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Sensory, Physical, and Microbiological Comparison of Brine-Chilled, Water-chilled, and Hot-packaged (No Chill) Broilers1
MARKETING AND PRODUCTS Sensory, Physical, and Microbiological Comparison of Brine-Chilled, Water-chilled, and Hot-packaged (No Chill) Broilers1 D. M. JANKY 2 , A. S. ARAFA 2 , J. L. OBLINGER 3 , J. A. KOBURGER 3 , and D. L. FLETCHER 2 Florida Agricultural Experiment Stations, University of Florida, Gainesville, Florida 32611 (Received for publication July 8, 1977)
INTRODUCTION Arafa ( 1 9 7 5 ) r e p o r t e d t h a t hot-packaging of p o u l t r y greatly reduced drip formation a n d increased shelf-life when c o m p a r e d with slushice-chilled p o u l t r y . This a u t h o r also observed higher cooking yield and b e t t e r flavor scores for hot-packaged birds. T h e a c t i o n of salts, such as p o l y p h o s p h a t e s , on t h e water holding capacity of p o u l t r y m e a t is well d o c u m e n t e d (Klose et ai, 1 9 6 3 , Brotsky, 1976). Treating chicken muscle with NaCl in c o m b i n a t i o n with p o l y p h o s p h a t e s has been observed t o increase water holding capacity and decrease shrink (Shults and Wierbicki, 1 9 7 3 ) . T h e immersion of ready-to-cook broilers in NaCl solutions prior t o smoking has been shown to increase t h e tenderness of t h e m e a t from these birds (Oblinger et ai, 1 9 7 6 ) . These a u t h o r s further observed a slight toughening effect w h e n carcasses were immersed in water for similar t i m e s before smoking. G a r d n e r and Atkinson ( 1 9 6 7 ) chilled broiler carcasses in varying solutions of NaCl and observed little
1
Florida Agr. Exp. Stas. Journal Series No. 613. Department of Poultry Science, University of Florida, Gainesville, Florida 32611. 3 Department of Food Science, University of Florida, Gainesville, Florida 32611. 2
1978 Poultry Sci 57:417-421
effect on the physical characteristics of t h e carcasses. In view of these findings, it was theorized t h a t salt-brine chilling as a processing t e c h n i q u e might influence p o u l t r y m e a t tenderness and quality. T h e purpose of this e x p e r i m e n t was t o c o m p a r e various physical, sensory, and microbiological characteristics of brine-chilled, slushice-chilled (control), and hot-packaged (negative control with n o chill) carcasses. EXPERIMENTAL PROCEDURE Forty-five male C o b b color-sexed broilers 8 weeks-of age were slaughtered b y exsanguination, subscalded (60 C for 45 sec), and picked in a r o t a r y d r u m picker. After evisceration t h e carcasses were rinsed and weighed (pre-chill) and assigned t o one of the following three chilling procedures: hot-packaged (no chill), overnight chilling in ice slush (1 C), or overnight chilling in a 5% NaCl ice slush (—1 C). T h e ratio of chill water volume t o bird w t was k e p t c o n s t a n t across t r e a t m e n t s . Specific gravity of t h e salt-brine was held c o n s t a n t t h r o u g h o u t t h e chilling period (1.035 ± . 0 0 5 ) . Prior t o packaging in Cry-O-Vac bags, t h e chilled carcasses were rinsed, allowed to drain for 15 m i n and reweighed (post-chill w t ) . All birds were t h e n frozen and held at —18 C. After thawing ( 4 8 hr a t 4 C), carcasses were weighed (post-
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ABSTRACT Percent water uptake, thawing, and cooking losses were determined on broiler carcasses which had been ice-slush chilled (ice slush, 1 C overnight), brine chilled (5% NaCl, —1 C overnight), and hot packaged (no chill). After cooking, the meat samples were evaluated for flavor, tenderness, and juiciness by a taste panel. Shear force and percent moisture analyses were also conducted. Carcasses and chill water were tested for microbial population throughout the experiment. Brine-chilled carcasses had significantly greater water uptake and lower thawing and cooking losses than conventionally-chilled carcasses. While all samples were scored favorably for flavor, tenderness, and juiciness, brine-chilled samples received higher scores than conventionally-chilled or hot-packaged samples. Meat from brine-chilled carcasses had a significantly higher moisture content and lower shear force values (more tender) than meat from conventionally-chilled or hot-packaged carcasses. Total plate and coliform counts were lower for both brine-chilled and conventionallychilled carcasses than for hot-packaged carcasses. Adding salt to the chill water slightly decreased the microbial population in the chill water during chilling.
