• Resources Recycling
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• 제20권3호
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• pp.48-54
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• 2011

Sulphuric acid leaching was conducted to extract the metal values from spent refinery catalyst. More than 95% of Ni and V and 30% of Mo could be leached out in 1 M sulphuric acid and 1 hr of leaching time. The decrease in Mo leaching was due to typical characteristic of Mo matrix. The activation energies of the leaching reactions showed the dissolution process follows a diffusion control mechanism. In order to leach out all Mo, further the leaching experiments were conducted with sulfur free spent refinery catalyst. For sulfur free spent refinery catalyst, a two step process of leaching with 1 M sulphuric acid followed by sodium carbonate washing showed better leaching than a two step leaching process with sodium carbonate followed by sulphuric acid washing, with almost 99% leaching of Ni, Mo and V. Solvent extraction using LIX 841 were conducted for a leach liquor containing Ni, 2 g/L; V, 9 g/L, Mo, 0.6 g/L. More than 98% of Mo was extracted from the leach liquor at A:O ratio of 5:2 in a 2 stage process. Similarly V was extracted at A:O ratio of 5:3 in a 2 stage process with 82% of total V extraction.

• Journal of the Korea Academia-Industrial cooperation Society
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• 제12권11호
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• pp.4924-4931
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• 2011

This research performed to evaluate a production processes reporting by the HACCP system of green vegetable juice products, containing lactic acid bacteria, stage of processing raw materials agricultural products and production facilities of general bacteria and pathogenic micro organism. General bacteria are found from four samples of storage of agricultural products at process stage and water was detected 8.67~14.67 CFU/ml. However, all samples were detected less than 105 CFU/ml as a legal standards after the process of UV sterilization. For the outcome of experiment of E.coli, E.coli O157:H7, B.cereus, L.moonocytogenes, Salmonella spp, Staph.aureus as the food poisoning bacterial, E.coli was detected until UV pre-step process in storage process and B.cereus was detected partly till 1st washing. Since all bacterial, Yeast and Mold are detected in main materials, pre-control method is a necessary to establish for decreasing with a number of initial bacteria of main materials and it is considered to establish the effective ways of washing and sterilization such as production facilities for cross contamination prevention of bacteria and Sthaphylococcus. Based on above results, the process of UV sterilization should be managed with CCP as an important process to reduce or eliminate the general and food poisoning bacterial of green vegetable juice products, including lactic acid bacteria. Therefore, it is considered to need an exhaustive HACCP plan such as control manual of UV sterilization, solution method, verification, education and training and record management.

• Korean Journal of Fisheries and Aquatic Sciences
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• 제49권6호
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• pp.772-778
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• 2016

To develop a value-added product from individually quick-frozen oysters Crassostrea gigas (IQFO), we prepared a retort pouched oyster soup (RPOS) from IQFOs and characterized its processing conditions and quality metrics. We found that the most appropriate manufacturing process for the RPOS consisted of half-thawing and washing raw IQF oysters, blanching, adding them to the retort pouch along with other ingredients (base soup stock, IQF oyster extract, radish, bean sprouts, garlic, and red pepper), sealing, retort sterilization ($120^{\circ}$, F0-value 10 min.), cooling, and packaging inspection. The moisture, crude protein, pH and salinity of the RPOS were 91.0%, 2.8%, 6.20 and 0.9%, respectively. The total amino acid content of the RPOS was 2,163.8 mg/100 g, and the main amino acids were glutamic acid, aspartic acid, leucine, proline, lysine and arginine. The primary inorganic ions were Na, K, S and Zn. In taste compounds, total free amino acid content was 313.4 mg/100 g, and the main free amino acids were glutamic acid, taurine, proline, hydroxyproline, aspartic acid, glycine, alanine, valine, lysine and arginine. This RPOS has good storage stability and organoleptic qualities compared with commercial retort pouched shellfish soup, and is suitable for commercialization as a value-added instant seafood soup.

