• Journal of Environmental Health Sciences
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• v.26 no.2
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• pp.97-107
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• 2000

PCBs [Polychlorinated biphenyls] are halogenated aromatic compounds with the empirical formula C12H10-nCln(n=1~10), and are a mixture of possible 209 different chlorinated congeners. PCBs were widely used as dielectric fluids for capacitors, transformers, plasticizers, lubricant inks, and paint additives. once released into the environment, PCBs persist for years because they are so resistant to degradation. In addition to their high degree of lipophilicity. In 1970s, the worldwide production of PCBs seem to be still in use. The environmental load of PCBs was prohibited since 1983 in Korea. In spite of these actions, many PCBs seem to be still in use. The environmental load of PCBs will continue to be recycled through air, land, water, and the biosphere for decades to come. This study was conducted to measure the concentrations of PCBs I the serum samples of 112 women by GC/MSD(Hewlett Packard 5897 Gas Chromatography-Mass Chromatography Detector) and CG/ECD(Hewlett Packard 5890 series-II gas chromatography-Electron capture detector, U.S.A). The main results of this study were as follows; The mean and standard deviation of serum PCBs were 3.613, 0.759 ppb, respectively and median of it was 3.828 ppb. The correlation coefficients of the concentrations of 13 PCB congeners ranged from 0.7913 to 0..9985 and were significantly correlated between each items(p=0.0001). The PCB concentrations were positively associated with age(simple linear regression; R2=0.86, =0.08023, p<0.001) and with total lipids in serums(simple linear regression; R=0.7058, =0.00486, p<0.001). The age adjusted model (Y=$\beta$0+$\beta$1age+$\beta$2X) was applied for possible predictors of PCBs levels in serum. For BMI(Body Mass Index), major residential area, and fish, meat, and dairy consumption, there was no association with PCBs levels, Also there was negative association for the number of pregnancy and lactation period with PCBs levels.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.9
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• pp.1461-1466
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• 2013

In this study, we ascertained the characteristics of crude protease extracted from fruits (fig, kiwifruit and pineapple) as well as traditional Korean fermentation starters (bio nuruk, traditional nuruk, meju and rice koji) to determine their suitability for industrial application. Crude protease extracted from traditional Korean fermentation starters was found to have a higher optimum temperature ($70^{\circ}C$) and salt concentration (1~3%) but a lower optimum pH (3~6) value compared to the corresponding values for the protease extracted from fruits. On comparison, the total activities of protease per gram unit follow the order: bio nuruk> rice koji> traditional nuruk> fig> pineapple> meju> kiwifruit. Based on our results, we conclude that protease extracted from traditional Korean fermentation starters has potential for application in food industry, for example, as a meat tenderizer for sausage manufacturing and as a protease for cheese production.

• Applied Biological Chemistry
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• v.35 no.5
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• pp.339-345
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• 1992

In order to enhance the processing quality and utility of alaska-pollack meat, the optimum conditions for the preparation of pronase hydrolysate and the synthesis of plastein were investigated. The optimum temperature and pH for the hydrolysis of alaska-pollack by pronase were $40^{\circ}C$ and pH 7.0. The reaction time and enzyme concentration were 4 hr and 1,000 units per g of substrate. Under the above optimum conditions alaska-pollack was hydrolyzed by pronase yielding a hydrolytic degree of about 89%. Pronase hydrolysate was employed as substrate for plastein synthesis. The 30% pronase hydrolysates were adjusted to pH 7 for fruit-bromelain and pH 5 for stem-bromelain, and then plastein were synthesized by 1% bromelain at $40^{\circ}C$ for 24 hr. The plasteins synthesized by fruit- and stem-bromelain were consisted of peptides having average peptide length of 22.6 and 20.8 under the optimum synthetic conditions. The plastein synthesis reaction reduced considerably the bitterness of pronase hydrolysate.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.17 no.2
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• pp.33-37
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• 2011

Real time control logic of microbial shelf life of a perishable food, seasoned pork meat has been formulated which exploits monitoring of $CO_2$ concentration of the package. The potential of the proposed logic was examined for storage at dynamic temperature conditions. The start of increase in $CO_2$ production rate from the food or rate of package $CO_2$ concentration change was found to coincide with the point of microbial quality limit and could be used as an index of microbial shelf life determination. This also corresponded to lag time of $CO_2$ concentration change or time for the $CO_2$ concentration to reach a certain value. The application potential of the proposed logic was confirmed for a sensor system to measure on real time and transmit the $CO_2$ concentration wireless to the computer system.

