H Zhuang

United States Department of Agriculture, Washington, D. C., DC, United States

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Publications (11)13.9 Total impact

  • H Zhuang, E M Savage
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    ABSTRACT: Four replications were conducted to compare sensory descriptive profiles of cooked boneless skinless chicken breast categorized by fillet (pectoralis major) weight or size. In each replication, 20 heavy fillets, 20 medium fillets, and 20 light fillets (deboned at 6-8 h postmortem) were obtained from a commercial processing plant. Fillets were trimmed and weighed before chosen for each of 3 size categories based on their weight as follows: light, average weight 112 g; medium, average weight 153 g; and heavy, average weight 204 g. Descriptive sensory texture and flavor attributes were measured after the frozen samples were thawed for 24 h at a refrigerated temperature (2°C) and cooked to an endpoint temperature of 78°C. Sensory evaluations were performed by trained descriptive panelists using 0 to 15 universal intensity scales for 8 texture and 10 flavor attributes. Our results show that there were differences (P < 0.05) in intensity scores of sensory descriptive texture and flavor attributes cohesiveness, hardness, juiciness, cardboardy, and sourness, among the 3 weight categories. The average cohesiveness, hardness, and sourness scores of the heavy and light fillets were higher than the medium fillets. The juiciness score of the heavy fillets was higher than that of the light fillets, and the cardboardy score of the light fillets was higher than those of the medium and heavy fillets. The juiciness score of the medium fillets did not differ from that of either the light or heavy fillets, and there was no difference for cardboardy scores between the medium and heavy fillets. These results indicate that fillet weight or size in the range (95-230 g) assessed in this study may influence sensory descriptive flavor and texture profiles of cooked broiler breast fillets deboned 6 to 8 h postmortem. Current genetic selection of broiler lines based on growth rate and feed efficiency may sacrifice breast meat quality. However, it remains to be determined if the differences in the sensory descriptive evaluation can be perceived by consumers.
    Poultry Science 07/2012; 91(7):1695-702. · 1.52 Impact Factor
  • H Zhuang, E M Savage
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    ABSTRACT: The effects of postdeboning aging and frozen storage on water-holding capacity (WHC) of chicken breast pectoralis major muscle were investigated. Broiler breast muscle was removed from carcasses either early postmortem (2 h) or later postmortem (24 h). Treatments included: no postdeboning aging; 1-d postdeboning aging at 2°C, 7-d postdeboning aging (2-h deboned meat only), and 6-d storage at -20°C plus 1-d thawing at 2°C (freezing and thawing treatment, 2-h deboned meat only). The WHC was determined by cooking loss, drip loss, a filter paper press method (results were presented as expressible fluid), and a salt-induced swelling and centrifugation method (results were presented as percentage of salt-induced water gain). There were no differences for WHC estimated by cooking loss and expressible fluid between the treatments. Only the freezing and thawing treatment resulted in a significant increase in drip loss. The average percentage of salt-induced water gains by the 24-h deboned samples, postdeboning aged 2 h samples, and frozen 2 h sample, which did not differ from each other, were significantly higher than that by the 2-h deboned sample. These results indicate that regardless of method (carcass aging vs. postdeboning aging) and time (aging for 1 d vs. for 7 d), postmortem aging more than 1 d does not affect WHC of the early deboned samples measured by dripping, cooking, and pressing. However, postmortem carcass aging, postdeboning aging, and freezing and thawing storage can significantly enhance the ability of chicken breast meat to hold added salt water or WHC measured by the salt-induced swelling and centrifuge method.
    Poultry Science 05/2012; 91(5):1203-9. · 1.52 Impact Factor
  • Hong Zhuang, Elizabeth M. Savage
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    ABSTRACT: Three trials were conducted to investigate the effect of deboning times postmortem on sensory descriptive flavor and texture profiles of cooked boneless skinless chicken thigh muscles (iliotibialis, iliofibularis and the femoritibialis). Broiler carcasses (42-d old birds) were procured from a commercial processing plant. Thighs were hot-boned (about 45 min postmortem), cold-deboned 2 h (2 h) or 24 h (24 h) postmortem. Sensory descriptive tests were performed on cooked meat by 8 trained descriptive panelists using 0–15 universal intensity scale. Our results show that there were no significant differences in average intensity scores of the tested texture and flavor attributes between the hot-boned and 2 h thigh meat. No significant differences for the sensory flavor attributes were found due to three deboning times. However, the intensity scores of 24 h thighs were significantly lower than the hot-boned and 2 h thighs (p
    Lwt - Food Science and Technology. 01/2011; 44(10):2087-2090.
  • H Zhuang, E M Savage, K Lawrence
