• Food Science and Biotechnology
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• v.14 no.5
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• pp.639-644
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• 2005

The aim of this study was to investigate the effect of the myosin light chain (MLC) isoforms on the muscle fiber characteristics and meat quality traits in porcine longissimus muscle. Pale, soft, exudative (PSE) samples had a lower content of essential light chain (ELC) 1S isoforms and a higher proportion of the fiber type IIB than the reddish-pink, firm, non-exudative (RFN) samples. These compositions suggest that the PSE pork has a higher glycolytic and a lower oxidative capacity than the RFN pork. Therefore, these characteristics of PSE pork might affect the metabolic rate and meat quality traits, including protein solubility. In addition, the indicator traits of the postmortem metabolic rate were related to the ELC 1F/3F ratio ($pH_{45\;min}$: r = -0.43, P < 0.001; R-value: r = 0.53, P < 0.001). These results suggest that the MLC isoform composition can affect the postmortem metabolic rate and meat quality traits.

• Food Science of Animal Resources
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• v.23 no.4
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• pp.321-326
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• 2003

The objectives of this study were to develop restructured meat products(RMPs) using a transgluta-minase(TGase) and to improve the textural characteristics of RMPs manufactured with pale, soft, exudative(PSE) pork hams. The pH values of RMPs with PSE and normal pork were 5.94 and 6.07, respectively, and their water activity value was approximately 0.981. The RMPs had 70∼72％ moisture, 4∼5％ fat, 19∼20％ protein, and approximately 3％ ash contents. No differences in pH, water activity, chemical composition, and hunter color values were observed between RMPs manufactured with normal and PSE pork(p＞0.05). However, RMPs containing PSE pork hams had higher drip loss(％)(p＞0.05) than those with normal pork hams after 10 days of refrigerated storage. Although no differences were observed in the texture profile analysis(TPA) hardness and sensory evaluation, RMPs with PSE pork hams tended to have more pores and lower binding capacity those with normal pork. This result indicated that additional substrates or longer tumbling time(＞4 hr) for the manufacture of RMPs containing PSE pork were required for the products to have similar palatability to those with normal pork.

• Food Science and Biotechnology
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• v.18 no.2
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• pp.307-311
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• 2009

This study examined variations in postmortem meat quality characteristics and consumer sensory evaluations of different pork quality classes in fresh and cooked meat. Pale, soft, and exudative (PSE) meat had the highest drip loss, lightness, and the lowest $pH_{24\;hr}$ whereas dark, firm, and dry (DFD) meat showed the opposite results. When the fresh meat was evaluated by consumer panelists, they could only distinguish the PSE class of meat and it scored lowest in overall acceptability. However, the panelists did not consider cooked PSE or DFD pork to be unacceptable overall, indicating that consumers cannot distinguish the quality of cooked pork.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.1
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• pp.68-76
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• 2000

A total of 290 pork loins were selected to include a wide variation of quality to investigate the quality categories into which most pork falls, selection criteria for these categories and methods to objectively assess ultimate pork quality. They were probed at 24 h postmortem (PM) for the following: A) light reflectance by Danish Meat Quality Marbling (MQM), Hennessy Grading Probe (HGP) and Sensoptic Invasive Probe (SIP); B) electrical properties by NWK LT-K21 conductivity (NLT) and Sensoptic Resistance Probe (SRP): and C) pH by NWK pH-K21 (NpH). Also, measurements of % drip loss (PDL) and filter paper wetness (FPW), color brightness (L*), ultimate pH (pHu), lipid content, subjective color (SC), firmness/wetness (SF) and marbling scores (SM) were assessed. Each loin was categorized as either pale, soft and exudative (PSE), reddish-pink, soft and exudative (RSE), reddish-pink, firm and non-exudative (RFN) or dark, firm and dry (DFD). Statistically comparing coefficients of determination (CD), the results indicated that overall, the HGP predicted quality groups slightly better than MQM (CD=71 and 62% respectively), NpH and SRP were less effective (CD= 56 and 44% respectively), and SIP and NLT had the lowest values (CD=36 and 5% respectively). Combining various independent variable did not greatly improve the variation accounted for. When the data was sorted into marbling groups based on lipid content, this was not accurately predicted by any of the probe measurements. The MQM probe remained the best predictor for marbling class and accounted for about 25% of the lipid content variation. This was slightly improved to 33% when pHu was combined with MQM.

