• Journal of the Korean Society of Environmental Restoration Technology
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• v.4 no.4
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• pp.46-55
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• 2001

Analysis of fish farm influences on stream water quality may provide basic informations on watershed management to reduce environmental impact due to fish farm development and to conserve stream water quality in forested watershed area. In this research stream water qualities around Mt. Baegun area were monitored seasonally for three years. Due to the increase of pH in effluent water from the fish farm it was believed that alkalization of stream water can be accelerated by large scale development of fish farms in the forested watershed area. As a result of regression analyses, the linear equation of pH of influent and effluent water of fish farm was, pH of effluent water of fish farm = $0.6234{\times}pH$ of influent water of fish farm + 2.6263. Also, the linear equation of electrical conductivity of influent and effluent water of fish farm was electrical conductivity of effluent water of fish farm = $1.7275{\times}$electrical conductivity of influent water of fish farm - 14.007. Negative effects on stream water quality were observed by indications of increase in electrical conductivity and water temperature of effluent water from the fish farm. Decreases in physicochemical indices such as the amount of dissolved oxygen, total amount of cation and total amount of anion in effluent water from the fish farm were also negative aspects in downstream ecology. It is recommended that water purification system as well as environmentally-friendly fish farm design should be incorporated to large scale fish farm development plan in forested watershed area.

• Food Science and Biotechnology
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• v.14 no.6
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• pp.752-757
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• 2005

Changes in milk quality during storage of extended shelf life milk (ESL milk) and non-ESL milk were evaluated. No significant differences were observed between ESL and typical ultra high temperature-treated (UHT) milk in physicochemical properties including non-casein nitrogen (NCN) content, whey protein nitrogen index (WPNI), and L-ascorbic acid content. Low temperature and long time-treated milk (LTLT milk) had significantly higher NCN content and WPNI than those of UHT milk. In terms of microbial quality, yeast, molds, coliforms, and other bacteria were not detected in ESL milk during entire storage (21 days after expiration date) period at 4 and $25^{\circ}C$, while LTLT milk was more susceptible to microbial infection. Rats fed ESL milk resulted in significantly higher body weight, average daily gain, and feed efficiency than those given UHT milk. These results suggest ESL milk maintains better microbial quality than typical UHT milk, particularly during storage under extended refrigeration and at high temperature.

• Food Science of Animal Resources
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• v.32 no.5
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• pp.531-539
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• 2012

To determine the effects of various drying methods on the quality characteristics of beef jerky from low-valued cuts, Hanwoo beef shank muscles were either hot air-dried, shade-dried, or sun-dried. The physicochemical quality and microbiological safety of the Hanwoo beef jerky were analyzed during a storage of $25^{\circ}C$. Moisture content and water activity ($a_w$) of the samples decreased as the time period of storage increased, regardless of the drying condition (p<0.05). Shade-dried jerky showed higher $a_w$ compared to others after storage of 20 d (p<0.05). The pH value of hot air-dried jerky was higher than those of others (p<0.05). For color properties, sun-dried samples showed higher redness ($a^*$) and yellowness ($b^*$) compared with the properties of others (p<0.05). The hot air-dried jerky showed higher shear force values than the sun-dried or the shade-dried jerky after 10 and 20 d (p<0.05). However, the total plate counts (TPCs) of naturally dried jerky (shade and sundried) were higher than hot-air dried jerky after storage of 10 and 20 d (p<0.05). With regard to sensory properties, naturally dried jerky showed higher tenderness, juiciness, and overall acceptability scores than the hot air-dried jerky (p<0.05). In conclusion, although natural drying appears to be more susceptible to microbiological contamination than hot air-drying, the natural drying method seems to result in superior quality than the hot air drying method.

• The Korean Journal of Food And Nutrition
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• v.31 no.2
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• pp.278-283
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• 2018

The objective of this study was to evaluate quality properties of high quality rice. Seven rice varieties, Dabo, Daebo, Samkwang, Sindongjin, Sukwang, Jinsumi, and Haiami, were investigated for proximate contents and physicochemical characteristics. Moisture content was highest in the Jinsumi (13.13%). Protein and lipid content was highest in the Haiami. The amylose content of the rice cultivars was 20.15~22.51%. The degree of amylopectin polymerization (DP) was analyzed, and in all cultivars, DP 13-24 content was found to be highest, at more than 53%, whereas DP ${\geq}37$ content was lowest, at less than 5.81%. With regard to free sugar, maltose content in rice was the highest (${\geq}46%$). Toyo value of rice was highest in Samkwang, Daebo, and Jimsumi. Palatability characteristics were highest in Daebo and Jimsumi. Thus, the results of this study suggested that Samkwang, Daebo, and Jinsumi can be effectively used as processed cooked rice, though further studies should be required regarding changes in the quality of rice after cooking.