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    ABSTRACT: The present experiment was carried out to evaluate the effects of electrical stimulation (ES) immediately prescalding (PS), ES immediately postdefeathering (PD), or PS combined with PD (PSPD) on the quality of early deboned (2 h) broiler breast muscles, pectoralis major (fillets), and pectoralis minor (tenders). No stimulation, early-deboned (2 h), and 24-h deboned (24 h) fillets were used for the comparison. The 42-d-old broiler carcasses were electrically stimulated with pulsed current at 200 V for 30 s over a 90-s time interval (total of 1 min over 180 s for PSPD), and breast meat was deboned 2 h postmortem. Quality indicators evaluated were CIE L*, a*, and b* color and pH of the raw fillets and cook yields and Warner-Bratzler (WB) shear force of the fillets and tenders. There were no differences in raw fillet color, pH, and cook yields of both the fillets and tenders between the 3 ES treatments. Effects of different ES treatments on meat WB shear force values varied with breast muscles. For the fillets, the average WB shear force values of both the PS and PSPD samples, which were not different from each other, were significantly lower than those of the PD samples. For the tenders, there were no differences in the average shear force values between the 3 ES treatments. Regardless of ES treatment and breast muscle, early deboned broiler breast meat from ES carcasses required significantly less force to shear than the 2-h control. These results indicate that ES can tenderize early deboned poultry breast muscles; however, the effectiveness of ES tenderization varies with ES treatments for the fillets. The PS treatment is more effective in reducing fillet shear values than PD, and there is no further reduction in shear values with PSPD compared with the PS treatment.
    Poultry Science 08/2010; 89(8):1737-43. · 1.52 Impact Factor
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    H Zhuang, E M Savage
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    ABSTRACT: Three replicate trials were conducted to compare sensory descriptive profiles of cooked broiler breast fillets categorized by raw meat color lightness or CIE L* values. In each trial, 20 light, 20 dark, and 30 random fillets (42-d-old birds and deboned at 6 to 8 h postmortem) were obtained from a commercial processing plant. On return to the laboratory, CIE L* a* b* (medial side), pH, and weights were measured. Ten fillets for each of 3 lightness categories were chosen based on the L* values as follows: light, L* > 60; medium (middle of random group), 55 < L* < 59; and, dark, L* < 55. Cook yield, Warner-Bratzler shear force, and descriptive sensory attributes were measured on the chosen fillets after 7 d of frozen storage followed by cooking to an endpoint temperature of 78 to 80 degrees C. Sensory evaluations were performed by trained descriptive panelists using universal intensity scales of 0 to 15 for 9 flavor and 8 texture attributes. Our results show that there were significant differences among the 3 lightness categories for pH, thaw loss, cook yield, and shear force. There were no significant differences in average flavor intensity scores between the 3 lightness categories. However, the average intensity scores of the texture attributes cohesiveness, hardness, rate of breakdown, and chewiness of the light fillets were significantly higher than either the dark or the medium fillets (P < 0.01), which did not differ from each other. These results indicate that sensory flavor profiles of cooked broiler breast fillets are similar regardless of raw meat color lightness (or L* values). There is no difference in the texture profiles between the cooked medium and dark fillets. But the sensory texture profile of fillets categorized as light based on CIE L* values is different from those of the fillets categorized as either medium or dark.
    Poultry Science 05/2010; 89(5):1049-55. · 1.52 Impact Factor
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    ABSTRACT: The objective of this study was to evaluate the effect of a dry air-chilling (AC) method on sensory texture and flavor descriptive profiles of broiler pectoralis major (fillet) and pectoralis minor (tender). The profiles of the muscles immersion-chilled and deboned at the same postmortem time and the profiles of the muscles hot-boned (or no chill) were used for the comparison. A total of 108 eviscerated carcasses (6-wk-old broilers) were obtained from a commercial processing line before the chillers. Carcasses were transported to a laboratory facility where they were either i) chilled by a dry AC method (0.7 degrees C, 150 min in a cold room), ii) chilled by immersion chilling (IC; 0.3 degrees C, 50 min in a chiller), or iii) not chilled (9 birds per treatment per replication). Both IC and AC fillets and tenders were removed from the bone at 4 h after the initiation of chilling (approximately 4.75 h postmortem) in a processing area (18 degrees C). The no-chill muscles were removed immediately upon arrival. The sensory properties (21 attributes) of cooked broiler breast meat were evaluated by trained panelists using 0- to 15-point universal intensity scales. The average intensity scores of the 9 flavor attributes analyzed