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D. M. JANKY, A. S. ARAFA, J. L. OBLINGER, J. A. KOBURGER AND D. L. FLETCHER phosphate buffer. Serial dilutions of the wash water were plated in duplicate with Plate Count Agar (Difco) and incubated at 35 C and 20 C for total aerobes. Coliforms and fecal coliforms were enumerated using a 3-tube Most Probable Number (MPN) procedure of Lauryl Sulfate Tryptose Broth (Difco) followed by confirmation in Brilliant Green Lactose Bile 2% Broth (Difco) incubated at 35 C for total coliforms and EC Broth (Difco) incubated at 45.5 C for fecal coliforms. Data were subjected to analyses of variance and Duncan's multiple range test in order to determine the significance of treatment means (Steel and Torrie, 1960). Three trials of the entire experiment were conducted (a total of 135 birds) and, since there were no significant trial X treatment interactions, the data from all three trials were pooled. RESULTS AND DISCUSSION Taste panel scores for flavor, tenderness, and juiciness of meat from brine-chilled carcasses were significantly higher than those scores for meat from water-chilled or hot-packaged carcasses (Table 1). The panelists were not able to distinguish any difference in meat from carcasses treated with the latter two methods. All scores were in the acceptable range. Although not statistically analyzed, the preference of the panelists was obviously the meat from brinechilled carcasses over that obtained from water-chilled or hot-packaged carcasses. This may have been associated with the added salt due to the brine chilling. The force required to shear a gram of meat from brine-chilled carcasses was significantly
TABLE 1 .—Taste panel scores^ for meat (average of light and dark) from broiler carcasses which were either hot packaged (no chill), water-ice slush immersion chilled or brine-ice slush immersion chilled" Evaluation
Treatment
Flavor
Tenderness
Hot packed Water-ice slush immersion Brine-ice slush immersion
3.0 a 2.9 a 4.0 b
3.3 a 3.2 a 4.0b
Juiciness 2.9 a 2.9 a 3.8 b
Preference
(%) 11.4 10.1 78.5
Scoring system: 1) very unacceptable, tough or dry; 2) moderately unacceptable, tough or dry; 3) acceptable, tender or moist;4) more acceptable, tender or moist;and 5) very acceptable, tender or moist. Means within a column having different superscripts are significantly different (P<.05).
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thaw wt) and cooked to an internal temperature of 85 C (thermocouple at thigh-abdomen junction) in a conventional electric oven at 180 C. All birds were covered with aluminum foil during cooking. Following a half-hour cooling period, the cooked carcasses were weighed (post-cook wt) and held overnight at 1 C. Bite sized samples of the pectoralis muscles (light) and the biceps femoris, ilio tibialis muscles (dark) cut from the cold carcasses were evaluated by an experienced taste panel (10 persons/meat type) for flavor, juiciness, and tenderness on a 5 point scale (Table 1). Each panelist tasted either light or dark meat from all treatments and was asked to state a preference for a particular sample from the group of three samples tasted. Samples of the pectoralis major (20 X 40 X 3 mm.) and biceps femoris (15 X 30 X 2 mm.) were analyzed for shear force using a Food Technology Corporation Texture Test System® according to the procedure described by Oblinger et al. (1976). The percent moisture of cooked pectoralis muscles (light meat) and thigh muscles (dark meat) was determined using the standard method (AOAC, 1970). Percent carcass water pick-up, thaw loss, cooking loss, cooked yield (post-chill), and cooked yield (pre-chill) were calculated using the formulae shown in Table 4. Carcasses were analyzed for total aerobes and coliforms before (control) and after chilling (16 hr) and hot-packaging. Also, analyses were carried out on cooked carcasses. The brine and chill water were analyzed prior to the addition of birds and at 16 hr after the birds were added Sampling of the birds was accomplished by rinsing each whole bird with 100 ml of sterile
SALT-BRINE CHILLING OF BROILERS
419
TABLE 2.—Shear force values for light and dark meat from broiler carcasses which were either hot packaged (no chill), waterice slush immersion chilled or brine-ice slush immersion chilled^Meat type Light
Treatment
Dark
Combined^'^-
(kg force/g of sample) C
Hot pack Water-ice slush immersion Brine-ice slush immersion
6.1 5.5C 2.6 a
4.9DC
3.3 a 3.4-ab
5.5 Z 4.4Y 3.OX
Means having different superscripts (a through c) are significantly different (P<.05). BAverage value for light and dark meat. "Means having different superscripts (x through z) are significantly different (P<.05).
