• Food Science and Preservation
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• v.10 no.3
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• pp.345-359
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• 2003

This study was conducted to investigate the fermentation characteristics of kimchi treated with different methods of water extracts of powdered green tea(GT). Four different kimchis, the SB-kimchi(control) which was not treatment of the extracts, SG-kimchi prepared with Chinese cabbage(CC) salted in 1％ GT containing 10％ brine, DG-kimchi prepared with CC dipped in 1％ GT for 30 min after salting, MS-kimchi prepared with the salted CC mixed with 1％ GT containing seasonings. All kimchis was fermented at 10$^{\circ}C$. The pH of treated-kimchis were maintained higher than those of control products during fermentation, but it showed no big difference between each treated groups. Total microbe of SB-kimchi(6.27-9.37 cfu/mL) was higher than those of GT-treated kimchi(5.17-9.20) during fermentation. The ratio of lactic acid bacteria against total microbe was higher than the treated kimchis. Total polyphenol content of kimchi was 52.75 mg％ in DG-kimchi, 47.71 mg％ in MS-kimchi, 44.89 mg％ in SG-kimchi, 30.70 mg％ in SB-kimchi on the 5th days of fermentation. Scores of crispy taste of SG- and DG-kimchi on the 5th days of fermentation was 4.03 and 4.01 points, respectively which was higher than control products. Scores of fishy and hot taste of GT-treated kimchi were lower than those of control products during all fermentation periods.

• Resources Recycling
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• v.26 no.5
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• pp.39-47
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• 2017

In this study, the precipitation of rare earth-sodium sulfate with sodium sulfate was conducted in order to separate rare earth from Fe in rare earth sulfate solution. Neodymium (Nd) was easily precipitated as Nd-sulfate salt with sodium sulfate, on the other hand, excessive sodium sulfate was needed for the precipitation of Dy-sulfate salt. Also neodymium not only promoted the precipitation of dysprosium sulfate salt but also increased recovery of dysprosium sulfate salt in sulfuric acid solution. At the condition of $60^{\circ}C$ precipitation temperature, 3 h reaction time, 7 equivalents sodium sulfate, the recovery of neodymium and dysprosium sulfate salt was 99.7% and 94.3% respectively from the sulfuric acid solution containing Nd of 23.39 mg/ml and Dy of 8.67 mg/ml. Lastly, from the results of separation of Dy to Nd by the method of sulfate double salt, the effect of salting out with NaCl is important to increase the grade of Dy, and 98.7% of Dy grade could be obtained in this study.

• The Korean Journal of Pesticide Science
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• v.18 no.4
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• pp.296-313
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• 2014

A QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) multiresidue method was developed for the simultaneous analysis of 124 pesticides in soil by LC-MS. The procedure involved liquid extraction of soil immersed with 0.2N $NH_4Cl$ by acetonitrile with 1% acetic acid, followed by anhydrous $MgSO_4$ and sodium acetate, and dispersive SPE cleanup with $MgSO_4$, primary secondary amine (PSA) and $C_{18}$. The extracts were analyzed with LC-MS/MS in ESI positive mode. Standard calibration curves were made by matrix matched standards and their correlation coefficients were higher than 0.99. Recovery studies for the validation were carried out using two type soils, loam and sandy loam, at four concentration levels (0.005, 0.01, 0.02, and 0.1 mg/kg). The recoveries of pesticides were in the range of 70-120% with < 20% RSD except 4 pesticides, Benfuracarb, Ethiofencarb, Pymetrozine, and Pyrethrin. This result indicated that the method using QuEChERS and LC-MS/MS could be applied for the simultaneous determination of pesticide residues in soils.