ranged from 0.9 to 4.0. Regardless of breast muscle type, there were no significant differences in sensory flavor descriptive profiles between the 3 treatments. The average intensity scores of the 12 texture attributes ranged from 1.5 to 7.5 and there were no significant differences between the AC and IC samples. The average intensity scores of the texture attributes, cohesiveness, hardness, cohesiveness of mass, rate of breakdown, and chewiness of the no chill fillets and tenders were significantly higher than those of either of the chilled samples. These results demonstrate that chicken breast meat from AC retains sensory flavor profile characteristics but AC results in sensory texture profile differences when compared with no-chill meat. Sensory flavor and texture profiles of AC broiler breast meat do not differ from those of IC samples when the muscles are deboned at the same time after the initiation of chilling.
    Poultry Science 07/2009; 88(6):1282-91. · 1.52 Impact Factor
  • H Zhuang, E M Savage
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    ABSTRACT: Measurements of texture properties related to tenderness at different locations within deboned broiler breast fillets have been used to validate techniques for texture analysis and establish correlations between different texture evaluation methods. However, it has been demonstrated that meat texture can vary from location to location within individual muscles. The objective of our study was to investigate the intramuscular variation and Pearson correlation coefficients of Warner-Bratzler (WB) shear force measurements within early deboned broiler breast fillets and the effect of deboning time and cold storage on the variation and correlation coefficients. Broiler breast fillets were removed from carcasses early postmortem (2 h) and later postmortem (24 h). Storage treatments of the 2 h samples included 0 d, 7 d at 3 degrees C, 7 d at -20 degrees C, and 6 d at -20 degrees C plus 1 d at 3 degrees C. The WB shears of cooked fillets were measured using a TA-XTPlus Texture Analyzer and a TA-7 WB shear type blade. Our results showed that although the average WB shear force values differed within the 0-d, 2-h fillets, compared with the variation among the fillets within the treatment, the difference within a fillet is still evidently small. The Pearson correlation coefficients were significant between the locations; however, values of the correlation coefficients depended on the paired locations. Location differences in the WB shear values and the correlation coefficient values between them changed with deboning time and cold storage. These results demonstrate that the variation of WB shear force measurements is substantial within early deboned broiler breast fillets and the Pearson correlation coefficient values of the measurements vary among the locations. Both the variation and the Pearson correlation coefficients can be affected by postmortem aging time and storage. The differences in the means between the locations in early deboned breasts are much smaller than the variation among the fillets.
    Poultry Science 02/2009; 88(1):214-20. · 1.52 Impact Factor
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    H Zhuang, E M Savage
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    ABSTRACT: Quality assessment results of cooked meat can be significantly affected by sample preparation with different cooking techniques. A combi oven is a relatively new cooking technique in the U.S. market. However, there was a lack of published data about its effect on quality measurements of chicken meat. Broiler breast fillets deboned at 24-h postmortem were cooked with one of the 3 methods to the core temperature of 80 degrees C. Cooking methods were evaluated based on cooking operation requirements, sensory profiles, Warner-Bratzler (WB) shear and cooking loss. Our results show that the average cooking time for the combi oven was 17 min compared with 31 min for the commercial oven method and 16 min for the hot water method. The combi oven did not result in a significant difference in the WB shear force values, although the cooking loss of the combi oven samples was significantly lower than the commercial oven and hot water samples. Sensory profiles of the combi oven samples did not significantly differ from those of the commercial oven and hot water samples. These results demonstrate that combi oven cooking did not significantly affect sensory profiles and WB shear force measurements of chicken breast muscle compared to the other 2 cooking methods. The combi oven method appears to be an acceptable alternative for preparing chicken breast fillets in a quality assessment.
    Journal of Food Science 11/2008; 73(8):S424-30. · 1.78 Impact Factor