Percent
moisture
of
cooked
meat
from
TABLE 3.—Moisture content of cooked meat (average of light and dark) from broiler carcasses which were either hot packaged (no chill), water-ice slush immersion chilled or brine-slush immersion chilled^
Treatment
% moisture
Hot pack Water-ice slush immersion Brine-ice slush immersion
67.78 a 68.50 a 70.41 b
Means with different superscripts are significantly different (P<.05).
brine-chilled carcasses was significantly higher t h a n for m e a t from water-chilled or hot-packaged carcasses (Table 3). There was n o a p p a r e n t difference in percent moisture of c o o k e d m e a t from water-chilled or hot-packaged carcasses. These results were similar t o t h e juiciness scores o b t a i n e d with t h e taste panel. This might also explain t h e observed tenderization effect of brine chilling in t h a t it has been observed t h a t t h e greater t h e a m o u n t of m o i s t u r e retained after cooking, t h e more tender t h e p r o d u c t (Essary et al., 1 9 6 8 ) . T h e percentage of water picked u p by t h e carcasses during t h e chilling period was significantly higher with t h e brine-chilling p r o c e d u r e t h a n with t h e conventional water-chilling procedure (Table 4 ) . T h e percent t h a w loss, however, from brine-chilled carcasses was significantly lower than t h a t obtained with slush-ice-chilled carcasses. T h e brine-chilled carcasses did n o t differ in t h a w loss from t h e hot-packaged carcasses (no-chill). Since t h e hot-packaged carcasses were n o t immersion chilled and did n o t pick u p any extra moisture, it was e x p e c t e d t h a t these carcasses would have had minimal t h a w loss. It is interesting, however, t h a t t h e brine-chilled carcasses had as low a thawing loss as hot-packaged carcasses even t h o u g h t h e brine-chilled carcasses picked up significantly m o r e water than the ice-slush immersion chilled carcasses. Percent cooking loss of slush-icechilled carcasses was significantly higher than t h a t of brine-chilled or hot-packaged carcasses (Table 4 ) . T h e overall cooked yield of t h e slush-ice-chilled carcasses, based o n t h e postchill wt (ready-to-cook), was significantly lower t h a t t h a t observed for either brine-chilled or
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less than t h a t required t o shear m e a t from water-chilled or hot-packaged carcasses (Table 2). Meat from hot-packaged carcasses had significantly higher shear values t h a n did m e a t from water-chilled carcasses. These results were consistent with t h e panelists' scores for tenderness e x c e p t t h a t t h e panelists were n o t able to differentiate b e t w e e n meat from water-chilled and hot-packaged carcasses. There was a significant interaction b e t w e e n chilling p r o c e d u r e and m e a t t y p e in t h a t light m e a t from brine-chilled carcasses had lower shear values than dark meat (Table 2). For t h e o t h e r t w o t r e a t m e n t s , light m e a t had higher shear values than dark m e a t . It appeared t h a t light meat was affected to a greater e x t e n t by t h e brine chilling than was dark meat. Previous work with brining of ready-to-cook Cornish hens and broilers also resulted in a greater effect on shear values of light meat ( J a n k y et al., 1976, Oblinger et al, 1976).
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D. M. JANKY, A. S. ARAFA, J. L. OBLINGER, J. A. KOBURGER AND D. L. FLETCHER TABLE 4.— Yield characteristics of broiler carcasses which were either hot packaged (no chill), water-ice slush immersion chilled or brine-ice slush immersion chilled^-
Water pick u p B
Thaw loss*-
Cook loss"-*
Cooked
Treatment
(%)
(%)
(%)
(%)
Cooked yieldF from pre-chill wt (%)
H o t pack Water-ice slush immersion Brine-ice slush immersion
5.09a 6.34b
1.41a 4.42b 1.98a
20.92a 23.67b 20.0 7 a
77.97a 72.95b 78.34a
77.97a 76.67a 83.30b
yield E
Means within a column having different superscripts are significantly different (P<.05). B
(Post-chill wt - pre-chill wt X 100)/(pre-chill wt).
