• Food Science of Animal Resources
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• v.34 no.1
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• pp.73-79
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• 2014

This study was performed to evaluate the quality characteristics of three deboned categories of chicken thigh meat: one which was slaughtered and deboned in the same plant (fresh); one which was slaughtered, deboned, frozen, and thawed in the same plant (frozen-thawed); and the last which was slaughtered in a plant, deboned in a different plant, but then transferred to the original plant (fresh-outside). Surface color, drip loss, 2-thiobarbituric acid reactive substances (TBARS) value, sensory evaluation, and total aerobic bacterial counts of the chicken samples were determined. Moreover, the torrymeter was used to measure the differences in freshness of the chicken meat. The surface color and the TBARS values did not show significant differences among the three categories. However, the total aerobic bacterial counts of fresh-outside and frozen-thawed chicken meat were significantly higher than the fresh chicken meat on the first storage day, and the drip loss of frozen-thawed chicken meat was significantly higher than the fresh-outside and fresh chicken meat. In addition, the sensory evaluation of frozen-thawed chicken meat was significantly lower than the fresh-outside and fresh chicken meat. Torrymeter values were higher in fresh chicken meat than fresh-outside and frozen-thawed chicken meat during the storage period. These results indicate that the quality of frozen-thawed chicken meat is comparatively lower than the fresh chicken meat, and the torrymeter values can accurately differentiate the fresh-outside and frozen-thawed chicken meat from the fresh ones.

• Food Science of Animal Resources
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• v.31 no.1
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• pp.27-31
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• 2011

To differentiate between frozen-thawed and fresh broiler breast fillets, different methods such as optical microscopy and measurement of drip loss, pH, torrymeter and K-value were performed. A total of 10 samples of fresh and frozen-thawed breast fillets were stored in a refrigerator ($4^{\circ}C$) for 5 d. Optical microscopy of the frozen-thawed breast fillets found structural changes caused by ice crystals, which may have significantly increased drip loss compared to fresh breast fillet. The pH and K-value could not be distinguished between the two breast fillets during storage. However, the torrymeter values of the fresh and frozen-thawed breast fillets were significantly different (p<0.05). The results indicate that both optical microscopy and torrymeter measurement can be effective methods for differentiating between fresh and frozen-thawed breast fillets. However, optical microscopy may be difficult to implement in the marketplace since it requires much time and effort. Thus, the determination of the torrymeter value is the easiest and most rapid instrumental method among those tested for the differentiation of frozen-thawed chicken breast fillet from fresh one.

• Food Science of Animal Resources
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• v.33 no.1
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• pp.96-102
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• 2013

The possibility of instrumental differentiation of duck breast meat treated with different processing and storage conditions was investigated for industrial application. Duck breast meats, which were 1) refrigerated (fresh) after slaughter, 2) fresh but applied the torching process for the removal of remaining feathers (fresh-torched), and 3) frozen and thawed (frozen-thawed), were prepared and the torrymeter value and other quality factors were assessed. The torrymeter values of both duck breast meat and skin showed the lowest in frozen-thawed sample during the whole storage period. The drip loss of frozen-thawed sample was higher than those of fresh or fresh-torched ones. The number of total aerobic bacteria was lower in fresh-torched than fresh but both were not different from frozen-thawed at day 1 while no difference found thereafter. Sensory score of frozen-thawed sample was the lowest. The correlation analysis among the torrymeter value and quality factors of duck breast meat revealed that the torrymeter value is closely related with the total aerobic bacterial number, lipid oxidation, drip loss, and storage period but not with color. The results indicate that once the duck breast meat was frozen then thawed, drip loss and sensory quality can be affected and the torrymeter value can differentiate frozen-thawed from fresh and freshtorched duck breast meat.

• Journal of Broadcast Engineering
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• v.25 no.3
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• pp.418-427
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• 2020

The measurement of meat freshness at meat markets is important for the health of consumers. Currently a variety of sensors have been studied for the measurement of the meat freshness. Therefore, the analysis of sensor data is needed for the reduction of measurement errors. In this paper, we analyze the freshness measurement data of ten sensors based on deep learning. The measured data are composed of beef, pork and chicken, whose reliability and noise-robustness are examined by a deep neural network. Further, to search for multiple sensors better than a torrymeter, PCA (principle component analysis) is carried. Then, we validated that the performance of the three sensors outperforms the torrymeter in the experiment.