• Korean Journal of Food Science and Technology
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• 제37권1호
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• pp.129-133
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• 2005

Aqueous chlorine dioxide and citric acid treatment was introduced to insure microbial safety of minimally processed and refrigerated (MPR) salad. Salad samples were treated with 50 ppm chlorine dioxide and 1% citric acid. Chemical treatment decreased total aerobic bacteria, yeast and molds, E. coli, and Listeria by 3.75, 3.47, 3.41, and 3.38 log cycles, respectively, and polyphenoloxidase activity of MPR salad by 49.73%. Plain water washing of salads did not effectively decrease microbial growth. These results indicate appropriate chemical treatment provides microbial safety and quality control in MPR salad during marketing.

• Journal of the Korean Society of Food Science and Nutrition
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• 제30권4호
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• pp.569-573
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• 2001

A pectic substance from citron peel was extracted with different methods to establish the optimum extraction conditions. The extraction yields of pectin with HCl, citrate and tartrate (concentration : 0.1 N, extraction ratio : 1 : 20) were 17.9%, 15.6% and 11.4%, respectively. Six times of 65% ethanol washing step was followed after first ethanol precipitation of acid extract for pure pectin. The degree of esterification (DE) of pectins was in the range of 43.0~47.6% and intrinsic viscosity was in the range of 0.94~2.63 (η$_{sp}$ /C (dL/g)). The sugar compositions such as rhamnose, xylose, glucuronic acid, galacturonic acid, galactose and glucose were little different in three kinds of pectins except for the content of arabinose.

• Journal of the Korean Society of Food Science and Nutrition
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• 제40권12호
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• pp.1743-1749
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• 2011

The microbial reduction and quality characteristics of salted Chinese cabbage using electrolyzed water were investigated. The electrolyzed water was used to control the microbes in the processes of primary washing, salting, and secondary washing. The total bacteria, lactic acid bacteria, coliform, pH, salinity, vitamin C, and total sugar were analyzed. After primary washing by electrolyzed water, the total bacteria populations were reduced to 2.78 log cfu/g, and the coliform populations were similarly reduced. After secondary washing by electrolyzed water, the total bacteria population of Chinese cabbage was reduced to a maximum of 1.5 log cfu/g. The salinity of Chinese cabbage and salting solutions increased rapidly over three hours, and then increased slowly. The sterilization effect of electrolyzed salting water could not last beyond 3 hours, because the OHCl concentration of electrolyzed water was reduced by over 90% at the third hours of the salting process. Vitamin C was reduced and total sugar did not change regardless of treatments during the salting process. Consequently, electrolyzed water was effective to remove microbes from salted Chinese cabbages.

• Journal of Food Hygiene and Safety
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• 제30권1호
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• pp.74-80
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• 2015

In this study, the microbial control effect after treatment of washing solutions (tap water, electrolyzed water, chlorine dioxide solution) and quality changes were investigated when Kwamegi is produced by means of the cold air drying. The initial moisture rate of the sample was 56.62% before drying. At the beginning of drying period, moisture rate sharply fell down but as the experiment progressed, moisture reducing rate was smoothly decreased. The color difference of Kwamegi before drying was 42.40, but it was reduced depending on the increment of drying temperature and time. TBA value of the initial sample was 0.219, rancidity were increased continuously when drying progressed. Total amino acid content was showed the highest value at $25^{\circ}C$ for 36h and the lowest at $40^{\circ}C$ for 12h. From the fatty acids analysis, major fatty acids were consisted of the 14:0, 16:0 and 18:1 (18.1520.96%, 28.0632.51% and 17.0619.81%, respectively). The microbial control effect was biggest when Kwamegi was washed with chlorine dioxide 100ppm for 60s. The microbe of the Kwamegi, Pseudomonas sp. and Pseudomonas putida were identified.

• Microbiology and Biotechnology Letters
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• 제35권2호
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• pp.135-141
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• 2007

