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Organoleptic and Histological Characteristics of Fresh and Frozen Stored Turkey Fed High-Density and Low-Density Rations1,2
Organoleptic and Histological Characteristics of Fresh and Frozen Stored Turkey Fed High-Density and Low-Density Rations 1,2 GRAYCE E. GOERTZ,3 GLADYS E. VAIL, 4 DOROTHY L. HARRISON AND PAUL E. SANFORD Departments of Foods and Nutrition and Poultry Husbandry, Kansas State College, Manhattan, Kansas
P
OULTRY producers recently have become interested in the use of highdensity rations. Several terms that occur in the literature such as low-fiber, highdensity, high-energy, and low-bulk are more or less synonymous terms as they refer to feeds which contain small amounts of fiber. The superiority of the high-density feeds over the low-density rations has been reported by Lloyd, Reed and Fritz (1949) and Skinner, Quisenberry and Couch (1951), who found greater growth was obtained in both chickens and turkeys when the high-density rations were fed. Birds on a high-energy ration were shown by King (1950) to lose less weight when subjected to various exercise treatments before slaughter. The importance of feed as a factor which influences the palatability of poultry has been pointed out by Carrick and Haugh (1926), Lowe (1948) and Maw (1935). Casual observers have indicated from time to time that chickens fed the high-density diets had greater 1 Part of a dissertation submitted by Grayce E. Goertz in partial fulfillment of the requirements for the degree Doctor of Philosophy. 2 Contribution No. 175, Department of Home Economics and Contribution No. 211, Department of Poultry Husbandry, Kansas Agricultural Experiment Station, Manhattan, Kansas. 3 Present Address: Department of Foods and Nutrition, Oregon State College, Corvallis, Oregon. 4 Present Address: Department of Foods and Nutrition, Purdue University, Lafayette, Indiana.
cooking losses and a different flavor from those raised on a low-density or standard poultry ration. The present study was designed to: (a) investigate the effect of high- and lowdensity rations on the organoleptic qualities of fresh and stored frozen turkey, and (b) to study certain physical and histological characteristics of fresh turkey fed the two rations. In view of the little research reported on the palatability of turkey, it was deemed advisable to investigate the differences between hens and toms and differences due to the year in which the birds were grown. Factors affecting the general acceptability of poultry meat can be explored by histological studies of muscle tissue. Hanson, Stewart and Lowe (1942) and Strandine, Koonzand Ramsbottom (1949) have reported such studies on chicken. Since the histological appearance of turkey muscle had not been reported, it was considered worthwhile to make such a study. The pectoralis major and gluteus primus muscles were chosen as representative of light and dark meat, respectively. EXPERIMENTAL METHODS
Broad Breasted Bronze turkeys were fed two types of rations in 1950 and 1951 by the Department of Poultry Husbandry at Kansas State College. One group received a low-fiber, high-density ration, the other a high-bulk, low-density
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(Received for publication October 12, 1954)
CHARACTERISTICS OF T U R K E Y M E A T TABLE 1.—High-density and low-density poult mash formulas Ingredients
Total
g.
Lowdensity
lb. 48.0 2.0 10.0 32.0 3.0
lb. 25.0 7.5 15.0 20.0 2.0 15.0 2.0 10.0
— — — 1.5 — 2.0 100.0 40.0 120.0 115.0 5.0 5.0 1.0 43.0
0.5 0.06 0.94
100.00
— 1.0 1.0 0.5 0.06 0.94
100.00
feed. Poults were placed on the diets when they were taken from the incubator and full-fed until 28 weeks of age a t which time they were killed. T h e ingredients and the respective amounts for the two rations are listed in Table 1. Twelve turkey hens were used in 1950 and 12 hens and 12 toms in 1951. T h e 36 turkeys were divided so t h a t an equal number of birds were fed high-density and low-density rations. T h e 28-week old birds were killed1, dressed, chilled for a t least 6 hours, and cut in half. One-half of each turkey was roasted fresh. The turkey halves were roasted three a t a time on the four successive days following the day of killing. They were roasted a t 300°F. (148.9°C.) to an internal temperature of 185°F. (85°C.) as indicated by a thermometer placed in the mid portion of the pectoralis major muscle, or until they had been in the oven 26 minutes per pound whichever gave the shorter cooking period. Cooking losses were determined. An experienced palatability committee scored samples from the pectoralis major and gluteus primus muscles for aroma, flavor, juiciness, and tenderness. Tenderness scores were determined
by individual judges who counted the number of chews required to completely masticate pieces of similar size. T h e individual judges assessed a numerical value according to the n u m b e r of chews. Judges received samples from the same position of the muscles a t each tasting period. A range of 10 points with 10 representing the highest quality was used to evaluate the meat. The Carver press and WarnerBratzler shearing apparatus were used to determine press fluid and shear, respectively, on the pectoralis major muscles. Steaks, one and one-half inches thick were cut from the breast and leg portions which previously had been removed from one side of each turkey and frozen. The steaks were wrapped in aluminum foil and stored in a commercial locker plant at 0°F. ( - 1 7 . 8 ° C ) . The steaks were cooked in the aluminum foil in which they were wrapped for 60 minutes at 325°F. (162.8°C.) following 0, 3, 6 and 8 months of storage. Four steaks representing as many birds were cooked at one time. One dark and one light meat steak from each bird were cooked after each storage period. T h e liquid from the cooked steak was used for the aroma evaluation. Peroxide oxygen was determined on the fat from a composite of the liquid from each lot of cooked steaks. Histological samples were taken from the posterior end of the pectoralis major and the proximal portion of the gluteus primus muscles before and after roasting the turkey halves. The samples were fixed in physiological salt and formalin solution. Longitudinal sections were cut on a freezing microtome from the preserved tissue and stained to differentiate muscle tissue, fat, and elastic and collagenous connective tissue with Harris' hemotoxylin, Herxheimer's scarlet red, French's modified Weigert's, and Van Giessen's stains, respectively. The stained sections were
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Ground yellow corn 17% Dehydrated alfalfa meal 50% M e a t and bone scraps 4 4 % Soybean oil meal 6 0 % Fish meal Wheat shorts Wheat bran Ground oats Steamed bone meal Liver meal Calcium carbonate Salt Manganous sulfate (25 g.) Vitamin mix (429 g.) Prot A (A) Delsterol (D.) Choline chloride (25%) Aurofac (Bis and aureomycin) Riboflavin Niacin Calcium pantothenate 44% Soybean oil meal
Highdensity
641