• Journal of Animal Science and Technology
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• v.55 no.2
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• pp.95-101
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• 2013

The present study was conducted to test a hypothesis that pork quality traits would be influenced by the systemic and/or local bioavailability of insulin-like growth factor-I (IGF-I), transforming growth factor-${\beta}1$ (TGF-${\beta}1$), or epidermal growth factor (EGF) before or at slaughter. To this end, 60 cross-bred female market pigs weighing approximately 110 kg were slaughtered, after which Longissimus dorsi muscle (LM) samples taken at slaughter (D 0) and blood samples taken at D -7 and D 0 were analyzed. The 60 carcasses rendered 36 RFN (reddish-pink, firm, and non-exudative), 16 RSE (reddish-pink, soft, and exudative), and 6 PSE (pale, soft, and exudative); 2 DFD (dark, firm, and dry) also were found but were excluded in subsequent experiments. The $L^*$ and drip loss were greater in PSE vs. RFN and RSE and in PSE and RSE vs. RFN, respectively, as they should (P<0.05). The $pH_{45min}$ was less in PSE vs. RFN (P<0.05); $pH_{24h}$ tended to be less in the former (P=0.09). The LM IGF-I and TGF-${\beta}1$ as well as serum EGF concentrations were less in PSE than in RFN. None of the other LM and serum concentrations of the three growth factors differed across the three pork quality categories. The LM IGF-I and TGF-${\beta}1$ concentrations and serum EGF concentration at D 0 were negatively correlated with drip loss [r = -0.36(P<0.01), -0.44 (P<0.01), and -0.32 (P<0.05), respectively]. However, none of the serum and LM growth factor variables was correlated with $L^*$ or $a^*$ (redness) of LM. Taken together, results suggest that locally expressed IGF-I and TGF-${\beta}1$ and blood-borne EGF may have a beneficial effect on postmortem water holding capacity of the muscle and that pork quality traits could be predicted to some extent from concentrations of IGF-I and TGF-${\beta}1$ in muscle and EGF in serum at slaughter.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.2
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• pp.257-262
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• 2007

The current study was conducted to investigate the optimum stunning voltage and chilling regime with emphasis on reduction in pale, soft and exudative (PSE) pork. The experiments were conducted at seven Korean major pig abattoirs using a total of 91,082 industrial population. Frequencies of PSE meat was found to be significantly (p<0.05) increased as stunning voltage was elevated from 220-240 (13.14%), 250-280 (29.32%) to 430 volts (36.74%). Chilling methods after slaughter, either with cold water showing or rapid chilling reduced PSE meat by 22% compared to a classic chiller-based slow chilling regime. The current study also revealed that chiller temperature during the first 90 minutes had a significant (p<0.001) effect on PSE incidences. Pigs chilled between -5 to $7^{\circ}C$ resulted in the lowest PSE meat (17.8%), followed by higher than $7^{\circ}C$ (21.3%) and lower than $-5^{\circ}C$ (37.5%). The current data implies that low voltage stunning method (eg., 220-240 volts), followed by rapid chilling regime, maintaining chiller temperature between approximately -5 to $7^{\circ}C$ could reduce PSE incidences.

• Journal of Animal Science and Technology
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• v.60 no.1
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• pp.30.1-30.10
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• 2018

Background: The poultry industry suffers losses from problems as pale, soft and exudative (PSE), and dark, firm and dry (DFD) meat can develop in meat as a result of short- and long-term stress, respectively. These abnormalities are impacted by pre-slaughter animal welfare. Methods: This work evaluated the effects of open vehicle container microclimate, throughout the $38{\pm}10km$ journey from the farm to the slaughterhouse, on commercially turkey transported during the Brazilian winter season. The journey was initiated immediately after water bath in truck fitted with portable Kestrel anemometers to measure air ventilation, relative humidity, temperature and ventilation. Results: The inferior compartments of the middle and rear truck regions showed highest temperature and relative humidity, and lower air ventilation. In addition, the superior compartments of the front truck regions presented lower temperature and wind chill, and highest air ventilation. The breast meat samples from animals located at the inferior compartments of the middle and rear truck regions and subjected to with water bath (WiB) treatment presented highest DFD-like and had lowest PSE-like meat incidence than those from animals located at other compartments within the container. Lower incidence of PSE-like meat was observed in birds without water bath (WoB). Conclusions: Assessment on turkeys transported under Brazilian southern winter conditions revealed that breast meat quality can be affected by relative humidity, air ventilation, temperature, and transport under subtropical conditions promoting color abnormalities and the formation of simultaneously PSE-like and DFD-like meat.

