH values of the broth were on the acid side (pH 5.3 to 6.3). When either 2% sodium orthophosphate or 4% sodium hexametaphosphate were added to the cooking water the flavor of the cooked meat was rated from "slightly acid" to
"acid." In general the pH values of the broth after cooking in tap water or with the other salt solutions were on the alkaline side (range pH 7.3 to 9.1). Flavor comments for the meat cooked in tap water or the various salt solutions (except sodium chloride) were rated as "very flat." Those cooked in 4% sodium chloride solution were considered as "slightly salty" but the birds cooked in 2% sodium chloride solution were satisfactory in flavor. In view of these results the number of salt solutions were limited to those containing potassium chloride, sodium chloride and sodium tripolyphosphate. Cooking Losses. The average percent total cooking losses and Kramer shear values of fowl cooked by various methods are shown in Table 1. It was believed that the fatness of the bird was covering up expected differences due to the type and level of salt. Although the fat losses were not obtained on all of the birds, statistical treatment of the available data showed that the coefficient correlations between body weight and percent fat loss, and body weight and percent non-fat loss were for boiling 0.35 and —0.27, for simmering 0.76 and —0.23, for pressure-cooking 0.38 and 0.53 respectively. The coefficient correlations between percent fat and non-fat losses were —0.85, —0.67, and —0.36 for boiling, simmering and pressure-cooking re-
TABLE 1.—Average percent total cooking losses and Kramer shear values of fowl cooked by various methods Bo:iling Treatment
T a p water 0.75% Potassium Chloride 1.50% Potassium Chloride 2.0% Sodium Chloride 4.0% Sodium Chloride 2.0% Sodium Tripolyphosphate 4.0% Sodium Tripolyphosphate
Avg. No. carcass birds wt.
7 6 6 6 7 6 6
g1,446 1,525 1,382 1,335 1,589 1,656 1,502
Lbs. Cook- force ing p e r g . loss meat
%
34.5 37.7 40.9 40.5 40.1 39.5 40.1
* Aluminum of pressure cooker corroded due to salt.
20.20 18.36 21.29 18.12 18.13 20.73 18.15
Simmering Avg. No. carcass birds wt.
8 6 6 6 6 6 6
g1,489 1,270 1,313 1,474 1,829 1,760 1,547
Lbs. Cook- force ing p e r g . loss meat
% 37.5 36.1 40.7 39.1 39.0 37.4 37.3
18.33 19.20 21.62 19.36 15.22 17.49 18.00
Avg. No. carcass birds wt.
8 12 6 6 6 2* 2*
g. 1,486 1,435 1,283 1,568 1,450 1,153 1,509
Pressure cooking Lbs. Cook- force ing per g. loss meat
%
37.1 38.4 40.5 41.6 40.3 36.5 47.9
15.15 15.22 17.01 18.11 14.35 17.55 11.03
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Determinations of pH were made on the salt solutions and on the broth after cooking. When broth fat was measured, it was removed by means of a separatory funnel and weighed. The thigh meat without skin was removed from the bones, placed in glass jars, sealed and frozen. The frozen meat was prepared in a 0°F. room by grinding it three times in a hand-operated meat chopper. The ground samples were put back into the same glass jars and kept in the freezer locker for later analyses of fat and moisture. Moisture and fat determinations were made on duplicate samples of thigh meat by the A.O.A.C. method (19SS). Analysis of variance was calculated according to Snedecor (1956) and significance between means by Duncan's new multiple range test (19SS).
FUNK
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COOKING OF FOWL TABLE 2.—Average percent of non-fat cooking losses adjusted for variations of fat of bird Boiling
No. birds
Avg. carcass wt.
27.7
4
g1,564
28.6
1,203 1,408
30.2 25.7
4 4
1,492 1,310
27.9 26.7
4 4
1,452 2,021
28.1 23.5
4 4
1,630 1,352
26.7 27.1
6 6
1,760 1,547
25.0 26.4
No. birds
29.0
6
1,492
1,501 1,450
28.7 27.9
4 4
4 5
1,336 1,552
26.1 30.4
6 6
1,656 1,502
27.4 29.8
No. birds
T a p water
3
g1,439
0 . 7 5 % Potassium chloride 1.50% Potassium chloride
4 4
2 . 0 % Sodium chloride 4 . 0 % Sodium chloride 2 . 0 % Sodium Tripolyphosphate 4 . 0 % Sodium Tripolyphosphate
Treatment
Adj. non-fat cooking losses
%
Adj. non-fat cooking losses
%
Adj. non-fat cooking losses
%
either the "salt" or "level within the salt" were not significant. The differences due to "treatment" were significant at the 5 percent level. Students' Duncan Multiple Range test shows that simmering had significantly lower non-fat cooking losses than boiling. The non-fat cooking losses were 26.7 percent for simmering, 27.4 percent for pressure-cooking and 28.5 percent for boiling. The differences between pressurecooking and either boiling or simmering were not significant. It should be borne in mind that the cooking losses attributed to the three cooking methods could also be partially due to the length of cooking time. It is not known for example if simmering for 2j4 TABLE 3.—Analysis of variance for non-fat cooking losses adjusted for variations of fat of bird Source of variance Salt Level w/n salt Method w/n level w/n salt (Treatment) Error
d.f.
m.s.