• Korean Journal of Organic Agriculture
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• v.26 no.1
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• pp.19-31
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• 2018

In general, an increase in consumer income increases interest in safe foods and increases consumption of environmental friendly foods. Meanwhile, even in Malawi, interest in safe food and environmentally friendly food has been increasing due to increase in per capita income, but research related to this has not been done yet. The purpose of this study is to estimate the value of environmentally friendly foods in Malawi consumers. For this purpose, we surveyed the consumption patterns and estimated the value of organic chicken for consumers visiting supermarkets. As a value estimation technique, Contingent Valuation Method (CVM) was used. Probit model analysis showed that price, expenditure on regular chicken, and knowledge of organic food affect the willingness to pay for organic chicken. CVM analysis shows that Malawi supermarket consumers are willing to pay MK2,514 (3.59) dollars per kilo of organic chicken, which is 25.7% higher than the average price of a regular chicken. Thus, Malawi supermarket consumers can deduce that they have a higher value for environmentally friendly food than regular food. These findings can be used in formulating policies on food safety by government officials, organic chicken meat marketing strategies by supermarket mangers, decision making to enhance organic food production by producers, in order to develop organic food industry.

• Food Science of Animal Resources
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• v.30 no.2
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• pp.236-242
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• 2010

The objective of this study was to investigate the potential of the application of kimchi LAB as starter culture in the production of fermented sausages. For this, the solid-state model media composed to simulate the substantial conditions of meat mixtures were fermented for 120 h after the treatment with different concentrations of kimchi (0.5, 1.0, 1.5, 3.0, and 5.0%) and lyophilized kimchi-powder (0.2 % and 0.5%). During the fermentation period, the growth of total viable cells and LAB, and the changes of pH and titratable acidity were investigated. The initial LAB counts ranged from 7.18 to 8.34 Log CFU/ mL for kimchi media and from 6.93 to 6.94 Log CFU/mL for kimchi-powder media depending on the added concentrations. The kimchi LAB in this study were not influenced by the immobilized condition for their adaptation and growth by showing no lag phase and thus acted similar as in the submerged medium. The initially increased counts reached around 9 Log CFU/ mL in 12 h independent of the concentrations of a ded kimchi. However, the growth and metabolic activity of kimchi-powder LAB were influenced by the immobilized condition. Supposedly, as the nutrient supply in solid-state depended solely on diffusion, these differences in the souring properties were caused by the LAB topography in the medium matrix. Nevertheless, the differences in the numbers of LAB between two media were less than 0.5 Log units and the pH drop in the solidstate batches was quite rapid and reached low values. Therefore, it can be assumed that kimchi and kimchi-powder LAB showed the utility as the substitute of commercial starter culture even without a rehydrating pretreatment.

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.12
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• pp.1933-1941
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• 2019

Objective: This study was conducted to evaluate quality characteristics of cured pork loin with natural nitrite source from Swiss chard. Methods: Pork loin was cured in brine and the ratio of water and fermented Swiss chard (FSC) solution in the brine was changed by 4:0 (control), 3:1 (T1), 1:1 (T2), 1:3 (T3), 0:4 (T4), and pickled samples with 0.012% sodium nitrite (PC, positive control) and nitrite free brine (NC, negative control) were considered as the control. Results: The pH values of cured pork loins with FSC were decreased with increasing addition level of FSC. Cooking loss was not significantly different among all treatments. T4 had the lowest value in moisture content and lightness value and the highest value in curing efficiency. The redness value of T4 was not significantly different from that of PC in raw. After cooking, however, it was higher than that of PC. The yellowness value of cured pork loin added with FSC was increased with increasing level of FSC. Volatile basic nitrogen content of cured pork loin added with FSC was higher than PC and NC. Thiobarbituric acid reactive substance value of cured pork loin added with FSC was decreased with increasing FSC level. Residual nitrite level and shear force were increased with increasing FSC level. In the sensory evaluation, sensory score for flavor, off-flavor, chewiness, juiciness, and overall acceptability were not significantly different among all treatments. However, sensory score for color was increased when the concentration of FSC added to pork loin was increased. Conclusion: The FSC solution had a positive effect on redness and lipid oxidation. As shown by the results in protein deterioration and sensory, Swiss chard can replace sodium nitrite as natural curing agent.