• Korean Journal of Soil Science and Fertilizer
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• v.42 no.3
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• pp.179-186
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• 2009

Relation between soil salinity and forage yield of five upland crops such as sudan grass, sesbania, barnyard grass, corn and soybean was studied in the three reclaimed lands of Korea during two years from 2007 to 2008. Although plant number emerged was obtained satisfactory by desalting treatment, further growth of crops was sharply affected by re-salting process according to soil drying. Soil salinity varied place by place and changed constantly, crop growth was differently responded to soil salinity according to the specific conditions of the reclaimed lands. In the Iweon reclaimed land with higher soil water conductivity and sandy soil texture, crop growth and yield sharply decrease with increase of soil salinity. Relation between soil salinity and crop growth and yield was well expressed as logarithmic function. Surface soil EC to reach at 50% of growth reduction to the tallest height of crops was $5dS\;m^{-1}$ for soybean, $6dS\;m^{-1}$ for corn and $7dS\;m^{-1}$ for sudan grass, sesbania, and barnyard grass by logarithmic function. In the Hwaong and Yeongsangang reclaimed lands with low soil conductivity and finer soil texture, plant growth response to salt stress was statistically vague by mixing of harmful influence from flooding and wet injury. However, it is observed that crop growth and yield on the place of lower salinity was better than crop growth on the place of higher salinity. It is accordingly concluded that flooding control during summer rainy season is vary important as well as desalting process for good growth of soiling and forage crops in the newly reclaimed land from tidal flat.

• Journal of Aquaculture
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• v.6 no.2
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• pp.71-87
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• 1993

Two forms of sea mustard, Undaria Pinnatifida were cultured in order to compare the morphological characteristics and the efficiency of production. U. Pinnatifida f. distans was collected from Wando, Korea and U. Pinnatifida f. typica was transplanted from Sanriku, Japan. The latter form grew faster in length and weight than the former. Maximum growth was shown in early April for both forms, and the growth rates decreased after this. Absolute growth rates between the two forms were quite different. Average total lengths at the harvest season was 161.1cm in U. Pinnatifida f. distans and 183.5 em in U. Pinnatifida f. typica and average weights of those two forms were 1,003.4g and 1,314.6g, respectively. The weight of available parts for the salting process of the two forms were 734.8g and 968.5g, respectively. The rates of total length versus the length of the available part of the two forms were $76\%$ and $83\%$, respectively and those of the total length versus weight of the available part of them were $43.8\%$ and $52.7\%$, respectively. The results of this study suggest that the U. pinnatifida f. typica had more available part per unit weight than that of the U. pinnatifida f. distans for the efficiency of salt processing.

• Journal of the Korean Society of Food Science and Nutrition
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• v.12 no.2
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• pp.66-72
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• 1983

In order to improve the quality of salted sea mustard, the conditions of blanching, salting, and storage were examined. The process in which sea mustard was blanched for 20 seconds in boiling seawater, soaked in saturated brine solution for 20 hours and then salted for 10 hours by the spreading 10~20% (w/w) of granulated dry salt to obtain the moisture content of about 60% or below, resulted a good color retention of chlorophyll and carotenoid pigments, and organoleptic quality. The shelf-life of the product estimated by 30-40% pigment retention was 50-60days when stored at $4^{\circ}C$ or below.

• Korean Journal of Soil Science and Fertilizer
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• v.42 no.5
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• pp.355-363
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• 2009

Double cropping system of oilseed crops introduced rape and castor bean was studied in the newly reclaimed tidal land of Korea. Surface soil EC to reach at 50% of growth reduction to the tallest height of crops was estimated $4dS\;m^{-1}$ for castor bean and $6dS\;m^{-1}$ for rape by logarithmic function. The castor bean cultivated during rainy summer much more suffered serious growth and yield reduction by flooding damage in the Hwaong and Yeonsangang reclaimed lands having low soil conductivity and finer textured soil than in the Iweon reclaimed land having higher soil conductivity and coarse sandy textured soil. Rape cultivated during dry winter-spring much more suffered serious growth and yield reduction by high soil salinity come from re-salting process. 50% yield reduction was estimated at $2.0\;2.5dS\;m^{-1}$ of surface soil EC by logarithmic function. Consequentially, it was concluded that oilseed production for energy by double cropping system of rape and castor bean might be possible under good controling soil salinity below $4dS\;m^{-1}$ for castor and $3dS\;m^{-1}$ for rape in the newly reclaimed land of Korea.

• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.2
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• pp.240-248
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• 1996

To clarify the potentiality of sea cucumbers as dietary food, the effects of those glycoprotein on dietary proteins and physicochemical properties of those proteins were studied. Crude glycoprotein was efficiently extracted using 20mM sodium phosphate beffer(pH 7.0) and by salting out with 80% ammoniym sulfate saturation. The fractions obtained through the DEAE-cellulose ion exchange chromatography was identified as glycoprotein by Schiff's reagent and SDS polyacrylanide gel electro-phoresis. The yields of each glycoprotein from the three kinds of sea cucumbers were 0.814(red), 0.184(blue) and 0.232(black) and the molecular weights of the glycoproteins subunits were ranged from 20,000 dalton(blue and black) to 29,000 dalton(red), respectively. The electrophoretic patterns of the glycoprotein isolates were similar to each other and any significant difference in amino acid pattern was observed. Predominant arnino scids were Asx(aspartic acid and asparagine) and Glx(glutamic acid and glutamine) ; in contrast, histidine and methionine were below 2% as compared to total amino acids. water holding capacities of the glycoprotein isolates from red, blue and black cucumbers were equally 100% and emulsion activities ranged from 53% to 64%. In addition the emulsion stabilities were 7.04, 1.37 and 2.44, respectively. In vitro digestibility of some proteins(casein, SPI and squid) was decreased as increasing the level of the freeze dried sea cucumber powder and glycoprotein isolates. But squid protein was not affected.

• Food Science and Preservation
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• v.13 no.2
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• pp.259-268
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• 2006

We investigated food preservation hurdles used for Korean traditional side dishes. As a first step of the research preparation and cooking recipes of the side dishes were surveyed, which are commonly used in Korean households. As next step, compositional and microbial quality attributes were measured onto the samples collected from the market. Antimicrobial ingredient added in the preparation are reasoned to work as important hurdles based on the scientific principles. Heating processes such as blanching, boiling, braising, hard-boiling and frying help to keep the produce decontamination or water activity adjustment. Measured salt contents of most side dishes were in the range of 1-5% with those of salt-preserved vegetables being higher. pH values were 4.7-6.4 with those of salt-preserved vegetables being lower and those of hard boiled fishes being higher. Soluble solids of braised or hard-boiled dishes were usually above $40^{\circ}Brix$, while those of blanched and seasoned vegetables had lower values. Water activity values were 0.93-0.95 for seasoned vegetables and 0.77-0.88 for hard-boiled or semi dried beans and seafoods. Product with processing steps of braising or blanching showed lower bacterial load of 102-104 cfu/g, while seasoned or salt-preserved vegetables and seafoods had aerobic bacterial count above 106 cfu/g. Korean traditional side dishes were found to apply the appropriate combinations of heating preparation process, water activity and pH adjustment and salting, providing the required preservation properties.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.4
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• pp.615-620
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• 2013

To extend the shelf-life of salted Chinese cabbages, electrolyzed water (EW) was used to wash raw Chinese cabbages before the salting process (to control microbial growth), and different storage temperatures evaluated (0, 4, and $10^{\circ}C$). A tap water washing group (TW) was used for comparison. The initial total bacterial population was 5.36 log CFU/g in the TW treatment and 3.50 log CFU/g in the EW treatment. The EW treatment decreased bacterial numbers by approximately 2 log CFU/g compared to the TW treatment and kept this initial population number for 32 days at $0^{\circ}C$. The salinity had no difference during storage. In general, several factors (pH, reducing sugars, hardness, and transmittance) decreased over time, and decreased slowly with EW treatment and $0^{\circ}C$ storage. Overall, the salted Chinese cabbages with EW treatment showed lower bacterial populations compared to TW treatment, and when stored at $0^{\circ}C$, delayed decreases in quality.