• Food Science of Animal Resources
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• v.18 no.3
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• pp.248-254
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• 1998

The two hundreds and twenty two pork carcasses from commercial breed were tested to compare technical quality characteristics and relationships with meat quality parameters between PSE and normal pork classified buy 24hr postmortem conductivity($C_u$). In characteristics of PSE and normal pork by $C_u$ value, highly significant differences were found in NPPC color scale and CIE L*(p＜0.001), moderately significant differences in $C_3$ and cooking loss(p＜0.01), and significant differences were in $C_6$, CIE b*, WHC and juiciness(p＜0.05). In correlation coefficients between $C_u$ and other meat quality determining factors, $C_u$ was poorly related with $pH_1$($R^2$=0.28, p<0.001), CIE a*($R^2$=0.14, p＜0.05), b*($R^2$=0.28, p＜0.01) and cooking loss($R^2$=0.26, p＜0.01). Also, relatively low correlation coefficients were observed in $pH_u$($R^2$=0.32, p＜0.001), WHC($R^2$=0.39, p＜0.001) and juiciness($R^2$=0.41, p＜0.001). Moderately high coefficients were found in NPPC color scale($R^2$=0.59, p＜0.001) and CIE L*($R^2$=0.58, p＜0.001).

• 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.

• 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.

• Journal of Animal Science and Technology
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• v.45 no.5
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• pp.835-840
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• 2003

Two hundreds and twenty three pork carcasses of commercial breeds were studied for comparing to technical quality characteristics of pork identified by National Pork Producers Council(NPPC) scale. pH and conductance(C) were taken in 1(pH$_1$, C$_1$), 3(pH$_3$, C$_3$), 6(pH$_6$, C$_6$) and 24hr(pHu, Cu) postmortem on 4~5th thoracic vertebrae. Visual color and CIE value were estimated in longissimus dorsi(LD) muscle in 24hr postmortem on the two sites(4~5th thoracic vertebrae and last vertebrae) using National Pork Producers Council(NPPC) scale and color difference meter. Significant differences were observed in pH$_1$, pHu, Cu, CIE L$^{*}$ value, water holding capacity(WHC) and juiciness at all scales(p〈0.05). But, pH and CIE L$^{*}$value were considerably affected by postmortem time and measuring site. NPPC scale was highly related with CIE L$^{*}$(R$^2$=0.77) and WHC(R$^2$=0.66), and moderately related with C$_{u}$(R$^2$=0.59) and pH$_{u}$(R$^2$=0.54), and poorly related with pH$_3$(R$^2$=0.32), pH$_6$(R$^2$=0.28) and C$_1$～C$_6$(R$^2$=0.03~0.18).

• Journal of Animal Environmental Science
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• v.15 no.1
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• pp.37-50
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• 2009

The purpose of this study was to investigate the effects of on-farm management systems(including the farm size, stocking density of growing-finishing phase, proportion of finisher diet and type of growing-finishing building) and pre-slaughter handling(including the transportation time and loading time) on carcass grade, the incidence of PSE pork, the meat quality score for intra-muscle fat, inter-muscle fat, subcutaneous fat and score for elasticity of market pigs. For this study, 248,787 pigs of 53 different farms were used to establish the pork quality assurance program and to meet the comsumer's need. The results are summarized as follows. 1. The farm size had significant influence on carcass grade, in which showing the higher grade by increasing the farm size. However, the incidence of PSE pork were not significantly differences among the farm size. The meat quality score for intra-muscle fat, inter-muscle fat, subcutaneous fat and score for elasticity of market pigs were not significant influenced by farm size. 2. The stocking density of growing-finishing phase was statistically significant for carcass grade, in which showing the higher grade in mid density group. However, the incidence of PSE pork was higher in high density group. The meat quality score for intra-muscle fat, inter-muscle fat and elasticity of market pigs were greater in mid density groups, but not influenced by stocking density for subcutaneous fat score. 3. The carcass grade and the incidence of PSE pork were not significantly influenced by transportation time. However, transportation time significantly affected the meat quality score, the meat quality score for intra-muscle fat, inter-muscle fat, subcutaneous fat and elasticity of the carcasses were superior in more than 1 hour transportation groups. 4. At any time loading, the carcass grade and PSE incidence were not significantly differences. However, the meat quality score for intra-muscle fat, inter-muscle fat and elasticity of market pigs were superior in before 10 AM groups, but not influenced by loading time for subcutaneous fat score. 5. The proportion of finisher diet had not significant influence on carcass grade, but PSE incidence affected by proportion of finisher diet, 21 percent or more group was higher PSE incidence. The meat quality score for intra-muscle fat and inter-muscle fat of the carcasses were superior in 21 percent or more fed finisher diet groups, but elasticity score of carcass had not influenced by the proportion of finisher diet. 6. The type of growing-finishing building was affected the carcass grade and PSE incidence of the market pigs, carcass grade and PSE incidence were superior in enclosed mechanical ventilation building groups. The meat quality score for intra-muscle fat and inter-muscle fat of the carcasses were not significantly differences by the type of finishing building, but the score of subcutaneous fat and elasticity of carcass were superior in opened natural ventilation building groups. In conclusion, the results of this study suggest that we have more precise on-farm management practice and the knowledge related to pre-slaughter handling skills to reduce the stress and improve the status of welfare of market pigs.