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G. E. GOERTZ, G. E. VAIL, D. L. HARRISON AND P. E. SANFORD TABLE 2.—Average weight in pounds of turkeys fed high-density and low-density rations 1951
1950 Age in weeks
Highdensity
Lowdensity
Highdensity
Lowdensity
1.09 3.63 7.87 11.57 14.18 17.05 18.49
0.99 3.38 7.67 11.44 14.52 17.43 19.49
1.06 3.58 7.13 10.88 14.90 16.31 18.68
0.96 3.37 6.92 10.33 13.88 16.15 18.52
4 8 12 16 20 24 28
high-density ration were scored slightly higher in aroma and flavor in both years RESULTS AND DISCUSSION of this study (Table 3). These birds conIn the first year of the study the poults tained larger amounts of intra-muscular on the high-density ration made a slightly fat as evaluated by a histological study of greater gain in weight during the first the tissues. Higher juiciness scores, greater half of their growing period, but were sur- volume of press fluid, and smaller perpassed by the low-density fed group when centage total cooking losses were noted in twenty weeks old (Table 2). In 1951 the turkeys on the low-density ration. Tenaverage weight of the high-density fed derness scores and amounts of total conturkeys remained slightly higher through- nective tissue were similar for all birds out the twenty-eight week period. The dif- fed each ration. Turkeys fed the lowference in all cases is small and cannot be density ration showed greater shear valconsidered to be responsible for the or- ues than those on the high-density feed. Statistically significant correlations were ganoleptic differences which occurred. found between shear values and tenderRoasted Turkey Halves. Turkeys fed the TABLE 3.—Summary of mean iifferences in data related to over-allquality of roasted turkey halves1
1951 Hens vs 1951 Toms
1950 Hens vs 1951 Hens High density vs. Low density High Aroma Flavor Juiciness Tenderness Shear—lbs./sq. in. Press Fluid ml./25 g. Total cooking loss—% 1
1950 1951
PM
GP
High Low
0.1 0.4f 0.3*
0.1
— —
—
0.6f
0.6
— —
— — —
0.3 1 —
2.It
—
—
Low 1950
— — —
0.3
— — — — —
— 1.9
0.3f 0.2
High density vs. Low density
Pectoralis major vs. gluteus primus
— — —
0.6
1.9
1951
—
0.5f
0.2 0.2
—.
— — —
0.4 0.1 2.4
—
—
—
0.2
—
—
2.0
—
Differences are listed in the columns having the higher values. * Significant at the 5 % level, f Significant at the 1% level.
Pectoralis major vs. gluteus primus Hens Toms
— 0.3f 0.4
— — —
PM
GP
0.1 0.3f 0.4
— — —
—
0.2
—
— —
0.6f
4.2
1.4t
—
—
—
10.3f
—
—
—
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placed on slides and mounted in glycerine jelly. In studying the slides the relative amounts of connective tissue and intramuscular fat in the gluteus primus and pectoralis major muscles were estimated on the basis of a numerical evaluation described by Ramsbottom, Strandine and Koonz (1945). A score of 1 indicated no fat or connective tissue; 3, 5 and 7 were used for small, medium and large amounts, respectively. Total amounts of connective tissue were obtained by adding the collagenous and elastic tissue scores.
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CHARACTERISTICS or TURKEY MEAT TABLE 4.—Correlation values for pectoralis major shear values and tenderness scores Low-density
High-density Hens 1950
Hens 1951
Toms 1951
-0.927f
-0.843*
-0.966+
Hens 1950
Hens 1951
Toms 1951
-0.988J
-0.942+
-0.632ns
ns—non-significant. * Significant at the 5 % level. f Significant at the 1% level.
than in the 1950 hens. It is possible that the 1951 hens had reached a higher degree of finish than the 1950 hens. Differences in the hens grown in the two years of this study may be accounted for, in part, by the great difference in climatic conditions during the spring and summer months of 1950 and 1951. The poults in 1950 were hatched one month later than those in 1951 and were reared in a humid, wet spring and summer. Those reared in 1951 had many more days of sunshine and dry weather. Although carefully selected, biological variation undoubtedly accounted for some of the differences observed. Average aroma scores of the pectoralis major muscle were slightly higher than those for the gluteus primus. In both the 1951 hens and toms, a highly significant flavor preference was given to the pectoralis major muscle, but mean flavor scores for the two muscles were the same for the 1950 and 1951 hens. Higher juiciness and lower tenderness scores were given to the pectoralis major than to the gluteus primus muscle. Histologically, more intramuscular fat and larger amounts of connective tissue were observed in the gluteus primus muscle. This disagrees with the work on broilers reported by Hanson, Stewart and Lowe (1942), who found that the muscles of the thigh were juicier than the pectoralis major. This difference was accounted for by a higher fat content in the thigh than in the breast. These workers used a compos-
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ness scores for the pectoralis major muscle (Table 4). No differences in appearance of the muscle fibers were noted in histological sections from turkeys fed the highdensity and low-density rations. On the whole the roasted turkey halves were similar and did not seem to vary greatly with the ration fed. In a comparison of the 1951 hens and toms, hens had better flavor, more intramuscular fat, greater juiciness, larger total volume of press fluid, and smaller percentage total cooking losses. Most of these differences were highly significant (Table 3). Toms showed slightly higher tenderness scores and somewhat lower shear values but larger amounts of total connective tissue. Ramsbottom, Strandine and Koonz (1945), although working with beef, also found that their histological ratings did not always agree with the shear values. They observed that even though large amounts of connective tissue tended to increase the shear values, other factors were involved in tenderness. The 1951 hens scored higher in aroma, flavor, and juiciness than those reared in 1950. A greater volume of press fluid, smaller percentage total cooking losses, and larger shear values were found for the 1951 hens. Statistically significant differences were found in juiciness. Flavor and press fluid differences were highly significant (Table 3). Histological study of the tissues indicated greater amounts of fat and connective tissue in the 1951 hens
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G. E. GOERTZ, G. E. VAIL, D . . . HARRISON AND P. E. SANPORD