• Food Science of Animal Resources
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• v.40 no.6
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• pp.896-907
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• 2020

Imaging technique or computer vision (CV) technology has received huge attention as a rapid and non-destructive technique throughout the world for measuring quality attributes of agricultural products including meat and meat products. This study was conducted to test the ability of CV technology to predict the quality attributes of beef. Images were captured from longissimus dorsi muscle in beef at 24 h post-mortem. Traits evaluated were color value (L*, a*, b*), pH, drip loss, cooking loss, dry matter, moisture, crude protein, fat, ash, thiobarbituric acid reactive substance (TBARS), peroxide value (POV), free fatty acid (FFA), total coliform count (TCC), total viable count (TVC) and total yeast-mould count (TYMC). Images were analyzed using the Matlab software (R2015a). Different reference values were determined by physicochemical, proximate, biochemical and microbiological test. All determination were done in triplicate and the mean value was reported. Data analysis was carried out using the programme Statgraphics Centurion XVI. Calibration and validation model were fitted using the software Unscrambler X version 9.7. A higher correlation found in a* (r=0.65) and moisture (r=0.56) with 'a*' value obtained from image analysis and the highest calibration and prediction accuracy was found in lightness (r²_c=0.73, r²_p=0.69) in beef. Results of this work show that CV technology may be a useful tool for predicting meat quality traits in the laboratory and meat processing industries.

• Korean journal of food and cookery science
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• v.33 no.1
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• pp.9-19
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• 2017

Purpose: This study was conducted to obtain basic data for the quality characteristics of commercial kimchi pastes. Methods: The physicochemical, microbial, and sensory quality characteristics of kimchi paste purchased from 12 companies (KP 1-12) were investigated. Results: Commercial kimchi pastes contained a moisture content of 61.60-82.99%. The pH and titratable acidity of samples were 4.88-5.92 and 0.56-1.58%, respectively, and salinity was on average, 3%. The reducing sugar content was approximately 67.35 mg/mL, and those of KP 8 was higher by approximately 100 mg/mL. American Spice Trade Association (ASTA) value of kimchi pastes varied based on the samples. The commercial kimchi pastes contained capsaicin and dihydrocapsaicin at 1.51-7.84 and, 0.54-2.26 mg/100 g, respectively; sodium and potassium contents were 383.32-1,563.45 mg/100 g and 264.49-571.95 mg/100 g, respectively; and the Na/K ratio was 1.21-5.48. The number of aerobic bacteria and lactic acid bacteria detected from 5.00 to 8.00 log CFU/g. The number of yeast and mold detected from 0.50 to 2.66 log CFU/g. Coliform was detected at approximately 3-4 log CFU/g, whereas Escherichia coli was detected only in KP 3 and KP 7. Overall acceptability of kimchi paste showed a higher score in KP 1. The commercial kimchi pastes showed higher salinity and Na/K ratio and E. coli was detectedin some kimchi paste samples. Conclusion: Therefore, further studies are required to lower the Na/K ratio, for recipe developments, and the standardization of quality and hygiene safety of kimchi paste.

• Korean journal of food and cookery science
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• v.33 no.1
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• pp.45-53
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• 2017