• Korean Journal of Poultry Science
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• v.47 no.2
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• pp.69-74
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• 2020

The current study was conducted to evaluate the effect of music enrichment on the live body weight of chickens and meat quality grade of the carcasses. Fourteen flocks at four broiler farms with identical windowless houses were provided with identical starter and finisher diets. These were either exposed to classical music or not exposed to any music from the starter to slaughter age. At 30 days posthatch, the chickens were transported from farms to a slaughterhouse. Two hundred carcasses from each flock were randomly selected for measurement of the carcass traits by the licensed meat inspectors at the slaughterhouse. The live body weights at the slaughter age were not significantly different between the two treatments. In addition, music enrichment did not affect meat freshness (i.e., torrymeter values) nor did it affect other carcass trait variables including percentage of bruises, flesh blemishes, abnormalities, and quality A grade. In conclusion, music enrichment did not affect the body weight or carcass quality of broiler chickens.

• Food Science of Animal Resources
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• v.42 no.6
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• pp.953-967
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• 2022

The objective of this study was to determine effects of aging methods (wet-aged, dry-aged, and packaged dry-aged) during 60 d on quality traits and microbial characteristics of beef. Wet-aged beef was packed by vacuum packaging and stored in a 4℃ refrigerator. Dry-aged beef was used without packaging. Packaged dry-aged beef was packaged in commercial bags. Dry-aged and packaged dry-aged samples were stored in a meat ager at 2℃-4℃ with 85%-90% relative humidity. Meat color, crust thickness, aging loss, cooking loss, Warner-Bratzler shear force (WBSF), texture profile analysis, Torrymeter, meat pH, water activity, volatile basic nitrogen (VBN), thiobarbituric acid reactant substances (TBARS), and microbial analysis were measured or performed every 15 d until 60 d of aging time. Meat color changed significantly with increasing aging time. Differences in meat color among aging methods were observed. Aging losses of dry-aged and packaged dry-aged samples were higher than those of wet-aged samples. Wet-aged beef showed higher cooking loss, but lower WBSF than dry-aged and packaged dry-aged beef. VBN and TBARS showed an increasing tendency with increasing aging time. Differences of VBN and TBARS among aging methods were found. Regarding microbial analysis, counts of yeasts and molds were different among aging methods at the initial aging time. Packaged dry-aged and dry-aged beef showed similar values or tendency. Significant changes occurred during aging in all aging methods. Packaged dry aging and dry aging could result in similar quality traits and microbial characteristics of beef.

• Korean Journal of Poultry Science
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• v.41 no.3
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• pp.159-164
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• 2014

This study was conducted to investigate whether water chilling had effect on water retention, freshness or internal temperature of chicken carcasses during chilling or storage in two different chicken processing plants (designated as A and B). A total of 240 carcasses from chicken processing plants (n = 120 per chicken processing plant) was randomly sampled and evaluated the effect of water chilling on carcass characteristics (i.e., water retention, water loss or freshness during chilling or storage). Torrymeter value was used as an indicator of freshness in chicken carcasses. Water chilling did not affect carcass water retention between the processing plants. However, chicken carcasses processing in B plant exhibited significantly higher freshness (p<0.05) compared with those in A plant. This difference in freshness was mainly due to the longer transit time through the water chiller in A versus B plants. Water loss of carcasses during storage was not different between plants. It was found that carcass freshness can be affected by water chilling time as manifested in this study. Further study is warranted to see whether freshness or microbiological status of chicken carcasses may be affected depending on the chilling methods, i.e., air or water chilling.

• Korean Journal of Poultry Science
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• v.42 no.4
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• pp.347-352
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• 2015

This study was first conducted to investigate the effect of post-mortem storage time of chicken meat on the quality of chicken breast, and to determine whether the current grading rule that is 'using the chicken meat within 2 day post-mortem (PM)' is appropriate or not at meat processing plants. Different methods such as freshness, lightness ($L^*$), total number of microbes, 2-thiobarbituric acid reactive substances (TBARS), shear force and cooking loss were performed. Forty samples of different PM time (0~4 day) of chicken meat were stored in the refrigerator ($3^{\circ}C$). As a result of comparing the chicken meat of 2 day and 3 day PM, torrymeter value was 6.9 and 7.0, respectively. The other values are also as follows: lightness ($L^*$) 60.22 and 60.51, total number of microbes 4.20 and $4.31log_{10}CFU/g$, TBARS value 0.056 and 0.071 mg MDA/kg, shear force 1.43 and $1.59kg/cm^2$, and cooking loss 17.24 and 15.66%, respectively. As a result, these two groups were not significantly different (P<0.05). TBARS value of the chicken meat of 4 day PM was 0.088 mg MDA/kg which is significantly higher compared to 2~3 day PM (P<0.05). Thus, the result of the study suggests that using the chicken meat within 3 day PM is also possible. If the grading rule that is 'using the chicken meat within 2 day post-mortem (PM)' is changed to 3 day PM, it will allow processing plants and distributors to more flexibly use or distribute chicken meat.