turkeys. Lowe (1943) suggested cooking birds that came within the weight range of those used in this study between 20 and 25 minutes per pound at 300°F. (148.9°C.). Turkey Steaks. Fresh frozen turkey steaks scored lower in practically all cases when a comparison was made with roasted turkey halves. The palatability committee definitely preferred the roasted turkey to the braised steaks. However, the steaks were used for frozen storage as the smaller pieces permitted more replications within a bird. Moist heat cookery was used for the steaks to permit easier detection of an off-odor or off-flavor that developed during storage. Changes during storage probably were best reflected in the average aroma scores of the broth from the cooked steaks. Aroma values decreased with increased storage time, with those for dark steaks showing a greater drop than those for the light (Table 5). Fat from the drippings of the dark steaks generally had higher peroxide oxygen values than those from the light steaks. However, both light and dark steaks from birds fed the two rations were still acceptable at the end of eight months of storage in a commercial locker plant at 0°F. ( —17.8°C.). No differences in aroma of the steaks could be attributed to the sex of the bird or to the ration. Peroxide oxygen values for fat from turkeys fed the high-density ration generally were lower than those from the birds on the lowdensity feed (Table 5). The members of the palatability committee showed a general preference for the steaks from turkeys fed the high-density ration but this preference was slight. Histological Study. No differences in appearance of the muscle fibers were noted in histological sections from turkeys fed the high-density and low-density rations. This tended to support the results of the
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ite of thigh muscles for this comparison. Possibly the great difference in the size of the thigh and breast muscles in the turkeys as compared with those of the broilers, would account, at least in part, for the different results. The degree of doneness to which the turkey halves were cooked also offers a probable explanation for this difference in results. As has been pointed out earlier, the birds were roasted either to an internal breast temperature of 185°F. (85°G.) or for 26 minutes per pound whichever was the shorter cooking period. Time rather than internal temperature was used in almost two-thirds of the cases. The internal temperature of the birds when removed from the oven ranged from 170° to 185°F. (76.7° to 85°C.). The pectoralis major muscle was much thicker and also more protected in the roasting of the turkey halves than the gluteus primus muscle. The gluteus primus muscle always was cooked to a very well done stage; the pectoralis major muscle was done, but not well done. Alexander, Schopmeyer and Marsden (1948) reported the same difficulty in Broad Breasted Bronze turkeys which they cooked. The internal temperature of turkeys as an end point in roasting was investigated by Alexander, Schopmeyer and Lamb (1951). They reported that satisfactorily cooked meat was obtained in birds in which the internal temperature of the breast ranged between 176° to 203°F. (80° to 95°C.). The temperature of all but five of the birds in this study fell within this range; two of these were cooked to 175°F. (79.4°C.) and three to 170°F. (76.7°C.). On the other hand these investigators reported that the internal temperature of the breast muscle of birds not cooked sufficiently ranged from 160° to 180°F. (71.1° to 82.2°C.). They concluded that a specific internal temperature could not be recommended as an indication of degree of doneness in
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CHARACTERISTICS OF T U R K E Y M E A T
TABLE 5.—Average of the mean scores for aroma and peroxide oxygen values for stored frozen turkey steaks. Maximum score possible, 10
Factors
Storage time in months
1951
1950
1951
1950 Light
Dark
Light
Dark
Light
Dark
Light
Dark
9.2 6.9 6.8
8.3 8.1 7.3 7.0
8.2 7.7 6.6 6.4
8.6 7.0 7.5
8.6 6.6 6.6
8.7 8.3 6.9 7.4
8.7 8.0 6.8 6.3
0 3 6 8
8.8 7.6 7.2
Peroxide oxygen1
0 3 6 8
7 9 7
12 7 9
0 6 6 9
0 6 8 12
12 9 8
9 13 13
0 5 7 9
0 6 10 11
Expressed as ml. of 0.002N sodium thiosulfate/g. of fat in drippings.
palatability study. T h e general appearance of the muscle fibers was the same for the 1950 and 1951 hens and the toms reared in 1951. Some differences were noted between the pectoralis major and the gluteus primus muscles. I n general, the muscle fibers from the pectoralis major and gluteus primus muscles were straight with those of the cooked tissue being slightly straighter than those of the raw. The width of the muscle fibers in the gluteus primus seemed somewhat more uniform and in some cases narrower than those of the pectoralis major. T h e cross striae were more prominent in the cooked than in the uncooked tissue and were usually more distinct than the longitudinal striations in both the cooked and raw samples. Lowe (1948) reported similar results in chickens and attributed the prominence of cross striae in cooked tissue to a partial dehydration of the fibers during the cooking process. T h e cross striae of the uncooked gluteus primus muscle were more distinct than those in the cooked pectoralis major. A checkerboard effect in which the longitudinal striations were prominent in spots where the cross striae were absent was observed rather extensively in the pectoralis major
but not in the gluteus primus muscle. This effect was particularly evident with higher magnifications and was observed more in the cooked than in the raw samples. Some kinks and twists were present b u t not to any large extent. When they did occur, larger numbers were found in the raw tissue than in the corresponding cooked sample. Small amounts of zig-zag contractions were observed in several of the raw samples of the gluteus primus muscle. N o difference was noted in the number of kinks and twists occurring in the two muscles studied. This was not true of rigor nodes. T h e y occurred to a much greater extent in the gluteus primus than in the pectoralis major muscle. Oftentimes a number of nodes were present in a single fiber and appeared similar to a string of beads. On the whole, rigor nodes and internodes were more disintegrated in the cooked samples than in the raw tissue. In some of the nodes, the node proper became so swollen t h a t indentations were made in the fibers lying above and below these areas. T h e cross striae in the node were always very fine and extremely close together. Various degrees of disintegration were noted in the nodes and internodes (Figure 1). Some sarcolemma
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Aroma
1
Low-density
High-density
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G. E. GOERTZ, G. E. V A I L , D. L. H A R R I S O N AND P . E. SANFORD
FIG. 1. Rigor nodes and internodes in cooked gluteus primus muscle. Magnification X56.
of the internodal areas was broken; however, in other cases it was still intact. Much disintegration had occurred in many of the internodes. When cross striae were still present, they were quite coarse in appearance and far apart. I n some instances disintegration had occurred in the node proper particularly in the cooked tissue. On the whole the disintegration of the nodes and internodes was more extensive in the cooked sections than in the uncooked fibers. These results tend to agree with those reported by Hanson, Stewart and Lowe (1942). In their work with broilers they found that the thigh muscles remained in rigor longer than the breast muscles. Histological changes were correspondingly slower in the thigh than in the breast. Disintegration fissures occurred rather extensively in the gluteus primus muscle. They occurred to a much greater extent in the cooked than in the uncooked fibers.