^(Post-cook wt X 100)/(post-chill wt). F (Post-cook wt X 100)/(pre-chill wt).
hot-packaged carcasses. If the cooked yield was calculated based on the pre-chill weight of the carcass, the brine-chilled carcasses had a significantly higher percent yield than either the slush-ice-chilled or hot-packaged carcasses (Table 4). These data indicated that the salt-brine chilling procedure increased the water holding capacity of the muscle tissue. Thus, more tender, juicier meat would result along with less drip and higher cooked yield. Comparable levels of total aerobes, coliforms, and fecal coliforms were found in both the chill water or brine soon after the addition
of the carcasses (Table 5). When birds were sampled after 16 hr, there was approximately a one log cycle reduction in numbers of aerobes and coliforms on the brine-chilled birds when compared to either hot-packaged or waterchilled birds. *s expected, conventional ovenroasting of bn^s, regardless of pre-cooking treatment, resulted in very low numbers of aerobes present after cooking and no coliform or fecal coliform survivors. It is presumed that the low number of aerobes encountered after cooking represented post-processing contamination rather than cooking survival.
TABLE 5.—Microbial populations^- of various aspects of the chilling process Microbial d e t e r m i n a t i o n s Sample
APC: (35C)B
APC (20 C ) c
Coliforms'-'
Fecal coliforms^
Chill w a t e r (w/o birds) Chill w a t e r (w/birds after 16 hr) Brine (w/o birds) Brine (w/birds after 16 hr)
2.0 3.3 5.8 2.3
X X X X
10' 103 102 103
1.5 3.5 4.3 2.0
X X X X
10' 103 10 2 103
<10 4.3 X 10 2 <10 1.3 X 10 2
<10 6.7 X 1 0 ' <10 2.9 X 1 0 '
Control birds Water-soaked birds (16 hr) Brined birds (16 hr) Hot-packed birds Cooked birds
6.5 1.7 4.4 1.8 6.6
X X X X X
10" 10 4 103 10s 10'
5.6 1.3 4.8 1.5 6.3
X X X X X
10" 10 4 103 10 4 10'
7.5 X 1.4 X 2.9 X 2.0 X <10
10 4 103 10 2 103
A.,
Each figure represents the mean of at least three (3) duplicate determinations.
APC — aerobic plate count/ml chill water or per ml rinse culture. Coliforms — total coliform most probable number (MPN)/ml chill water or per ml rinse culture. Fecal coliforms — MPN/ml chill water or per ml rinse culture.
2.2 X 2.5 X 8.9 X 5.2 X <10
10" 10 2 10' 10 2
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"(Post-chill wt — post-thaw wt X 100)/(post-chill wt). D(Post-thaw wt — post-cook wt X 100)/(post-thaw wt).
SALT-BRINE CHILLING OF BROILERS REFERENCES A.O.A.C. Official methods of analyses, 1970. 10th ed. Association of Official Agricultural Chemists, Washington, DC. Arafa, A. S., 1975. Microbiological, biophysical and organoleptic characteristics of poultry meat as related to postmortem treatments. Ph.D. dissertation, Mississippi State University, Starkville, MS. Brotsky, E., 1976. Automatic injection of chicken parts with polyphosphate. Poultry Sci. 55:653 — 660. Essary, E. O., I. M. Norris, G. A. Schuler and S. P. Singh, 1968. Influence of cooking broiler meat in water on tenderness and percentage moisture. Poultry Sci. 47:1949-1953. Gardner, F. A., and R. L. Atkinson, 1967. Tissue changes associated with chilling broilers in sodium chloride solutions. Poultry Sci. 46:1262.