3 3 12
5.97 16.81 15.92
67
7.72
f-value 0.36 1.06 2.06*
Total 85 * Significant at the 0.05 level. Studentized Ranges for a 5% Multiple Range Test Pressure SimTreatment Boil Cook mer Non-fat cooking loss means 28.5 27.4 26.7
Means not underscored by the same broken line are significantly different. Means which are underscored are not significantly different.
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spectively. These relationships expressed as regression coefficients were found to be — 0.67 for boiling, — 0.S6 for simmering and —0.26 for pressure-cooking. An analysis of covariance showed that the regression coefficients were significantly different from a common regression coefficient (p = .10) level. The differences between the methods of cooking after adjustment for differences in the fat of the bird were found to be significant at the 0.03 probability level. Since the relationship between percentages of fat and non-fat losses were significantly different between the cooking methods, a single regression coefficient could not be used for the entire group. Using the statistical regression coefficient for each cooking method, the percentage of non-fat losses were adjusted to account for the differences in the fatness of birds. Table 2 shows the average percent of non-fat cooking losses adjusted for variations of fat of the bird when cooked by various methods. The differences in fatness were so great in these experimental birds that they would have covered up expected differences due to the type and level of salt. The analysis of variance of the non-fat cooking losses adjusted for variations in fat content among the birds cooked by each method is shown in Table 3. It will be noted in Table 3 that the differences in non-fat cooking losses among
Pressure cooking
Simmering Avg. carcass wt.
Avg. carcass wt.
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0. J. KAHLENBERG AND E. M. TABLE 4.—Analysis of variance for Kramer shear force values
Source of variance Salt Level w / n salt Method w / n level w/n salt (Treatment) Error
d.f.
f-value
3 3 12
11.1506 51.8129 45.9533
107
12.4669
0.22 1.13 3.69*
Total 125 ** Significant at the .01 level. Studentized Ranges for a 1% Level New Multiple Range Test Pressure Treatment Boil Simmer Cook Shear Force Means 19.28 18.45 15.81
hrs. and boiling for 1}4 hrs. are equivalent from a time-temperature relationship. Kramer Shear Force Values. Analyses of variance for Kramer shear force values (Table 4) show that these values due to the salts themselves and to the "level within salt" were not significant but that "treatment" was very significant. Students' Duncan Multiple Range test showed that pressure-cooking gave significantly lower shear force values of the cooked breast meat, than did either boiling or simmering (Table 4). Although the experimental conditions were different from these studies, Swickard, Harkin and Paul (1954) reported that the simmered and steamed light meat as measured by the Warner-Bratzler shear values and palatability scores, was significantly more tender than the pressurecooked light meat, and that simmered dark meat was significantly more tender than pressure-cooked dark meat. It will also TABLE
5 . --Average
be observed in Table 4 that differences of shear force mean values of the breast meat at a result of either boiling or simmering were insignificant. Fat Content in Cooked Thigh Meat. The results recorded in Table 5 show that the percentage of fat, on a dry basis, was consistently lower when carcasses were pressure-cooked than when birds were either simmered or boiled. An analysis of variance for fat in cooked fowl thigh meat (Table 6) shows that neither the salts themselves nor the "level within salt" were significant, but that "treatment" was highly significant. Further statistical treatment of the means revealed that the thigh meat of pressurecooked carcasses was significantly lower in fat than the thigh meat of birds which were either boiled or simmered. There was no significant difference in the fat content of thigh meat when birds were cooked by either simmering or boiling. SUMMARY
Comparison of cooking losses, degree of tenderness in the breast meat, and the amount of fat in the thigh meat have been made on old fowl cooked by boiling, simmering and pressure-cooking with and without salts in the cooking water. The cooking of old fowl in the salt solutions outlined in these studies had no advantage over cooking in water with respect to adjusted non-fat cooking losses, tenderness of cooked breast meat as judged
percent fat and moisture in thigh meat of fowl cooked by various methods Boiling
Treatment
No. birds
Fat
7 6 6 6 7 6 6
/o 10.96 11.87 11.58 9.98 10.52 10.44 10.24
07
Tap water 0.75% Potassium chloride j . 5 0 % Potassium chloride 2-0% Sodium chloride 4.0% Sodium chloride 2-0% Sodium tripolyphosphate 4.0% Sodium tripolyphosphate
Moisture
%
60.85 59.71 59.39 60.49 59.61 60.55 60.08
Simmering Fat dry basis
%
27.24 29.21 28.37 25.18 25.91 26.19 25.53
No. birds
Fat
% 9.48 7.92 12.30 10.73 12.44 12.32 12.17
Moisture
%
61.32 62.25 58.86 60.50 58.88 60.01 59.61
Pressure cooking Fat dry basis
No. birds
Fat
12 6 6 6
6.78 6.17 9.12 10.55 9.76
%
24.45 20.98 29.56 26.86 30.05 30.60 29.74
%
Moisture
%
62.77 62.29 60.19 60.03 60.00
Fat dry basis
%
17.88 16.30 22.69 26.09 24.22
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Means not underscored by the same line are significantly different at the .01 level. Means which are underscored by the same line are not significantly different.