• 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.

• Food Science of Animal Resources
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• v.38 no.4
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• pp.823-828
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• 2018

The purpose of this study was to evaluate the suitability of the released water (RW) method for measuring water-holding capacity (WHC) by pressure and filter-paper absorption within two thin plastic films. One hundred fifty pork loins with considerable variations in WHC (three pork qualities: PSE, pale, soft, and exudative; RFN, reddish-pink, firm, and nonexudative; and DFD, dark, firm, and dry; 50 pork loins in each pork quality group) were used to measure drip loss (DL)% and RW % after applying different loads (1.5, 2.0, 2.5, 3.0 and 3.5 kg). Percentages of DL and RW were significantly (p<0.05) different among pork quality groups. The RW % of 2.5 kg load sample was significantly (p<0.05) higher than that of 2.0 kg or 1.5 kg load sample. However, there were no significant (p>0.05) differences in RW % among 2.5 kg, 3.0 kg, and 3.5 kg load samples for all three pork quality groups. The RW % was highly and positively correlated (r>0.95; p<0.001) with DL %. The highest correlation was observed between DL % and RW % of 2.5 kg load sample (r=0.97; p<0.001). Among all RW loads within each quality groups, the highest correlation between DL % and RW % was observed for 2.5 kg load sample (r=0.43, 0.66, and 0.46 for PSE, RFN and DFD quality groups, respectively, p<0.001). These results imply that applying 2.5 kg load is the best for determination of RW %. It is recommended as a reference method to assess DL % of pork muscles.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.1
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• pp.77-85
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• 2000

To investigate the practical assessing method of pork quality, 302 carcasses were selected randomly to represent commercial conditions and were probed at 24 hr postmortem (PM) by Danish Meat Quality Marbling (MQM), Hennessy Grading Probe (HGP), Sensoptic Resistance Probe (SRP) and NWK pH-K21 meter (NpH). Also, filter paper wetness (FPW), lightness (L*), ultimate pH (pHu), subjective color (SC), firmness/wetness (SF) and marbling scores (SM) were recorded. Each carcass was categorized as either PSE (pale, soft and exudative), RSE (Reddish-pink, soft and exudative), RFN (reddish-pink, firm and non-exudative) or DFD (dark, firm and dry). When discriminant analysis was used to sort carcasses into four quality groups the highest proportion of correct classes was 65% by HGP, 60% by MQM, 52% by NpH and 32% by SRP. When independent variables were combined to sort carcasses into groups the success was only 67%. When RSE and RFN groups were merged so that there were only three groups (PSE, RSE+RFN, DFD) differentiating by color MQM was able to sort the same set of data into the new set of three groups with 80% accuracy. The proportions of correct classifications for HGP, NpH and SRP were 75%, 61% and 35% respectively. There was a decline in predication accuracy when only two groups, exudative (PSE and RES) and non exudative (RFN and DFD) were sorted. However, when two groups designated PSE and non-PSE (RSE, RFN and DFD) were sorted then the proportion of correct classification by MQM, HGP, SRP and NpH were 87%, 81%, 71% and 66% respectively. Combinations of variables only increased the prediction accuracy by 1 or 2% over prediction by MQM alone. When the data was sorted into three marbling groups based on SM this was not well predicted by any of the probe measurements. The best prediction accuracy was 72% by a combination of MQM and NpH.

• 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.

• 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.