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Janky, D. M., J. A. Koburger, J. L. Oblinger and P. K. Riley, 1976. Effect of salt brining and cooking procedure on tenderness and microbiology of s m o k e d Cornish game hens. Poultry Sci. 55:761-764. Klose, A. A., A. A. Campbell and H. L. Hanson, 1963. Influence of polyphosphates in chilling water on quality of poultry meat. Poultry Sci. 43:743—749. Oblinger, J. L., D. M. Janky and J. A. Koburger, 1976. The effect of water soaking, brining and cooking procedure on tenderness of broilers. Poultry Sci. 55:1494-1497. Shults, G. W., and E. Wierbicki, 1973. Effects of sodium chloride and condensed phosphates on the water-holding capacity, pH and swelling of chicken muscle. J. Food Sci. 38:991-994. Steel, G. O., and J. H. Torrie, 1960. Principles and procedures of statistics. McGraw-Hill Book Co., New York, NY. Downloaded from http://ps.oxfordjournals.org/ at NERL on May 14, 2015
INTRODUCTION Arafa ( 1 9 7 5 ) r e p o r t e d t h a t hot-packaging of p o u l t r y greatly reduced drip formation a n d increased shelf-life when c o m p a r e d with slushice-chilled p o u l t r y . This a u t h o r also observed higher cooking yield and b e t t e r flavor scores for hot-packaged birds. T h e a c t i o n of salts, such as p o l y p h o s p h a t e s , on t h e water holding capacity of p o u l t r y m e a t is well d o c u m e n t e d (Klose et ai, 1 9 6 3 , Brotsky, 1976). Treating chicken muscle with NaCl in c o m b i n a t i o n with p o l y p h o s p h a t e s has been observed t o increase water holding capacity and decrease shrink (Shults and Wierbicki, 1 9 7 3 ) . T h e immersion of ready-to-cook broilers in NaCl solutions prior t o smoking has been shown to increase t h e tenderness of t h e m e a t from these birds (Oblinger et ai, 1 9 7 6 ) . These a u t h o r s further observed a slight toughening effect w h e n carcasses were immersed in water for similar t i m e s before smoking. G a r d n e r and Atkinson ( 1 9 6 7 ) chilled broiler carcasses in varying solutions of NaCl and observed little
1
Florida Agr. Exp. Stas. Journal Series No. 613. Department of Poultry Science, University of Florida, Gainesville, Florida 32611. 3 Department of Food Science, University of Florida, Gainesville, Florida 32611. 2
1978 Poultry Sci 57:417-421
effect on the physical characteristics of t h e carcasses. In view of these findings, it was theorized t h a t salt-brine chilling as a processing t e c h n i q u e might influence p o u l t r y m e a t tenderness and quality. T h e purpose of this e x p e r i m e n t was t o c o m p a r e various physical, sensory, and microbiological characteristics of brine-chilled, slushice-chilled (control), and hot-packaged (negative control with n o chill) carcasses. EXPERIMENTAL PROCEDURE Forty-five male C o b b color-sexed broilers 8 weeks-of age were slaughtered b y exsanguination, subscalded (60 C for 45 sec), and picked in a r o t a r y d r u m picker. After evisceration t h e carcasses were rinsed and weighed (pre-chill) and assigned t o one of the following three chilling procedures: hot-packaged (no chill), overnight chilling in ice slush (1 C), or overnight chilling in a 5% NaCl ice slush (—1 C). T h e ratio of chill water volume t o bird w t was k e p t c o n s t a n t across t r e a t m e n t s . Specific gravity of t h e salt-brine was held c o n s t a n t t h r o u g h o u t t h e chilling period (1.035 ± . 0 0 5 ) . Prior t o packaging in Cry-O-Vac bags, t h e chilled carcasses were rinsed, allowed to drain for 15 m i n and reweighed (post-chill w t ) . All birds were t h e n frozen and held at —18 C. After thawing ( 4 8 hr a t 4 C), carcasses were weighed (post-
417
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ABSTRACT Percent water uptake, thawing, and cooking losses were determined on broiler carcasses which had been ice-slush chilled (ice slush, 1 C overnight), brine chilled (5% NaCl, —1 C overnight), and hot packaged (no chill). After cooking, the meat samples were evaluated for flavor, tenderness, and juiciness by a taste panel. Shear force and percent moisture analyses were also conducted. Carcasses and chill water were tested for microbial population throughout the experiment. Brine-chilled carcasses had significantly greater water uptake and lower thawing and cooking losses than conventionally-chilled carcasses. While all samples were scored favorably for flavor, tenderness, and juiciness, brine-chilled samples received higher scores than conventionally-chilled or hot-packaged samples. Meat from brine-chilled carcasses had a significantly higher moisture content and lower shear force values (more tender) than meat from conventionally-chilled or hot-packaged carcasses. Total plate and coliform counts were lower for both brine-chilled and conventionallychilled carcasses than for hot-packaged carcasses. Adding salt to the chill water slightly decreased the microbial population in the chill water during chilling.