Purpose: Physicochemical and microbiological qualities were investigated to compare quality characteristics of traditional with commercial soy sauce (Ganjang). Methods: Nineteen traditional products were collected from six provinces and three commercial products were purchased in domestic markets. The proximate composition, inorganic substance contents, viable bacteria, and chromaticity of the soy sauces were measured. Results: Although concentrations of crude fat and protein were not significantly different between traditional and commercial Ganjang, the moisture concentration of commercial soy sauce was significantly higher than in traditional Ganjang (p<0.05). However, the amount of ash in commercial soy sauce was significantly lower than in traditional Ganjang (p<0.05). Total nitrogen concentrations of traditional and commercial Ganjang were 0.50-1.59% and 0.86-1.26%, respectively. Concentrations of Na, Mg, K, Ca, Li, B, Fe, and Sr in traditional Ganjang were significantly higher than in the commercial products (p<0.05). The number of total bacteria in traditional and commercial Ganjang were $3.3{\times}10^1-6.4{\times}10^7CFU/mL$ and $5.5{\times}10^1-2.0{\times}10^3CFU/mL$, respectively. Bacillus cereus were below 10,000 CFU/mL in all samples, and Staphylococcus aureus was not detected. Fungi was not detected in 13 samples of traditional Ganjang and the three samples of commercial soy sauce. Although lightness, redness, and yellowness were not significantly different among the Ganjang, G10 was had the highest values (p<0.05). Conclusion: This research provided information about the quality characteristics of traditional and commercial Ganjang.

• Korean Journal of Food Science and Technology
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• v.28 no.3
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• pp.482-489
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• 1996

Dried-red pepper, whole and powdered types, was subjected to a storage-study by investigation the effects of packaging methods (polycloth & polyethylene/polycloth, whole dried-red pepper; nylon/polyethylene-lam-inated film, red pepper powder), temperature (ambient, $5{\sim}10^{\circ}C$) and gamma irradiation doses (0-10 kGy). After 6 months storage in polyclith sack at ambient temperature, all whole dried-red pepper showed quality deterioration, such as weight change, insect infestation, discoloration and chemical changes, After 2 years storage in combined packaging with polyethylene/polycloth sack of 5-7.5 kGy irradiated whole dried-red pepper at ambient temperature, however, quality deterioration was not observed. Gamma-irradiated red pepper powder (7.5-10kGy) showed a good quality in hygienic, physicochemical and organoleptic evaluation after 2 years of storage at ambient temperature.

• Food Science of Animal Resources
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• v.39 no.1
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• pp.139-150
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• 2019

This study aimed to determine the suitable point of sale and consumption of different quality grade (QG) Hanwoo short loin during aging period, based on physicochemical, sensory, and microbiological quality. Short loins obtained from the carcasses of 13 Hanwoo steers and 2 bulls with 5 different QGs (1++, 1+, 1, 2, and 3) were analyzed over 28 d. QG and aging time had significant effect on water holding capacity, color, shear force, total volatile basic nitrogen (TVBN) content, and sensory traits. Higher QG groups generally exhibited a lower shear force, nucleotide content, and water holding capacity, and higher $L^*$, $a^*$, and $b^*$ values. Acceptable tenderness (shear force <5.4 kg) in QG 1++, 1+, 1, and 2 was achieved on days 7, 14, 16, and 18, respectively, and QG 3 showed a shear force of 6.8 kg, even after 28 d. Regardless of QG, TVBN content below threshold levels (20-30 mg%) was observed throughout the 28 d aging period, while total plate counts above 7 Log CFU/g were seen at 21 d. In conclusion, it is recommended that Hanwoo beef with QG 1++, 1+, and intermediate QG (1 and 2) should be sold or consumed between 7 and 21, 14 and 21, 16 and 21 d, respectively. Beef with QG 3 should be sold or consumed within 21 d, based on microbial growth, even though it has not achieved desirable tenderness. For this reason, an additional tenderizing process is recommended before this beef is ready for consumption.

• Food Engineering Progress
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• v.21 no.4
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• pp.332-340
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• 2017

This study investigated the changes in the physicochemical properties of soybean sprout, radish, and pork loin during frozen Bibimbab production. The qualities of soybean sprout were affected by the blanching, thawing, and cooking processes, with the blanching process particularly regarded as an important process to attribute the overall quality of the soybean sprouts in the final product. High weight loss of radish was found in the thawing and cooking processes, while the weight loss was relatively lower than that of soybean sprout. However, mixing with hot rice can be attributed for the steep decrease in shear force of the radish. For pork meat, normally thermal treatment such as mixing with hot rice and cooking manifested quality deterioration. Based on the results, mixing process appeared to be the most important process which affected the final quality of the materials. To improve the quality of final frozen Bibimbab, therefore, it was recommended to freeze the food ingredient separately from rice prior to packaging, which warranted the follow up exploration.