FUNK
COOKING OF FOWL TABLE 6.—Analysis of variance for fat in cooked fowl thigh meat Source of variance Salt Level Method w / n level w / n salt (Treatment) Error
d.f.
m.s.
f-value
3 3 12
162.1518 133.2552 117.5207
1.217 1.134 3.29**
107
35.7219
Total 125 ** Significant at the .01 level. Studentized Ranges of a 1% Level New Multiple Range Test Pressure Treatment Simmer Boil Cook F a t Means 27.33 26.79 20.44
by the Kramer shear test and the amount of fat in the cooked thigh meat. Significantly lower adjusted non-fat cooking losses were obtained by simmering than by boiling. Differences in adjusted non-fat cooking losses between pressure cooking and either boiling or simmering were found to be insignificant. Pressure cooking gave significantly lower Kramer shear force values of the cooked breast meat than did either boiling or simmering. Differences in shear values as a result of either boiling or simmering were not significant. The thigh meat of pressure-cooked carcasses was found to be significantly lower in fat than the thigh meat of birds which were either boiled or simmered. No significant differences in the fat content of cooked thigh meat were obtained when carcasses were cooked by either simmering or boiling. ACKNOWLEDGMENT
The authors are indebted to Dr. A. B. Stephenson and Mr. Bobby R. Jones of the Poultry Husbandry Department for their counsel and guidance in the statistical analyses of the data. Moisture and fat de-
terminations were made by the University of Missouri Experiment Station Chemical Laboratories. REFERENCES Association of Official Agricultural Chemists, 1955. Official and Tentative Methods of Analysis. 8th edition. Deatherage, F. E., 1955. Investigations on the nature of certain qualities in meat. Proceedings, Seventh Research Conference. American Meat Institute: 52-61. Duncan, D. B., 1955. Multiple range and multiple F tests. Biometrics, 11: 1-42. Hanson, H. L., H. M. Winegarden, M. B. Horton and H. Lineweaver. 19S0. Preparation and storage of frozen cooked poultry and vegetables. Food Technology, 4 : 430-434. Kramer, A., G. J. Burkhardt and H. P. Rogers, 1951. The shear press: a device for measuring food quality. Canner, 112: 34. Shannon, W. G., W. W. Marion and W. J. Stadelman, 1957. Effect of temperature and time of scalding on the tenderness of breast meat of chicken. Food Technology, 11: 284-286. Snedecor, G. W. 1956. Statistical Methods. Iowa State College Press, Ames, Iowa. Swickard, M. T., A. M. Harkin and B. J. Paul, 1954. Relationship of cooking methods, grades and frozen storage to quality of cooked mature Leghorn hens, 1954. U.S. Dept. Agr. Technical Bulletin No. 1077. Tims, M. J., and B. M. Watts, 1958. Protection of cooked meats with phosphates. Food Technology, 12: 240-243. Vail, G. E., and R. M. Conrad, 1948. Determination of palatability changes occurring in frozen poultry. Food Research, 13: 347-357. Wierbicki, E., V. R. Cahill and F. E. Deatherage, 1957. Effects of added sodium chloride, potassium chloride, calcium chloride, magnesium chloride and citric acid on meat shrinkage at 70° C. and of added sodium chloride on drip losses after freezing and thawing. Food Technology, 1 1 : 74-76. Woodroof, J. C , and E. Shelor, 1955. Keeping quality during storage of precooked frozen foods. Precooked Frozen Foods, A Symposium. Quartermaster Food and Container Institute for Armed Forces. U.S. Army.
JULY 18-20. AMERICAN POULTRY AND HATCHERY FEDERATION CONGRESS AND EXPOSITION, MUNICIPAL AUDITORIUM, MINNEAPOLIS, MINNESOTA.
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Means not underscored by the same line arc significantly different at the .01 level. Means which are underscored by the same line are not significantly different.
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