Little difference in the appearance of the intramuscular fat was noted between the cooked and raw samples of either the pectoralis major or gluteus primus muscles. In general, most of the cells were small to medium in size and packed full of fat. Some empty fat cells were observed, but these occurred to a greater extent in the cooked than in the raw tissues. The distribution of fat was somewhat different in the gluteus primus from that in the pectoralis major muscle. The fat in the gluteus primus muscle occurred in small groups of cells, well distributed throughout the entire muscle. Large clusters of fat cells, concentrated in a few areas, were characteristic of the fat distribution in the pectoralis muscle. On the whole, greater quantities of fat were observed in the gluteus primus muscle than in the pectoralis major. The greatest histological differences in the connective tissue were noted between the raw and the cooked samples. This was particularly true of the collagenous connective tissue. In the raw samples, it appeared in groups of wavy fibers in which fat cells were often embedded (Figure 2).
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This type of disintegration rarely occurred in the pectoralis major muscle. A medium number of disintegration strips occurred in the cooked pectoralis major muscle; some were noted in the raw samples. Both intact and broken sarcolemma were noted in the disintegration strips. Some overall disintegration was observed in the cooked gluteus primus tissue but this was not found in any of the sections of the raw gluteus primus fibers. Fewer breaks occurred in the raw and cooked tissue of the gluteus primus muscle than were present in the pectoralis major. I t was interesting to note that a rather general iridescence occurred in most of the stained cooked tissue from both the gluteus primus and pectoralis major muscles.
CHARACTERISTICS OF T U R K E Y M E A T
647
Elastic connective tissue was found mainly in the blood vessels which were often surrounded by fat cells. Some needlelike rods of elastic fibers were observed in collagenous tissue of raw and cooked samples of the pectoralis major and gluteus primus muscles. These were always present in small amounts. FIG. 2. Upper: Uncooked gluteus primus muscle with a wide band of collagenous connective tissue near the center. The dark spots are precipitated stain. Lower: Disintegration strips and breaks in cooked pectoralis major muscle. Note the swollen, irregularly shaped and granulated collagenous connective tissue in the lower half of the photomicrograph. Magnification X56.
SUMMARY
Broad Breasted Bronze turkeys were fed two types of rations; one group received a high-density, low-fiber feed and the other a low-density, high-bulk ration. Only turkey hens were used the first year of the study, but a comparison of both
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A few long wavy fibers were present between individual muscle cells, but denser masses occurred between the bundles of fibers. Upon cooking, some of the collagenous connective tissue fibers became swollen and appeared irregular in shape. More extensive changes were observed in other portions of the collagenous tissue where it appeared as a fine granular network. T h e swollen collagenous connective tissue which was changed in cooking, occurred mainly between bundles of fibers, and appeared to lie on top of the muscle fibers in some places. Some granular collagenous tissue occurred between the bundles; but when connective tissue was observed between the individual muscle fibers, it was usually the granular type. Elastic connective tissue in the cooked meat appeared similar to that in the raw tissue. Ramsbottom, Strandine and Koonz (1945), although working with beef, also reported a pronounced change in the appearance of collagenous connective tissue and little change in the elastic tissue with cooking. They described the cooked collagenous fibers as enlarged and irregular in shape. Lowe (1948) observed a granular appearance in cooked collagenous tissue of chicken muscle.
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NEWS AND NOTES REFERENCES Alexander, L. M., G. E. Schopmeyer and J. C. Lamb, 1951. Turkey temperature as the end point in roasting. Poultry Sci. 30: 520-524. Alexander, L. M., G. E. Schopmeyer and S. J. Marsden, 1948. Yield of cooked edible portion of young roasted turkey. Poultry Sci. 27: 579-587. Carrick, C. W., and M. S. Hauge, 1926. The effect of cod liver oil upon flavor in poultry meat. Poultry Sci. 5: 213-215. Hanson, H. L., G. F. Stewart and B. Lowe, 1942. Palatability and histological changes occurring in New York dressed broilers held at 1.7°C. (35°F.). Food Research, 7: 148-160. King, R. A., 1950. Why hauling shrinks vary. U. S. Egg Poultry Mag. 56: 14-15. Lloyd, M. D., C. A. Reed and J. C. Fritz, 1949. Experiences with high protein diets for chicks and poults. Poultry Sci. 28: 69-74. Lowe, B., 1943. Experimental Cookery from the Chemical and Physical Standpoint. 3rd Ed., John Wiley, New York. p. 262. Lowe, B., 1948. Factors affecting the palatability of poultry with emphasis on histological post-mortem changes. Advances in Food Research, 1: 203-256. Maw, W. A., 1935. How quality in poultry meat is affected by the distribution of fat in the carcass. U. S. Egg Poultry Mag. 41: 32-36. Ramsbottom, J. M., E. J. Strandine and C. H. Koonz, 1945. Comparative tenderness of representative beef muscles. Food Research, 10: 497509. Skinner, J. L., J. H. Quisenberry and J. R. Couch, 1951. High-efficiency and APF concentrate in the ration of the laying fowl. Poultry Sci. 30: 319-324. Strandine, E. J., C. H. Koonz and J. M. Ramsbottom, 1949. A study of variations in muscles of beef and chickens. J. Animal Sci. 8: 483-494.
NEWS AND NOTES {Continued from page 639) the National Poultry Diploma Examinations Board and has served as Examiner for the Board. Mr. Harvey has served the poultry industry for 25 years as an officer of the Poultry Association of Great Britain. He has been its General Secretary for 15 years. He is a Devonian and on leaving school spent some time as a student on a farm in that county. Later he entered the animal feedingstuffs trade and
was engaged in it for about 10 years, leaving it to join the Poultry Association of Great Britain in an administrative and advisory capacity. OHIO NOTES E. L. Dakan has resigned as Chairman of the Department of Poultry Husbandry, the Ohio State University, Columbus, after serving in that capacity for over 30 years. The Board of Trustees, in accept-
(Continued on page 654)
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hens and toms was made the second year. One-half of each turkey was roasted fresh and samples from the pectoralis major and gluteus primus muscles were scored by a palatability committee. A histological study of muscle fibers, fat distribution, and types of connective tissue also was made on the raw and cooked samples of these two muscles. A slight but not significant preference was given to the roasted turkey and braised turkey steaks from birds fed the high-density ration. Roasted turkey hens had higher scores for flavor, juiciness, and intramuscular fat and smaller percentage cooking losses than roasted toms. There was a statistically significant correlation between the shear values and tenderness scores of the pectoralis major muscle from the roasted turkey halves. Turkey steaks from birds on both of the rations were still acceptable after 8 months of storage in a commercial locker plant at 0°F. (-17.8°C). Quality of the dark steaks decreased more during the eight months storage than that of the light steaks. Histologically, the pectoralis major muscle fibers showed a fragility resembling a worn textile, disintegration strips, and some breaks. The gluteus primus contained more rigor nodes and fewer breaks but also had some disintegration strips and fissures.