418
D. M. JANKY, A. S. ARAFA, J. L. OBLINGER, J. A. KOBURGER AND D. L. FLETCHER phosphate buffer. Serial dilutions of the wash water were plated in duplicate with Plate Count Agar (Difco) and incubated at 35 C and 20 C for total aerobes. Coliforms and fecal coliforms were enumerated using a 3-tube Most Probable Number (MPN) procedure of Lauryl Sulfate Tryptose Broth (Difco) followed by confirmation in Brilliant Green Lactose Bile 2% Broth (Difco) incubated at 35 C for total coliforms and EC Broth (Difco) incubated at 45.5 C for fecal coliforms. Data were subjected to analyses of variance and Duncan's multiple range test in order to determine the significance of treatment means (Steel and Torrie, 1960). Three trials of the entire experiment were conducted (a total of 135 birds) and, since there were no significant trial X treatment interactions, the data from all three trials were pooled. RESULTS AND DISCUSSION Taste panel scores for flavor, tenderness, and juiciness of meat from brine-chilled carcasses were significantly higher than those scores for meat from water-chilled or hot-packaged carcasses (Table 1). The panelists were not able to distinguish any difference in meat from carcasses treated with the latter two methods. All scores were in the acceptable range. Although not statistically analyzed, the preference of the panelists was obviously the meat from brinechilled carcasses over that obtained from water-chilled or hot-packaged carcasses. This may have been associated with the added salt due to the brine chilling. The force required to shear a gram of meat from brine-chilled carcasses was significantly
TABLE 1 .—Taste panel scores^ for meat (average of light and dark) from broiler carcasses which were either hot packaged (no chill), water-ice slush immersion chilled or brine-ice slush immersion chilled" Evaluation
Treatment
Flavor
Tenderness
Hot packed Water-ice slush immersion Brine-ice slush immersion
3.0 a 2.9 a 4.0 b
3.3 a 3.2 a 4.0b
Juiciness 2.9 a 2.9 a 3.8 b
Preference
(%) 11.4 10.1 78.5
Scoring system: 1) very unacceptable, tough or dry; 2) moderately unacceptable, tough or dry; 3) acceptable, tender or moist;4) more acceptable, tender or moist;and 5) very acceptable, tender or moist. Means within a column having different superscripts are significantly different (P<.05).
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thaw wt) and cooked to an internal temperature of 85 C (thermocouple at thigh-abdomen junction) in a conventional electric oven at 180 C. All birds were covered with aluminum foil during cooking. Following a half-hour cooling period, the cooked carcasses were weighed (post-cook wt) and held overnight at 1 C. Bite sized samples of the pectoralis muscles (light) and the biceps femoris, ilio tibialis muscles (dark) cut from the cold carcasses were evaluated by an experienced taste panel (10 persons/meat type) for flavor, juiciness, and tenderness on a 5 point scale (Table 1). Each panelist tasted either light or dark meat from all treatments and was asked to state a preference for a particular sample from the group of three samples tasted. Samples of the pectoralis major (20 X 40 X 3 mm.) and biceps femoris (15 X 30 X 2 mm.) were analyzed for shear force using a Food Technology Corporation Texture Test System® according to the procedure described by Oblinger et al. (1976). The percent moisture of cooked pectoralis muscles (light meat) and thigh muscles (dark meat) was determined using the standard method (AOAC, 1970). Percent carcass water pick-up, thaw loss, cooking loss, cooked yield (post-chill), and cooked yield (pre-chill) were calculated using the formulae shown in Table 4. Carcasses were analyzed for total aerobes and coliforms before (control) and after chilling (16 hr) and hot-packaging. Also, analyses were carried out on cooked carcasses. The brine and chill water were analyzed prior to the addition of birds and at 16 hr after the birds were added Sampling of the birds was accomplished by rinsing each whole bird with 100 ml of sterile
SALT-BRINE CHILLING OF BROILERS
419
TABLE 2.—Shear force values for light and dark meat from broiler carcasses which were either hot packaged (no chill), waterice slush immersion chilled or brine-ice slush immersion chilled^Meat type Light
Treatment
Dark
Combined^'^-
(kg force/g of sample) C
Hot pack Water-ice slush immersion Brine-ice slush immersion
6.1 5.5C 2.6 a
4.9DC
3.3 a 3.4-ab
5.5 Z 4.4Y 3.OX
Means having different superscripts (a through c) are significantly different (P<.05). BAverage value for light and dark meat. "Means having different superscripts (x through z) are significantly different (P<.05).
