• Korean Journal of Ecology and Environment
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• v.45 no.2
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• pp.218-231
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• 2012

The objectives of this study were to evaluate the physico-chemical water quality, trophic and tolerance guilds in the control ($C_o$) and impacted streams of the abandoned mine, along with the ecological health, using a multimetric health model and physical habitat conditions of Qualitative Habitat Evaluation Index (QHEI), during the period of three years, 2005~2007. Also, eco-toxicity ($EE_t$) enclosure tests were conducted to examine the toxic effects on the outflows from the mine wastewater, using the sentinel species of Rhynchocypris oxycephalus, and we compared the biological responses of the control ($C_o$) and treatment (T) to the effluents through a Necropybased Health Assessment Index ($N_b$-HAI). Tissue impact analysis of the spleen, kidney, gill, liver, eyes, and fins were conducted in the controlled enclosure experiments (10 individuals). According to the comparisons of the control ($C_o$) vs. the treatment (T) in physicochemical water quality, outflows from the abandoned mine resulted in low pH of 3.2, strong acid wastewater, high ionic concentrations, based on an electrical conductivity, and high total dissolved solid (TDS). Physical habitat assessments, based on Qualitative Habitat Evaluation Index (QHEI) did not show any statistical differences (p>0.05) in the sampling sites, whereas, the $M_m$-EH model values in a multimetric ecological health ($M_m$-EH) model of the Index of Biological Integrity (IBI), using fish assemblages, were 16~20 (fair condition) in the control and all zero (0, poor condition) in the impacted sites of mine wastewater. In addition, in enclosure eco-toxicity ($EE_t$) tests, the model values of $N_b$-HAI ranged between 0 and 3 in the controls during the three years, indicating an excellent~good condition (Ex~G), and were >100 (range: 100~137) in the impacted sites, which indicates a poor condition (P). Under the circumstances, organ tissues, such as the liver, kidney, and gills were largely impaired, so that efficient water quality managements are required in the outflow area of the abandoned mine watershed.

• Food Science and Preservation
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• v.22 no.3
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• pp.392-398
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• 2015

The physicochemical properties of spray-dried rice flour with Lactobacillus plantarum CGKW3 were investigated. Amylose and damaged starch contents of spray-dried rice flour (S10, S20, S30, and S50) with L. plantarum CGKW3 were 14.18~17.75% and 24.65~34.08%, respectively. The particle size of spray-dried rice flour was $82.28{\sim}131.17{\mu}m$. The rice flour with L. plantarum CGKW3 showed a good powder flowability. The water absorption and water solubility of spray-dried rice flour were 1.96~2.13 and 9.91~21.95%, respectively. Thermal properties measured by differential scanning calorimeter revealed that the enthalpy (${\Delta}H$) for starch gelatinization were highest in the rice flour (S50) with L. plantarum CGKW3. When compared, the viable cell number of spray-dried rice flour were found to be in the following order: S10 (5.78 log CFU/g) < S20 (6.38 log CFU/g) < S30 (6.69 log CFU/g) < S50 (7.11 log CFU/g). The survaival rate of L. plantarum CGKW3 was 60.02-73.85%, which reflected the improvement in the quality of rice flour with an increase in treatment concentration. Based on our results, spray-dried rice flour with L. plantarum CGKW3 could be used in various types of rice foods.

• Food Science and Preservation
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• v.24 no.3
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• pp.464-471
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• 2017

The purpose of this study was to evaluate the effect of superheated steam drying on physicochemical and microbial characteristics of Korean traditional actinidia (Actinidia arguta) leaves. Actinidia leaves were dried at steam temperature of $350^{\circ}C$ and oven temperature of $150^{\circ}C$ for 40-200 sec. Moisture content and water activity decreased with increasing the drying time, while color values including L, a, and b values and total color difference (${\Delta}E$) increased as drying time increased. The relationship between moisture content and water activity showed an exponential fit with high correlation vlaue ($R^2=0.9909$). Total phenolics and flavonoids content and antioxidant activity such as DPPH radical scavenging activity, ABTS radical scavenging activity, and FRAP assay of dried actinidia leaves increased with increasing the drying time up to 160 sec, but dramatically decreased at drying of 200 sec. The numbers of total areobic bacteria of leaves was not detected at drying time over 120 sec and coliform of all the samples was not detected. As a results, the superheated steam was an very effective drying method of increase to the nutritional and sanitary quality of dried Korean traditional actinidia leaves.