P
OULTRY producers recently have become interested in the use of highdensity rations. Several terms that occur in the literature such as low-fiber, highdensity, high-energy, and low-bulk are more or less synonymous terms as they refer to feeds which contain small amounts of fiber. The superiority of the high-density feeds over the low-density rations has been reported by Lloyd, Reed and Fritz (1949) and Skinner, Quisenberry and Couch (1951), who found greater growth was obtained in both chickens and turkeys when the high-density rations were fed. Birds on a high-energy ration were shown by King (1950) to lose less weight when subjected to various exercise treatments before slaughter. The importance of feed as a factor which influences the palatability of poultry has been pointed out by Carrick and Haugh (1926), Lowe (1948) and Maw (1935). Casual observers have indicated from time to time that chickens fed the high-density diets had greater 1 Part of a dissertation submitted by Grayce E. Goertz in partial fulfillment of the requirements for the degree Doctor of Philosophy. 2 Contribution No. 175, Department of Home Economics and Contribution No. 211, Department of Poultry Husbandry, Kansas Agricultural Experiment Station, Manhattan, Kansas. 3 Present Address: Department of Foods and Nutrition, Oregon State College, Corvallis, Oregon. 4 Present Address: Department of Foods and Nutrition, Purdue University, Lafayette, Indiana.
cooking losses and a different flavor from those raised on a low-density or standard poultry ration. The present study was designed to: (a) investigate the effect of high- and lowdensity rations on the organoleptic qualities of fresh and stored frozen turkey, and (b) to study certain physical and histological characteristics of fresh turkey fed the two rations. In view of the little research reported on the palatability of turkey, it was deemed advisable to investigate the differences between hens and toms and differences due to the year in which the birds were grown. Factors affecting the general acceptability of poultry meat can be explored by histological studies of muscle tissue. Hanson, Stewart and Lowe (1942) and Strandine, Koonzand Ramsbottom (1949) have reported such studies on chicken. Since the histological appearance of turkey muscle had not been reported, it was considered worthwhile to make such a study. The pectoralis major and gluteus primus muscles were chosen as representative of light and dark meat, respectively. EXPERIMENTAL METHODS
Broad Breasted Bronze turkeys were fed two types of rations in 1950 and 1951 by the Department of Poultry Husbandry at Kansas State College. One group received a low-fiber, high-density ration, the other a high-bulk, low-density
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(Received for publication October 12, 1954)
CHARACTERISTICS OF T U R K E Y M E A T TABLE 1.—High-density and low-density poult mash formulas Ingredients
Total
g.
Lowdensity
lb. 48.0 2.0 10.0 32.0 3.0
lb. 25.0 7.5 15.0 20.0 2.0 15.0 2.0 10.0
— — — 1.5 — 2.0 100.0 40.0 120.0 115.0 5.0 5.0 1.0 43.0
0.5 0.06 0.94
100.00
— 1.0 1.0 0.5 0.06 0.94
100.00
feed. Poults were placed on the diets when they were taken from the incubator and full-fed until 28 weeks of age a t which time they were killed. T h e ingredients and the respective amounts for the two rations are listed in Table 1. Twelve turkey hens were used in 1950 and 12 hens and 12 toms in 1951. T h e 36 turkeys were divided so t h a t an equal number of birds were fed high-density and low-density rations. T h e 28-week old birds were killed1, dressed, chilled for a t least 6 hours, and cut in half. One-half of each turkey was roasted fresh. The turkey halves were roasted three a t a time on the four successive days following the day of killing. They were roasted a t 300°F. (148.9°C.) to an internal temperature of 185°F. (85°C.) as indicated by a thermometer placed in the mid portion of the pectoralis major muscle, or until they had been in the oven 26 minutes per pound whichever gave the shorter cooking period. Cooking losses were determined. An experienced palatability committee scored samples from the pectoralis major and gluteus primus muscles for aroma, flavor, juiciness, and tenderness. Tenderness scores were determined
by individual judges who counted the number of chews required to completely masticate pieces of similar size. T h e individual judges assessed a numerical value according to the n u m b e r of chews. Judges received samples from the same position of the muscles a t each tasting period. A range of 10 points with 10 representing the highest quality was used to evaluate the meat. The Carver press and WarnerBratzler shearing apparatus were used to determine press fluid and shear, respectively, on the pectoralis major muscles. Steaks, one and one-half inches thick were cut from the breast and leg portions which previously had been removed from one side of each turkey and frozen. The steaks were wrapped in aluminum foil and stored in a commercial locker plant at 0°F. ( - 1 7 . 8 ° C ) . The steaks were cooked in the aluminum foil in which they were wrapped for 60 minutes at 325°F. (162.8°C.) following 0, 3, 6 and 8 months of storage. Four steaks representing as many birds were cooked at one time. One dark and one light meat steak from each bird were cooked after each storage period. T h e liquid from the cooked steak was used for the aroma evaluation. Peroxide oxygen was determined on the fat from a composite of the liquid from each lot of cooked steaks. Histological samples were taken from the posterior end of the pectoralis major and the proximal portion of the gluteus primus muscles before and after roasting the turkey halves. The samples were fixed in physiological salt and formalin solution. Longitudinal sections were cut on a freezing microtome from the preserved tissue and stained to differentiate muscle tissue, fat, and elastic and collagenous connective tissue with Harris' hemotoxylin, Herxheimer's scarlet red, French's modified Weigert's, and Van Giessen's stains, respectively. The stained sections were
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Ground yellow corn 17% Dehydrated alfalfa meal 50% M e a t and bone scraps 4 4 % Soybean oil meal 6 0 % Fish meal Wheat shorts Wheat bran Ground oats Steamed bone meal Liver meal Calcium carbonate Salt Manganous sulfate (25 g.) Vitamin mix (429 g.) Prot A (A) Delsterol (D.) Choline chloride (25%) Aurofac (Bis and aureomycin) Riboflavin Niacin Calcium pantothenate 44% Soybean oil meal
Highdensity
641
642
G. E. GOERTZ, G. E. VAIL, D. L. HARRISON AND P. E. SANFORD TABLE 2.—Average weight in pounds of turkeys fed high-density and low-density rations 1951
1950 Age in weeks
Highdensity
Lowdensity
Highdensity
Lowdensity
1.09 3.63 7.87 11.57 14.18 17.05 18.49
0.99 3.38 7.67 11.44 14.52 17.43 19.49
1.06 3.58 7.13 10.88 14.90 16.31 18.68
0.96 3.37 6.92 10.33 13.88 16.15 18.52
4 8 12 16 20 24 28