Percent
moisture
of
cooked
meat
from
TABLE 3.—Moisture content of cooked meat (average of light and dark) from broiler carcasses which were either hot packaged (no chill), water-ice slush immersion chilled or brine-slush immersion chilled^
Treatment
% moisture
Hot pack Water-ice slush immersion Brine-ice slush immersion
67.78 a 68.50 a 70.41 b
Means with different superscripts are significantly different (P<.05).
brine-chilled carcasses was significantly higher t h a n for m e a t from water-chilled or hot-packaged carcasses (Table 3). There was n o a p p a r e n t difference in percent moisture of c o o k e d m e a t from water-chilled or hot-packaged carcasses. These results were similar t o t h e juiciness scores o b t a i n e d with t h e taste panel. This might also explain t h e observed tenderization effect of brine chilling in t h a t it has been observed t h a t t h e greater t h e a m o u n t of m o i s t u r e retained after cooking, t h e more tender t h e p r o d u c t (Essary et al., 1 9 6 8 ) . T h e percentage of water picked u p by t h e carcasses during t h e chilling period was significantly higher with t h e brine-chilling p r o c e d u r e t h a n with t h e conventional water-chilling procedure (Table 4 ) . T h e percent t h a w loss, however, from brine-chilled carcasses was significantly lower than t h a t obtained with slush-ice-chilled carcasses. T h e brine-chilled carcasses did n o t differ in t h a w loss from t h e hot-packaged carcasses (no-chill). Since t h e hot-packaged carcasses were n o t immersion chilled and did n o t pick u p any extra moisture, it was e x p e c t e d t h a t these carcasses would have had minimal t h a w loss. It is interesting, however, t h a t t h e brine-chilled carcasses had as low a thawing loss as hot-packaged carcasses even t h o u g h t h e brine-chilled carcasses picked up significantly m o r e water than the ice-slush immersion chilled carcasses. Percent cooking loss of slush-icechilled carcasses was significantly higher than t h a t of brine-chilled or hot-packaged carcasses (Table 4 ) . T h e overall cooked yield of t h e slush-ice-chilled carcasses, based o n t h e postchill wt (ready-to-cook), was significantly lower t h a t t h a t observed for either brine-chilled or
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less than t h a t required t o shear m e a t from water-chilled or hot-packaged carcasses (Table 2). Meat from hot-packaged carcasses had significantly higher shear values t h a n did m e a t from water-chilled carcasses. These results were consistent with t h e panelists' scores for tenderness e x c e p t t h a t t h e panelists were n o t able to differentiate b e t w e e n meat from water-chilled and hot-packaged carcasses. There was a significant interaction b e t w e e n chilling p r o c e d u r e and m e a t t y p e in t h a t light m e a t from brine-chilled carcasses had lower shear values than dark meat (Table 2). For t h e o t h e r t w o t r e a t m e n t s , light m e a t had higher shear values than dark m e a t . It appeared t h a t light meat was affected to a greater e x t e n t by t h e brine chilling than was dark meat. Previous work with brining of ready-to-cook Cornish hens and broilers also resulted in a greater effect on shear values of light meat ( J a n k y et al., 1976, Oblinger et al, 1976).
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D. M. JANKY, A. S. ARAFA, J. L. OBLINGER, J. A. KOBURGER AND D. L. FLETCHER TABLE 4.— Yield characteristics of broiler carcasses which were either hot packaged (no chill), water-ice slush immersion chilled or brine-ice slush immersion chilled^-
Water pick u p B
Thaw loss*-
Cook loss"-*
Cooked
Treatment
(%)
(%)
(%)
(%)
Cooked yieldF from pre-chill wt (%)
H o t pack Water-ice slush immersion Brine-ice slush immersion
5.09a 6.34b
1.41a 4.42b 1.98a
20.92a 23.67b 20.0 7 a
77.97a 72.95b 78.34a
77.97a 76.67a 83.30b
yield E
Means within a column having different superscripts are significantly different (P<.05). B
(Post-chill wt - pre-chill wt X 100)/(pre-chill wt).