• Korean Journal of Environmental Agriculture
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• v.1 no.1
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• pp.22-30
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• 1982

Water quality of downstream of the Nagdong river, using for agricultural irrigation of the Gimhae plain, were observed. Water temperature, turbidity, residue, pH, BOD, COD, DO, hardness, chloride, sulphate, phosphate, inorganic nitrogenous compounds, sodium, general bacteria, E. coli and heavy metals of the water were investigated at Daejeo, Sikman, Bongrim, Noksan, Machal and Jangyou pumping stations in the Gimhae plain in May, July and October, 1981. The results obtained were as follows; 1) Average value of analyzed components of the water at all sampling sites were 7.8 pH, 6.3 ppm BOD, 6.5 ppm COD, 6.4 ppm DO, 231 ppm hardness, 582 ppm Cl-, 412 ppm $SO_4--$, 2.32 ppm $PO_4---$, 3.8 ppm $NH_4+,\;478\;ppm\;Na+$, 2964 No. /100 ml total coliform, 0.0040 ppm Cd, 0.0066 ppm Pb, respectively. 2) The most heavily polluted site of all investigated ones was Sikman. It seemed to be caused by the vast quantity of wastewater discharged from industrial district in Gimhae city. The next polluted sites were Bongrim, Daejeo and Noksan, and comparatively less polluted sites were Machal and Jangyou, judging from both appearance and physicochemical observation. 3) At Sikman, the most heavily polluted site, average value of components were 8.0 pH, 8.1 ppm BOD, 8.2 ppm COD. These values were close to the limit point of agricultural water quality standard of 8.0 ppm BOD (COD). 4) Any apparent variation was not observed by the sampling season in most components except DO and $NH_4+$. DO of October was higher than that of May or July but $NH_4+$ was low. 5) $NH_4+$ content was comparatively high in downstream of the Nagdong river of which water is used as the agricultural irrigation in the Gimhae plain. Therefore, fertilizer application on the farming land must make account of nitrogen content of the irrigation water 6) It was considered that chloride and sodium contents would not influence the crop cultivation in common season, but in dry season irrigation must be done carefully.

• Korean Journal of Ecology and Environment
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• v.37 no.1 s.106
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• pp.26-35
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• 2004

We investigated the effect of physicochemical environmental factors on the community dynamics of phytoplanktons and bacteria at the Hoeya Dam Reservoir, a drinking water reservoir for Ulsan city. Water samples were collected and analyzed every two to four weeks at three sites along the reservoir from April to October, 2001. During the study period, the Secchi depths were between 0.4 and 3.5 m. At the surface layer of water column, temperature ranged 10.2 ~ $32.0^{\circ}C$, pH 7.3${\sim}$9.6, dissolved oxygen 5.5 ${\sim}$ 12.4 mg $L^{-1}$, $BOD_5$ 0.8 ${\sim}$ 5.0 mg $L^{-1}$, $COD_{Mn}$ 3.7 ${\sim}$ 10.0 mg $L^{-1}$, and Chl-a 8.9 ${\sim}$ 60.9 mg $m^{-3}$. At the bottom layer, temperature varied 7.2 ${\sim}$ $28.9^{\circ}C$, pH 7.1 ${\sim}$ 9.3, dissolved oxygen 0.6 ${\sim}$ 9.7 mg $L^{-1}$, $BOD_5$ 0.8 ${\sim}$ 4.5 mg $L^{-1}$, $COD_{Mn}$ 3.9 ${\sim}$ 10.0 mg $L^{-1}$, and Chl-a 4.3 ${\sim}$ 81.9 mg $m^{-3}$. The numbers of phytoplanktons were 7.4${\pm}10^2{\sim}2.6{\pm}10^5$ cells $mL^{-1}$ at surface and 2.5${\pm}10^2{\sim}2.4{\pm}10^4$ cells $mL^{-1}$ at bottom, and were positively correlated with water temperature and Chl- a concentration. Genus Stephanodiscus and genus Oscillatoria dominated on April and on May, respectively. Cyanobacterial blooms of Aphanizomenon, Microcystis, Anabaena were observed from June to early September, and thereafter Stephanodiscus and Aulacoseiral dominated again. Total microbial counts ranged 1.73${\pm}10^4{\sim}1.68{\pm}10^5$ cells $mL^{-1}$, and were positively correlated with water temperature and phytoplankton counts at surface water. Heterotrophic plate counts (HPCs) ranged 30${\sim}4.1{\pm}10^3$ CFU $mL^{-1}$, and were positively correlated with $BOD_5$ and $NO^3\;^-$-N concentration at bottom water. Unlike the total microbial counts, the numbers of fecal coliforms and fecal streptococci as well as HPCs were higher at the bottom than the surface layer and were highest at the upper a site among the three sampling sites. Since the concentrations of fecal coliforms and streptococci were still high at the bottom of site c, where intake for water treatment plant is located, it appeared that special management of water treatment processes may be needed especially after strong rainfall.

• Food Science and Preservation
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• v.24 no.8
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• pp.1067-1078
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• 2017

This study was carried out to investigate the physicochemical and antioxidant properties of fermented milk with addition of hot water extract of Cordyceps militaris grown upon Tenebrio molitor. The general components of Cordyceps militaris grown upon Tenebrio molitor are moisture 10.85%, crude protein 18.44%, crude fat 2.07%, crude ash 5.46%. The DPPH radical scavenging activities of different solvents were the highest (74.81 EDA%) with hot water extract sample. The acidity of fermented milk was high with increasing amount of extracts. The pH of fermented milk reached 4.60-4.66 after 4 h of fermentation, and the number of lactic acid bacteria was highest (11.70 log CFU/mL) with 1% fermented milk. The moisture content of fermented milk showed no significant difference. In addition, contents of crude protein were not significantly different according to addition amount. Regarding Hunter's color values, L value decreased as the amount of extract increased, whereas a value and b value increased. The content of free amino acid increased with increasing amount of extract. The DPPH free radical scavenging ability and ABTS free radical scavenging ability of fermented milk were significantly different as the addition amount of extract increased. In the sensory evaluation, fermented milk containing 1% of extract showed the highest preference.