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    ABSTRACT: Cold air or ice water can be used to chill poultry carcasses after slaughter. The objective of this study was to compare the effect of 2 chill methods on broiler carcass bacteria. Broiler carcasses were cut in half along the dorsal-ventral midline; one half was subjected to an ice-water immersion chill in an agitated bath for 50 min, whereas the reciprocal half was subjected to an air chill in a 1 degrees C cold room for 150 min. Total aerobic bacteria, coliforms, Escherichia coli, and Campylobacter were enumerated from half-carcass rinses. Species of Campylobacter isolates was determined by a commercial PCR method, which was followed by molecular subtyping with pulsed-field gel electrophoresis and determination of antimicrobial susceptibility to 9 drugs. Although significantly fewer of each bacterial type were detected per milliliter from immersion-chilled carcasses than from air-chilled carcasses, in each case the difference was less than 1 log(10) cfu/mL. Chilling method did not affect species; both Campylobacter jejuni and Campylobacter coli were recovered. Results of pulsed-field gel electrophoresis subtyping did not suggest that either chilling method selected for any specific subtypes; most subtypes were found on carcass halves used for both the air chill and water immersion chill. Resistance to 2 antimicrobial drugs was noted in 9 C. coli isolates, 6 from air-chilled carcass halves and 3 from immersion-chilled carcass halves. These data showed that immersion-chilled carcasses had lower numbers of bacteria; however, the difference was not large and may have been due to simple dilution. Both methods were effective for lowering carcass temperature, and neither chilling method seemed to select for specific species, subtypes, or antimicrobial-resistant Campylobacter.
    Poultry Science 06/2008; 87(5):992-8. · 1.52 Impact Factor
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    ABSTRACT: Advantages of air chilling (AC) methods over immersion chilling (IC) methods in quality retention and improvement of deboned chicken breast meat depend on experimental conditions, such as deboning time. The objective of this study was to evaluate the effect of a dry-AC method on shear force and water-holding capacity (WHC) of broiler breast meat deboned 4h postmortem compared to hot-boned (no chill) or immersion-chilled meat. Ready-to-cook broiler carcasses were hot-boned, chilled by ice water immersion (0.3 °C, 50 min) or chilled by cross-flow cold, dry air (0.7 °C, 150 min). Pectoralis (p.) major and p. minor were removed from the bone at 4 h postmortem. Shear force was measured using a Warner-Bratzler (WB) method and WHC was estimated using cooking yield, drip loss, amount of bound water (filter paper method) and water uptake (swell/centrifugation method). Regardless of muscle type, the WB shear force value of AC samples was significantly lower than that of hot-boned samples; however, there was no difference in the shear force between AC and IC. Regardless of measurement methods, there were no differences (P > 0.05) in WHC between the three treatments. These results demonstrate that when compared to no chill, AC followed by 4 h postmortem deboning can lead to a difference in WB shear values while WHC properties can be retained. For broiler breast meat deboned 4 h postmortem, AC does not result in any significant differences in shear force and WHC when compared to IC.
    International Journal of Poultry Science. 01/2008;
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    ABSTRACT: The dielectric properties, consisting of the dielectric constant (epsilon') and loss factor (epsilon''), were measured with an open-ended coaxial-line probe and impedance analyzer for uncooked broiler breast muscle pectoralis major and pectoralis minor, deboned at 2- and 24-h postmortem, over the frequency range from 10 to 1,800 MHz at temperatures ranging from 5 to 85 degrees C. The dielectric property profiles of chicken breast muscle are dependent upon the radio-wave and microwave frequencies and temperature. Increasing frequency from 10 to 1,800 MHz results in decreasing values of the dielectric constant and loss factor regardless of temperature in this range, chicken breast muscle type, or deboning time. However, the response to temperature varies with the frequency, muscle type, and deboning time. There are no differences in the dielectric constant and loss factor values at frequencies of 26 or 1,800 MHz between samples deboned at 2- and at 24-h postmortem. However, the muscle type significantly affects the average values of the dielectric constant and loss factor, with pectoralis minor having significantly higher average values. Both the deboning time and muscle type significantly affect the average values of the loss tangent (tan delta = dielectric loss factor/dielectric constant) at 26 and 1,800 MHz, with pectoralis minor having higher values than pectoralis major and 2-h samples having higher values than 24-h samples. Our quality measurements also show there are significant differences in chicken meat quality characteristics, including color, pH, drip loss, water holding capacity, and texture (Warner-Bratzler shear force value) between the different muscle types and between different deboning times in the same test. These results suggest that there is a probable potential for using dielectric property measurements to assess the quality of chicken meat.
    Poultry Science 12/2007; 86(11):2433-40. · 1.52 Impact Factor

Publication Stats

25 Citations
13.90 Total Impact Points

Institutions

  • 2007–2012
    • United States Department of Agriculture
      • Agricultural Research Service (ARS)
      Washington, D. C., DC, United States
  • 2008
    • Agricultural Research Service
      Kerrville, Texas, United States