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.12
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• pp.1882-1888
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• 2019

Objective: An experiment was conducted to evaluate the effects of increasing levels of crude glycerin (0%, 6%, 12%, and 18%) used as a substitute for corn in lamb feed on the quantitative characteristics of the carcass. Methods: A total of 40 crossbred Santa $In{\hat{e}}s$ lambs that were four months old with a mean initial weight of $21.0{\pm}0.8kg$ were randomly distributed in four treatments with ten replicates. The animals were slaughtered after 66 days of confinement. The effects of crude glycerin as a replacement for corn in the diet of the lambs on the carcass characteristics, commercial cut weight and yield and carcass measurements were studied. Results: There was an increasing linear effect for body weight at slaughter with the replacement of corn by crude glycerin. The dry matter and metabolizable energy intakes, weight of the empty body, hot carcass weight and cold carcass weight showed a quadratic effect, with maximum crude glycerin levels estimated at 10.9%, 9.8%, 10.83%, 11.78%, and 11.35%, respectively. The initial pH was not influenced by the replacement of corn for crude glycerin, while the final pH presented a quadratic effect. The other parameters of the carcass and the weights and yields of commercial cuts were not influenced. There was also no effect of the diets on carcass morphometric measurements, except for the thoracic perimeter and the carcass compactness index, which presented quadratic and linear effects, respectively. Conclusion: Crude glycerin can replace up to 18% of corn because it favours muscle tissue deposition without promoting changes in the main carcass characteristics of lambs.

• Animal Bioscience
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• v.34 no.5
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• pp.904-913
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• 2021

Objective: Marbling or intramuscular fat (IMF) has been widely reported to directly impact the sensory acceptance of meat. This study was carried out to determine the physical and sensory characteristics of ribeye, Longissimus dorsi steaks obtained from four different cattle breeds namely Wagyu, Angus, Brahman, and Malaysian local beef, the Kedah-Kelantan (KK). Methods: The degree of marbling was determined by using an established combined camera-image analysis technique while instrumental texture determination was carried out by using Warner-Bratzler shear force analysis. Sensory evaluation of the beef steaks was performed following a quantitative descriptive analysis incorporating 10 trained consumer panelists. Results: Wagyu was found to possess the highest (p<0.05) percentage of IMF at 33.90% and the lowest shear force (raw = 5.61 N/㎟; cooked = 14.72 N/㎟) followed by Angus (20.87%), Brahman (12.17%), and KK (p<0.05, 6.86%). The difference in sensory properties of the four steaks was evident, with Wagyu appearing to be highly correlated with most sensory attributes measured namely sustained buttery, tooth-packing, chewiness, juiciness, tenderness, mouthfeel, oiliness, and overall acceptability. The Malaysian local beef, KK was found to be less acceptable (p<0.05), although most of its sensory attributes were found similar (p>0.05) in appearance, aroma, texture, juiciness, and flavour to the cooked steak from Angus and Brahman. Conclusion: This present study demonstrated the role of IMF in determining the quality and sensory acceptance of beef from different cattle breeds. These data have provided new information and further understanding on the physical and sensory quality of Malaysian local beef.

• Journal of Animal Science and Technology
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• v.60 no.12
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• pp.30.1-30.11
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• 2018

Background: Recently, as production costs have been increasing owing to rising feed prices worldwide, shortening the age of slaughter has been recognized as a way to increase farm income. In Korea, the raising period for Hanwoo steers is over 31 months with the delay of weaning and castration stated as one of the reasons for the increase in the raising period. Thus far, studies on age of weaning and castration have been conducted individually, and there have been no studies on the combined effects of weaning and castration ages on the growth performance and carcass characteristics in Hanwoo steers. Methods: Weaning ages were calculated at 80 or 130 days of age, and castration ages were calculated at 90 days and 180 days of age. Calves were allocated to one of the four treatment groups: W80C90 (weaning at 80 days of age and castration at 90 days of age), W80C180, W130C90, and W130C180. Results: For the entire experimental period, weaning and castration ages did not significantly affect growth performance of Hanwoo steers. In addition, weaning and castration ages did not affect the overall yield and quality traits of carcass in Hanwoo steers. Conclusion: Weaning and castration ages had small effects on growth performance and carcass characteristics in Hanwoo steers. Therefore, the early weaning and castration ages are recommended to reduce the slaughter age without any negative effects on meat quality grade.