• Korean Journal of Poultry Science
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• v.26 no.1
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• pp.1-25
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• 1999

Concerns about meat quality, including chicken meat, for the human diet has led to many attempts to manipulate the carcass fat and increase the eating quality. For actual eating quality, the birds must be grown and finished in a manner that results in meat that are tender, succulent and of good flavor, as well as being free from any foreign taint, flavor or safety hazard. Tenderization treatment with high voltage(820V) electrical stimulation and prechill muscle tensioning would improve the tenderness of chicken meat. Proper programs for the withdrawal of feed and water require a team approach for maximizing yield of meat and minimizing carcass contamination. Also effding of supplemental levels of-tocopherol to poultry with vegetable or fish oils increases of desirable polyunsaturated fatty acid(PUFA) content and stablizes the meat against rancidity and fish off-flavors. The nutritional effects of varying dietary ingredients on broiler carcass fat content are also important. Increasing the levels of energy in the ration increases the carcass fat content, while increasing the proteing levels decreases carcass fat content. Supplement-tation of poultry diets with amino acids such as methionine, lysine, glycine and tryptophan as well as amino acid such as well as amino acid mixtures can reduce body fat deposition. Normal stress leads to chicken muscular damage resulting in reduced meat quality, but this can be controlled by preslaughter management practices. Feed manufactures can utilize ntilize nutrient modulation to control pale soft exudative(PSE)syndrome. Finally, the success in poultry meat production depends on the consistent achievement of carefully selected levels of quality. Quality assurance should be the wider function of incorporating quality into the production system and the combination of motivating quality into actions and operations.

• Journal of Animal Science and Technology
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• v.45 no.3
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• pp.483-490
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• 2003

The incidence of PSE(Pale, Soft, Exudative) pork by slaughter weight and handling conditions at preslaughtering stage such as fattening period, transport and lairage time were compared. The incidence of PSE pork were 24.9% when pigs were fed under 180 days and 18.9% when pigs were fed over 180 days for fattening. In the transport time from farm to slaughter house, the incidence of PSE pork were 46.6% for shorter than 30min and 45.65% for 30 min${\sim}$60 min and 35.44% for longer than 60min. The incidence of PSE pork were 55.6% for pigs had no lairage before slaughter, 33.9% for pigs held in lairage overnight. Therefore, the incidence of PSE pork were decreased by 6% with the extension of the fattening period and 9% with the transport time of longer than 1hr and 22.1% with lairage treatment before slaughter. The incidence of PSE pork were different in different location of farms and there were no significantly different in live weight, carcass weight and carcass yield between groups of lairage treatment. In conclusion, handling condition at preslaughtering stage such as extension of fattening period and lairage time were important to control pork quality and lairage treatment was not decreased the carcass yield.

• Korean Journal of Food Science and Technology
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• v.23 no.6
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• pp.661-666
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• 1991

European style fermented sausages were made with normal pork, PSE and a 50 : 50 mixture, inoculated with Lactobacillus plantarum 1-74 and Staphylococcus simulans MIII and ripened for 21 days following commercial manufacturing procedures. In all treatments, pH droped sharply between 0 and 3 days during ripening. PSE sausages showed the lowest pH and Aw at the end of ripening than other treatment groups. Protein solubility, hardness, cohesiveness and chewiness were significantly (P<0.05) low for PSE sausages. Springiness was the highest for normal sausages but the other two treatment were not different. PSE sausages had poor texture low redness value during the ripening. The added sugars apparently dropped the pH fast in PSE sausages. Total bacterial count and lactobacilli increased from 0 day to the third day of ripening. The number of Staphylococcus sp. decreased in normal sausages by the end of the ripening period. Fermented sausages with PSE meat could be produced if the mixture had lower (<50%) amounts of PSE meat. In addition, added sugar must be reduced to prevent lowering the pH to a level that will affect processing and quality attributes of fermented sausages.