high-density ration were scored slightly higher in aroma and flavor in both years RESULTS AND DISCUSSION of this study (Table 3). These birds conIn the first year of the study the poults tained larger amounts of intra-muscular on the high-density ration made a slightly fat as evaluated by a histological study of greater gain in weight during the first the tissues. Higher juiciness scores, greater half of their growing period, but were sur- volume of press fluid, and smaller perpassed by the low-density fed group when centage total cooking losses were noted in twenty weeks old (Table 2). In 1951 the turkeys on the low-density ration. Tenaverage weight of the high-density fed derness scores and amounts of total conturkeys remained slightly higher through- nective tissue were similar for all birds out the twenty-eight week period. The dif- fed each ration. Turkeys fed the lowference in all cases is small and cannot be density ration showed greater shear valconsidered to be responsible for the or- ues than those on the high-density feed. Statistically significant correlations were ganoleptic differences which occurred. found between shear values and tenderRoasted Turkey Halves. Turkeys fed the TABLE 3.—Summary of mean iifferences in data related to over-allquality of roasted turkey halves1
1951 Hens vs 1951 Toms
1950 Hens vs 1951 Hens High density vs. Low density High Aroma Flavor Juiciness Tenderness Shear—lbs./sq. in. Press Fluid ml./25 g. Total cooking loss—% 1
1950 1951
PM
GP
High Low
0.1 0.4f 0.3*
0.1
— —
—
0.6f
0.6
— —
— — —
0.3 1 —
2.It
—
—
Low 1950
— — —
0.3
— — — — —
— 1.9
0.3f 0.2
High density vs. Low density
Pectoralis major vs. gluteus primus
— — —
0.6
1.9
1951
—
0.5f
0.2 0.2
—.
— — —
0.4 0.1 2.4
—
—
—
0.2
—
—
2.0
—
Differences are listed in the columns having the higher values. * Significant at the 5 % level, f Significant at the 1% level.
Pectoralis major vs. gluteus primus Hens Toms
— 0.3f 0.4
— — —
PM
GP
0.1 0.3f 0.4
— — —
—
0.2
—
— —
0.6f
4.2
1.4t
—
—
—
10.3f
—
—
—
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placed on slides and mounted in glycerine jelly. In studying the slides the relative amounts of connective tissue and intramuscular fat in the gluteus primus and pectoralis major muscles were estimated on the basis of a numerical evaluation described by Ramsbottom, Strandine and Koonz (1945). A score of 1 indicated no fat or connective tissue; 3, 5 and 7 were used for small, medium and large amounts, respectively. Total amounts of connective tissue were obtained by adding the collagenous and elastic tissue scores.
643
CHARACTERISTICS or TURKEY MEAT TABLE 4.—Correlation values for pectoralis major shear values and tenderness scores Low-density
High-density Hens 1950
Hens 1951
Toms 1951
-0.927f
-0.843*
-0.966+
Hens 1950
Hens 1951
Toms 1951
-0.988J
-0.942+
-0.632ns
ns—non-significant. * Significant at the 5 % level. f Significant at the 1% level.
than in the 1950 hens. It is possible that the 1951 hens had reached a higher degree of finish than the 1950 hens. Differences in the hens grown in the two years of this study may be accounted for, in part, by the great difference in climatic conditions during the spring and summer months of 1950 and 1951. The poults in 1950 were hatched one month later than those in 1951 and were reared in a humid, wet spring and summer. Those reared in 1951 had many more days of sunshine and dry weather. Although carefully selected, biological variation undoubtedly accounted for some of the differences observed. Average aroma scores of the pectoralis major muscle were slightly higher than those for the gluteus primus. In both the 1951 hens and toms, a highly significant flavor preference was given to the pectoralis major muscle, but mean flavor scores for the two muscles were the same for the 1950 and 1951 hens. Higher juiciness and lower tenderness scores were given to the pectoralis major than to the gluteus primus muscle. Histologically, more intramuscular fat and larger amounts of connective tissue were observed in the gluteus primus muscle. This disagrees with the work on broilers reported by Hanson, Stewart and Lowe (1942), who found that the muscles of the thigh were juicier than the pectoralis major. This difference was accounted for by a higher fat content in the thigh than in the breast. These workers used a compos-
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ness scores for the pectoralis major muscle (Table 4). No differences in appearance of the muscle fibers were noted in histological sections from turkeys fed the highdensity and low-density rations. On the whole the roasted turkey halves were similar and did not seem to vary greatly with the ration fed. In a comparison of the 1951 hens and toms, hens had better flavor, more intramuscular fat, greater juiciness, larger total volume of press fluid, and smaller percentage total cooking losses. Most of these differences were highly significant (Table 3). Toms showed slightly higher tenderness scores and somewhat lower shear values but larger amounts of total connective tissue. Ramsbottom, Strandine and Koonz (1945), although working with beef, also found that their histological ratings did not always agree with the shear values. They observed that even though large amounts of connective tissue tended to increase the shear values, other factors were involved in tenderness. The 1951 hens scored higher in aroma, flavor, and juiciness than those reared in 1950. A greater volume of press fluid, smaller percentage total cooking losses, and larger shear values were found for the 1951 hens. Statistically significant differences were found in juiciness. Flavor and press fluid differences were highly significant (Table 3). Histological study of the tissues indicated greater amounts of fat and connective tissue in the 1951 hens
644
G. E. GOERTZ, G. E. VAIL, D . . . HARRISON AND P. E. SANPORD
turkeys. Lowe (1943) suggested cooking birds that came within the weight range of those used in this study between 20 and 25 minutes per pound at 300°F. (148.9°C.). Turkey Steaks. Fresh frozen turkey steaks scored lower in practically all cases when a comparison was made with roasted turkey halves. The palatability committee definitely preferred the roasted turkey to the braised steaks. However, the steaks were used for frozen storage as the smaller pieces permitted more replications within a bird. Moist heat cookery was used for the steaks to permit easier detection of an off-odor or off-flavor that developed during storage. Changes during storage probably were best reflected in the average aroma scores of the broth from the cooked steaks. Aroma values decreased with increased storage time, with those for dark steaks showing a greater drop than those for the light (Table 5). Fat from the drippings of the dark steaks generally had higher peroxide oxygen values than those from the light steaks. However, both light and dark steaks from birds fed the two rations were still acceptable at the end of eight months of storage in a commercial locker plant at 0°F. ( —17.8°C.). No differences in aroma of the steaks could be attributed to the sex of the bird or to the ration. Peroxide oxygen values for fat from turkeys fed the high-density ration generally were lower than those from the birds on the lowdensity feed (Table 5). The members of the palatability committee showed a general preference for the steaks from turkeys fed the high-density ration but this preference was slight. Histological Study. No differences in appearance of the muscle fibers were noted in histological sections from turkeys fed the high-density and low-density rations. This tended to support the results of the