• Food Science and Preservation
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• v.24 no.1
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• pp.84-92
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• 2017

Chicken breast jerky (CJ) was prepared by drying chicken breast at $50^{\circ}C$ for 9 hrs after marinating it in a various sweetening sauce including white sugar (WS), brown sugar (BS), rice syrup (RS), fructooligosaccharide (FO), pineapple concentrate (PC), Rubus coreanus extract (RCE), or honey (H), and its physicochemical and sensory properties were investigated. The CJ was found to contain 22.5-25.0% moisture, 41.0-46.6% protein, and 0.4-1.0% fat, which indicates that it could serve as a high-protein and low-fat snack. The type of sweeteners significantly affected the yield, pH, total viable cell count, and water activity of the CJ, showing ranges of 40.9-50.1%, 5.2-5.9, $2.5-6.2{\times}10^4CFU/g$, and 0.74-0.81, respectively. Both the water activity and pH were the lowest in CJ-RCE where of the highest in CJ-WS. The cohesiveness, springiness, and chewiness of the CJ significantly differed depending on the type of sweeteners (p<0.05). CJ-RCE showed the best taste and overall acceptability in a sensory test. After storage at $50^{\circ}C$ for 2 weeks, thiobarbituric acid reactive substance (TBARS) content (58.3 malondialdehyde (MDA) mg/kg) of CJ-RCE was much lower than those of control beef (75.6 MDA mg/kg) and pork jerky (98.0 MDA mg/kg), showing the good oxidative stability of CJ-RCE. Overall, marination in RCE sauce was suitable for the preparation of CJ with good quality in terms of its water activity, fat and protein contents, sensory property and oxidative stability.

• Fisheries and Aquatic Sciences
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• v.4 no.4
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• pp.238-245
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• 2001

Optimal conditions for processing. of seasoned-dried Pacific saury treated with liquid smoke (T2) were evaluated by physicochemical and microbial experiments and sensory evaluation, comparing with control (seasoning only, C) and treatment I $(0.05\%\;Rosemary\;instead\;of\;liquid\;smoke,\;Tl)$. Two hrs of seasoning time was set, and 23 hrs of drying time was determined in all samples. Finally, T2 product was made by soaking treatments (three times of 1 sec, 8 sec and 1 sec) in $5\%$ (v/v) liquid smoke (Scansmoke PB 2110) after 30 min, 4 hrs and 22 hrs of hot-air drying, respectively. The histamine contents in 3 seasoned-dried products were in a 15.33-26.99 mg/l00g range. The water activities of 3 seasoned-dried products were 0.719-0.735 range, and the pH of T2 was lower than the others. In the comparison of POV and TBA values among products, the TBA values and POV of Tl and T2 were significantly low compared to C, and also the viable cell counts of T2 was relatively lower than those of the others. In the color values, significant changes were not found among products, and in the sensory evaluation for odor, taste and overall acceptance, T2 had relatively higher preference on the whole items.

• Korean Journal of Food Science and Technology
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• v.45 no.5
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• pp.613-618
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• 2013

The quality characteristics of brown rice polished with grains of four rice varieties (Hwaseonchal, Baegjinju, Ilpum and Goami) were examined. For the physical properties of native and fried brown rice starches, the gelatinization temperatures and enthalpies (determined with differential scanning calorimetry) of brown rice starches decreased with increasing amylose content. The pasting viscosities of native brown rice starches in distilled water were higher than those in $HgCl_2$ solution (as an ${\alpha}$-amylase inhibitor). The highest viscosity of gelatinized starch was observed for the starch of Ilpum rice variety relative to other varieties. Cystal packing arrangement of brown rice starches subjected to deep-fat frying converted A-type (typically observed for cereal starches) into V-type (formed by retrogradation and recrystllization of amylose molecules).

• Journal of the East Asian Society of Dietary Life
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• v.20 no.4
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• pp.560-566
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• 2010

In this study, the effects of the chilling process after thawing on pork quality were investigated by comparing the physiochemical properties and palatability of the samples just after thawing(0-TP) and the other chilled at $2^{\circ}C$ for two days after thawing (2-TP). The samples used for this study were obtained from vacuum packaged frozen loin from crossbred black pigs reared on Jeju island, and frozen at $-20^{\circ}C$ for 1 month and 12 months, and then thawing them at $4^{\circ}C$ for 20 hours. In the case of loin that was thawed after freezing for 1 month, 2-TP showed a higher water holding capacity and myofibril fragmentation index, lower hardness and chewiness, as well as better juiciness and palatability than 0-TP. However, effects of chilling after thawing were not significant in the case of loin that had been frozen for 12 months.