To increase the consumer acceptability of yam and the shelf-life of fresh-cut yam, organic acid-treated fresh-cut yam was prepared. When uncontaminated fresh-cut yam was stored at $4^{\circ}C$ for 14 days after treatment with 1% (v/w) organic acids, the browning and microbial putrefaction of fresh-cut yam were inhibited by treatment of acetic acid or maleic acid, whereas treatment of citric acid and ascorbic acid, commonly used browning inhibitors in food industry, did not show apparent effects on the browning and putrefaction of yam. The Inhibitory effects of acetic acid or maleic acid were superior than those of NaOCl (100 ppm), hydrogen peroxide (100 ppm) or commercially available washing solution. Also, treatments of 1% acetic acid, or 1% maleic acid Into artificially-contaminated yam $(10^5\;CFU/g-yam)$ showed strong inhibition of browning and putrefaction during long term storage at $4^{\circ}C$. The growth inhibition test indicated that 0.1% is enough to inhibit the growth of psychrotrophic yam-putrefactive Pseudomonas sp., and treatment of 0.1% acetic acid, or 0.1% maleic acid inhibited the browning and microbial putrefaction of fresh-cut yam. Our results suggested long-term distribution of yam or other root crops products is possible by treatment of organic acid, such as acetic acid, combined with aseptic vacuum packaging technology.

• Journal of the Korean Wood Science and Technology
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• 제38권4호
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• pp.359-374
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• 2010

This study was carried out to investigate the chemotaxonomical correlation and chemical constituents of domestic Quercus spp. barks. The barks of Q. mongolica, Q. aliena, Q. serrata, Q. acutissima, Q. dentata, and Q. variabilis were collected in the experimental forest of Kangwon National University. The combined extracts were successively fractionated with n-hexane, methylene chloride and ethyl acetate using a separation funnel. A portion of the ethyl acetate and H2O soluble materials of each species were chromatographed on a Sephadex LH-20 column using various aqueous MeOH and EtOH-hexane as washing solvents. Spectrometric analysis such as NMR and MS, including TLC, were performed to characterize the structures of the isolated compounds. Ellagic acid (0.03 g), (+)-catechin (4.59 g), taxifolin (3.35 g), and glucodistylin (20.52 g) were isolated from Q. mongolica bark. Gallic acid (0.18 g), (+)-catechin (8.52 g), (+)-gallocatechin (0.09 g), taxifolin (0.54 g), and glucodistylin (3.28 g) were characterized from Q. acutissima bark. Gallic acid (0.38 g), ellagic acid (0.11 g), (+)-catechin (2.01 g), (+)-gallocatechin (0.12 g), and glucodistylin (0.39 g) were identified from Q. dentata bark. Ellagic acid (1.51 g), (+)-catechin (21.91 g), and glucodistylin (3.91 g) were purified from Q. aliena bark. Ellagic acid (0.84 g), (+)-catechin (0.82 g), taxifolin (4.02 g), and glucodistylin (21.50) were isolated from Q. serrata bark. Gallic acid (0.24 g), caffeic acid (0.05 g), (+)-catechin (0.32 g), and glucodistylin (0.65 g) were purified from Q. variabilis bark. (+)-Catechin and glucodistylin were isolated from all the barks. Glucodistylin can be a taxonomic index on Quercus spp.

• Korean Journal of Fisheries and Aquatic Sciences
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• 제54권1호
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• pp.1-8
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• 2021

In order to develop value-added low-salt fermented seafood with a long shelf-life, we prepared seasoned low-salt fermented Mideoduck (Styela clava) supplemented with fermentation alcohol (SME). The SME was produced by washing and dewatering shelled Mideoduck, followed by cutting and salting for 24 h at 0℃. The salted Mideoduck was seasoned and fermented with ingredients, including garlic, ginger, monosodium glutamate, red pepper, sesame, sorbitol and sugar, for 7-8 days at 0℃. After adding 3-5% fermentation alcohol, the Mideoduck was packed in a polyester container. The salinity, volatile basic nitrogen, and amino nitrogen content of the SME was 4.5%, 20.9 mg/100 g and 92.0 mg/100 g, respectively. In comparison with the control, the addition of 3-5% fermentation alcohol showed inhibitory effects of decreased freshness, texture degradation, and growth of residual bacteria. Additionally, the SME had good storage stability and organoleptic qualities when stored at 4±1℃ for 40 days. Therefore, it is suitable for commercialization as a seasoned low-salt fermented product with a long shelf-life. The total amino acid content of the SME was 11,774.5 mg/100 g, majorly comprising glutamic acid, aspartic acid, lysine, arginine, and leucine, and the free amino acid content was 506.4 mg/100 g, majorly comprising hydroxyproline, taurine, and glutamic acid.