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ite of thigh muscles for this comparison. Possibly the great difference in the size of the thigh and breast muscles in the turkeys as compared with those of the broilers, would account, at least in part, for the different results. The degree of doneness to which the turkey halves were cooked also offers a probable explanation for this difference in results. As has been pointed out earlier, the birds were roasted either to an internal breast temperature of 185°F. (85°G.) or for 26 minutes per pound whichever was the shorter cooking period. Time rather than internal temperature was used in almost two-thirds of the cases. The internal temperature of the birds when removed from the oven ranged from 170° to 185°F. (76.7° to 85°C.). The pectoralis major muscle was much thicker and also more protected in the roasting of the turkey halves than the gluteus primus muscle. The gluteus primus muscle always was cooked to a very well done stage; the pectoralis major muscle was done, but not well done. Alexander, Schopmeyer and Marsden (1948) reported the same difficulty in Broad Breasted Bronze turkeys which they cooked. The internal temperature of turkeys as an end point in roasting was investigated by Alexander, Schopmeyer and Lamb (1951). They reported that satisfactorily cooked meat was obtained in birds in which the internal temperature of the breast ranged between 176° to 203°F. (80° to 95°C.). The temperature of all but five of the birds in this study fell within this range; two of these were cooked to 175°F. (79.4°C.) and three to 170°F. (76.7°C.). On the other hand these investigators reported that the internal temperature of the breast muscle of birds not cooked sufficiently ranged from 160° to 180°F. (71.1° to 82.2°C.). They concluded that a specific internal temperature could not be recommended as an indication of degree of doneness in
645
CHARACTERISTICS OF T U R K E Y M E A T
TABLE 5.—Average of the mean scores for aroma and peroxide oxygen values for stored frozen turkey steaks. Maximum score possible, 10
Factors
Storage time in months
1951
1950
1951
1950 Light
Dark
Light
Dark
Light
Dark
Light
Dark
9.2 6.9 6.8
8.3 8.1 7.3 7.0
8.2 7.7 6.6 6.4
8.6 7.0 7.5
8.6 6.6 6.6
8.7 8.3 6.9 7.4
8.7 8.0 6.8 6.3
0 3 6 8
8.8 7.6 7.2
Peroxide oxygen1
0 3 6 8
7 9 7
12 7 9
0 6 6 9
0 6 8 12
12 9 8
9 13 13
0 5 7 9
0 6 10 11
Expressed as ml. of 0.002N sodium thiosulfate/g. of fat in drippings.
palatability study. T h e general appearance of the muscle fibers was the same for the 1950 and 1951 hens and the toms reared in 1951. Some differences were noted between the pectoralis major and the gluteus primus muscles. I n general, the muscle fibers from the pectoralis major and gluteus primus muscles were straight with those of the cooked tissue being slightly straighter than those of the raw. The width of the muscle fibers in the gluteus primus seemed somewhat more uniform and in some cases narrower than those of the pectoralis major. T h e cross striae were more prominent in the cooked than in the uncooked tissue and were usually more distinct than the longitudinal striations in both the cooked and raw samples. Lowe (1948) reported similar results in chickens and attributed the prominence of cross striae in cooked tissue to a partial dehydration of the fibers during the cooking process. T h e cross striae of the uncooked gluteus primus muscle were more distinct than those in the cooked pectoralis major. A checkerboard effect in which the longitudinal striations were prominent in spots where the cross striae were absent was observed rather extensively in the pectoralis major
but not in the gluteus primus muscle. This effect was particularly evident with higher magnifications and was observed more in the cooked than in the raw samples. Some kinks and twists were present b u t not to any large extent. When they did occur, larger numbers were found in the raw tissue than in the corresponding cooked sample. Small amounts of zig-zag contractions were observed in several of the raw samples of the gluteus primus muscle. N o difference was noted in the number of kinks and twists occurring in the two muscles studied. This was not true of rigor nodes. T h e y occurred to a much greater extent in the gluteus primus than in the pectoralis major muscle. Oftentimes a number of nodes were present in a single fiber and appeared similar to a string of beads. On the whole, rigor nodes and internodes were more disintegrated in the cooked samples than in the raw tissue. In some of the nodes, the node proper became so swollen t h a t indentations were made in the fibers lying above and below these areas. T h e cross striae in the node were always very fine and extremely close together. Various degrees of disintegration were noted in the nodes and internodes (Figure 1). Some sarcolemma
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Aroma
1
Low-density
High-density
646
G. E. GOERTZ, G. E. V A I L , D. L. H A R R I S O N AND P . E. SANFORD
FIG. 1. Rigor nodes and internodes in cooked gluteus primus muscle. Magnification X56.
of the internodal areas was broken; however, in other cases it was still intact. Much disintegration had occurred in many of the internodes. When cross striae were still present, they were quite coarse in appearance and far apart. I n some instances disintegration had occurred in the node proper particularly in the cooked tissue. On the whole the disintegration of the nodes and internodes was more extensive in the cooked sections than in the uncooked fibers. These results tend to agree with those reported by Hanson, Stewart and Lowe (1942). In their work with broilers they found that the thigh muscles remained in rigor longer than the breast muscles. Histological changes were correspondingly slower in the thigh than in the breast. Disintegration fissures occurred rather extensively in the gluteus primus muscle. They occurred to a much greater extent in the cooked than in the uncooked fibers.
Little difference in the appearance of the intramuscular fat was noted between the cooked and raw samples of either the pectoralis major or gluteus primus muscles. In general, most of the cells were small to medium in size and packed full of fat. Some empty fat cells were observed, but these occurred to a greater extent in the cooked than in the raw tissues. The distribution of fat was somewhat different in the gluteus primus from that in the pectoralis major muscle. The fat in the gluteus primus muscle occurred in small groups of cells, well distributed throughout the entire muscle. Large clusters of fat cells, concentrated in a few areas, were characteristic of the fat distribution in the pectoralis muscle. On the whole, greater quantities of fat were observed in the gluteus primus muscle than in the pectoralis major. The greatest histological differences in the connective tissue were noted between the raw and the cooked samples. This was particularly true of the collagenous connective tissue. In the raw samples, it appeared in groups of wavy fibers in which fat cells were often embedded (Figure 2).