^(Post-cook wt X 100)/(post-chill wt). F (Post-cook wt X 100)/(pre-chill wt).
hot-packaged carcasses. If the cooked yield was calculated based on the pre-chill weight of the carcass, the brine-chilled carcasses had a significantly higher percent yield than either the slush-ice-chilled or hot-packaged carcasses (Table 4). These data indicated that the salt-brine chilling procedure increased the water holding capacity of the muscle tissue. Thus, more tender, juicier meat would result along with less drip and higher cooked yield. Comparable levels of total aerobes, coliforms, and fecal coliforms were found in both the chill water or brine soon after the addition
of the carcasses (Table 5). When birds were sampled after 16 hr, there was approximately a one log cycle reduction in numbers of aerobes and coliforms on the brine-chilled birds when compared to either hot-packaged or waterchilled birds. *s expected, conventional ovenroasting of bn^s, regardless of pre-cooking treatment, resulted in very low numbers of aerobes present after cooking and no coliform or fecal coliform survivors. It is presumed that the low number of aerobes encountered after cooking represented post-processing contamination rather than cooking survival.
TABLE 5.—Microbial populations^- of various aspects of the chilling process Microbial d e t e r m i n a t i o n s Sample
APC: (35C)B
APC (20 C ) c
Coliforms'-'
Fecal coliforms^
Chill w a t e r (w/o birds) Chill w a t e r (w/birds after 16 hr) Brine (w/o birds) Brine (w/birds after 16 hr)
2.0 3.3 5.8 2.3
X X X X
10' 103 102 103
1.5 3.5 4.3 2.0
X X X X
10' 103 10 2 103
<10 4.3 X 10 2 <10 1.3 X 10 2
<10 6.7 X 1 0 ' <10 2.9 X 1 0 '
Control birds Water-soaked birds (16 hr) Brined birds (16 hr) Hot-packed birds Cooked birds
6.5 1.7 4.4 1.8 6.6
X X X X X
10" 10 4 103 10s 10'
5.6 1.3 4.8 1.5 6.3
X X X X X
10" 10 4 103 10 4 10'
7.5 X 1.4 X 2.9 X 2.0 X <10
10 4 103 10 2 103
A.,
Each figure represents the mean of at least three (3) duplicate determinations.
APC — aerobic plate count/ml chill water or per ml rinse culture. Coliforms — total coliform most probable number (MPN)/ml chill water or per ml rinse culture. Fecal coliforms — MPN/ml chill water or per ml rinse culture.
2.2 X 2.5 X 8.9 X 5.2 X <10
10" 10 2 10' 10 2
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"(Post-chill wt — post-thaw wt X 100)/(post-chill wt). D(Post-thaw wt — post-cook wt X 100)/(post-thaw wt).
SALT-BRINE CHILLING OF BROILERS REFERENCES A.O.A.C. Official methods of analyses, 1970. 10th ed. Association of Official Agricultural Chemists, Washington, DC. Arafa, A. S., 1975. Microbiological, biophysical and organoleptic characteristics of poultry meat as related to postmortem treatments. Ph.D. dissertation, Mississippi State University, Starkville, MS. Brotsky, E., 1976. Automatic injection of chicken parts with polyphosphate. Poultry Sci. 55:653 — 660. Essary, E. O., I. M. Norris, G. A. Schuler and S. P. Singh, 1968. Influence of cooking broiler meat in water on tenderness and percentage moisture. Poultry Sci. 47:1949-1953. Gardner, F. A., and R. L. Atkinson, 1967. Tissue changes associated with chilling broilers in sodium chloride solutions. Poultry Sci. 46:1262.
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Janky, D. M., J. A. Koburger, J. L. Oblinger and P. K. Riley, 1976. Effect of salt brining and cooking procedure on tenderness and microbiology of s m o k e d Cornish game hens. Poultry Sci. 55:761-764. Klose, A. A., A. A. Campbell and H. L. Hanson, 1963. Influence of polyphosphates in chilling water on quality of poultry meat. Poultry Sci. 43:743—749. Oblinger, J. L., D. M. Janky and J. A. Koburger, 1976. The effect of water soaking, brining and cooking procedure on tenderness of broilers. Poultry Sci. 55:1494-1497. Shults, G. W., and E. Wierbicki, 1973. Effects of sodium chloride and condensed phosphates on the water-holding capacity, pH and swelling of chicken muscle. J. Food Sci. 38:991-994. Steel, G. O., and J. H. Torrie, 1960. Principles and procedures of statistics. McGraw-Hill Book Co., New York, NY. Downloaded from http://ps.oxfordjournals.org/ at NERL on May 14, 2015