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This type of disintegration rarely occurred in the pectoralis major muscle. A medium number of disintegration strips occurred in the cooked pectoralis major muscle; some were noted in the raw samples. Both intact and broken sarcolemma were noted in the disintegration strips. Some overall disintegration was observed in the cooked gluteus primus tissue but this was not found in any of the sections of the raw gluteus primus fibers. Fewer breaks occurred in the raw and cooked tissue of the gluteus primus muscle than were present in the pectoralis major. I t was interesting to note that a rather general iridescence occurred in most of the stained cooked tissue from both the gluteus primus and pectoralis major muscles.
CHARACTERISTICS OF T U R K E Y M E A T
647
Elastic connective tissue was found mainly in the blood vessels which were often surrounded by fat cells. Some needlelike rods of elastic fibers were observed in collagenous tissue of raw and cooked samples of the pectoralis major and gluteus primus muscles. These were always present in small amounts. FIG. 2. Upper: Uncooked gluteus primus muscle with a wide band of collagenous connective tissue near the center. The dark spots are precipitated stain. Lower: Disintegration strips and breaks in cooked pectoralis major muscle. Note the swollen, irregularly shaped and granulated collagenous connective tissue in the lower half of the photomicrograph. Magnification X56.
SUMMARY
Broad Breasted Bronze turkeys were fed two types of rations; one group received a high-density, low-fiber feed and the other a low-density, high-bulk ration. Only turkey hens were used the first year of the study, but a comparison of both
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A few long wavy fibers were present between individual muscle cells, but denser masses occurred between the bundles of fibers. Upon cooking, some of the collagenous connective tissue fibers became swollen and appeared irregular in shape. More extensive changes were observed in other portions of the collagenous tissue where it appeared as a fine granular network. T h e swollen collagenous connective tissue which was changed in cooking, occurred mainly between bundles of fibers, and appeared to lie on top of the muscle fibers in some places. Some granular collagenous tissue occurred between the bundles; but when connective tissue was observed between the individual muscle fibers, it was usually the granular type. Elastic connective tissue in the cooked meat appeared similar to that in the raw tissue. Ramsbottom, Strandine and Koonz (1945), although working with beef, also reported a pronounced change in the appearance of collagenous connective tissue and little change in the elastic tissue with cooking. They described the cooked collagenous fibers as enlarged and irregular in shape. Lowe (1948) observed a granular appearance in cooked collagenous tissue of chicken muscle.
648
NEWS AND NOTES REFERENCES Alexander, L. M., G. E. Schopmeyer and J. C. Lamb, 1951. Turkey temperature as the end point in roasting. Poultry Sci. 30: 520-524. Alexander, L. M., G. E. Schopmeyer and S. J. Marsden, 1948. Yield of cooked edible portion of young roasted turkey. Poultry Sci. 27: 579-587. Carrick, C. W., and M. S. Hauge, 1926. The effect of cod liver oil upon flavor in poultry meat. Poultry Sci. 5: 213-215. Hanson, H. L., G. F. Stewart and B. Lowe, 1942. Palatability and histological changes occurring in New York dressed broilers held at 1.7°C. (35°F.). Food Research, 7: 148-160. King, R. A., 1950. Why hauling shrinks vary. U. S. Egg Poultry Mag. 56: 14-15. Lloyd, M. D., C. A. Reed and J. C. Fritz, 1949. Experiences with high protein diets for chicks and poults. Poultry Sci. 28: 69-74. Lowe, B., 1943. Experimental Cookery from the Chemical and Physical Standpoint. 3rd Ed., John Wiley, New York. p. 262. Lowe, B., 1948. Factors affecting the palatability of poultry with emphasis on histological post-mortem changes. Advances in Food Research, 1: 203-256. Maw, W. A., 1935. How quality in poultry meat is affected by the distribution of fat in the carcass. U. S. Egg Poultry Mag. 41: 32-36. Ramsbottom, J. M., E. J. Strandine and C. H. Koonz, 1945. Comparative tenderness of representative beef muscles. Food Research, 10: 497509. Skinner, J. L., J. H. Quisenberry and J. R. Couch, 1951. High-efficiency and APF concentrate in the ration of the laying fowl. Poultry Sci. 30: 319-324. Strandine, E. J., C. H. Koonz and J. M. Ramsbottom, 1949. A study of variations in muscles of beef and chickens. J. Animal Sci. 8: 483-494.
NEWS AND NOTES {Continued from page 639) the National Poultry Diploma Examinations Board and has served as Examiner for the Board. Mr. Harvey has served the poultry industry for 25 years as an officer of the Poultry Association of Great Britain. He has been its General Secretary for 15 years. He is a Devonian and on leaving school spent some time as a student on a farm in that county. Later he entered the animal feedingstuffs trade and
was engaged in it for about 10 years, leaving it to join the Poultry Association of Great Britain in an administrative and advisory capacity. OHIO NOTES E. L. Dakan has resigned as Chairman of the Department of Poultry Husbandry, the Ohio State University, Columbus, after serving in that capacity for over 30 years. The Board of Trustees, in accept-
(Continued on page 654)
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hens and toms was made the second year. One-half of each turkey was roasted fresh and samples from the pectoralis major and gluteus primus muscles were scored by a palatability committee. A histological study of muscle fibers, fat distribution, and types of connective tissue also was made on the raw and cooked samples of these two muscles. A slight but not significant preference was given to the roasted turkey and braised turkey steaks from birds fed the high-density ration. Roasted turkey hens had higher scores for flavor, juiciness, and intramuscular fat and smaller percentage cooking losses than roasted toms. There was a statistically significant correlation between the shear values and tenderness scores of the pectoralis major muscle from the roasted turkey halves. Turkey steaks from birds on both of the rations were still acceptable after 8 months of storage in a commercial locker plant at 0°F. (-17.8°C). Quality of the dark steaks decreased more during the eight months storage than that of the light steaks. Histologically, the pectoralis major muscle fibers showed a fragility resembling a worn textile, disintegration strips, and some breaks. The gluteus primus contained more rigor nodes and fewer breaks but also had some disintegration strips and fissures.