• Korean Journal of Agricultural Science
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• v.14 no.2
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• pp.301-308
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• 1987

The results of experiment to find out the optimum pasteurization condition by heating from $50^{\circ}C$ to $70^{\circ}C$ at intervals of $5^{\circ}C$ and to review chemical composition, microbiological aspects and keeping quality were summarized as follows: 1. The milk sample pasteurized at $50-70^{\circ}C$ showed the decreased pH value from 6.55 to 6.42 while the contents of protein, fat, lactose and ash did not have significant changes. 2. Non-casein nitrogen and filterable nitrogen decreased while casein nitrogen and non protein nitrogen increased as the heat treatment increased. 3. The content of calcium and vitamin C decreased and artificial digestibility for the pasteruized milk increased from 14.07% to 20.00% by the heat treatment. 4. Milk pasteurized at $65^{\circ}C$ had viable bacteria counts $1.3{\times}10^4/m{\ell}$, coliforms negative, psychrotrophic bacteria $9.5{\times}10^2/m{\ell}$ and 99.0% pasteurization effect. 5. Milk pasteurized at $65^{\circ}C$ did not show significant changes in chemical composition and microbiological aspects at $4^{\circ}C$ in refrigerator.

• Applied Chemistry for Engineering
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• v.31 no.4
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• pp.443-451
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• 2020

In this study, the physico-chemical properties and pyrolysis kinetics of livestock mature solid fuel were investigated to know its feasibility as a fuel. Ultimate and proximate analysis results showed that livestock mature solid fuel has high contents of volatile matter (64.94%), carbon (44.35%), and hydrogen (5.54%). The low heating value of livestock mature solid fuel (3880 kcal/kg) was also higher than the standard requirement of solid fuel (3000 kcal/kg). Thermogravimetic analysis results indicated that livestock mature solid fuel has three decomposition temperature regions. The first temperature zone (130~330 ℃) was consisted with the vaporization of extracts and the decomposition of hemicellulose and cellulose. The second (330~480 ℃) and third (550~800 ℃) temperature regions were derived from the decomposition of lignin and additional decomposition of carbonaceous materials, respectively. The activation energy derived from model free kinetic analysis results including Friedman, Flynn-Wall-Ozawa (FWO), and Kissinger-Akahira-Sunose (KAS) methods for the pyrolysis of livestock mature solid fuel was in the range of 173.98 to 525.79 kJ/mol with a conversion rate of 0.1 to 0.9. In particular, the activation energy increased largely at the higher conversion than 0.6. The kinetic analysis using a curve-fitting method suggested that livestock mature solid fuel was decomposed via a multi-step reaction which can be divided into five decomposition steps.

• Journal of Conservation Science
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• v.24
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• pp.13-22
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• 2008

The identification of species, hygroscopic property, and ability of ethylene gas absorption of 23 ancient charcoals excavated from wooden coffin burials and roof-tile kilns of Chudong-ri cultural site were investigated. All of the 12 charcoals excavated from wooden coffin burials were broad-leaved trees. Among the total 12 samples, 9 samples were Lepidobalanus and others were Celtis spp.. On the other hand, other 11 charcoals from roof-tile kilns were needle-leaved tree, Pinus spp.(hard pine). The broad-leaved tree charcoals from wooden coffin burials showed a higher moisture absorption capacity than needle-leaved tree charcoals from roof-tile kilns. The ethylene gas absorption was greater in the Lepidobalanus charcoal than that of Celtis spp. and Pinus spp. (hard pine) charcoal. The broad-leaved tree charcoal having high absorption ability of substances was due to a large microporous and specific surface area. Therefore, it was estimated that broad-leaved tree charcoals were filled in order to make favorable condition in tomb. The wood quality of pine is soft and easy to burn because of low specific gravity, as well as high calorific value by resin in wood. We could assume that the pine wood was used as fuel for roof-tile kilns because of easy control of heating and thermal power.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.43 no.2
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• pp.93-99
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• 2010

This study was conducted to prepare canned salmon frame and to characterize its food components. In the preparation of high-quality canned foods, the boiling water generated in the pre-heating process should be removed, and then the pre-treated canned salmon frame should be sterilized for an $F_0$ value of 12 min. The proximate composition of the canned salmon frame prepared under optimal conditions (CSFP) was 58.4% moisture, 15.7% protein, 21.4% lipid, and 3.5% ash. Based on the results of volatile basic nitrogen and microbiological tests, the CSFP was acceptable. The sensory score for the color of CSFP was 4.1 points, which was higher than that of commercial canned salmon frame (CCSF). However, there were no significant differences in the sensory scores for flavor and taste between CSFP and CCSF. The total amino acid content of CSFP was 14.58 g/100 g, which was 4.9% lower than that of CCSF. The major amino acids in CSFP were aspartic acid (11.0%), glutamic acid (14.8%), and lysine (10.6%), which accounted for 36.4% of the total amino acid content. The CSFP was high in calcium and phosphorus, while it was low in magnesium and zinc. The major fatty acids in CSFP were 16:0 (15.2%), 18:1n-9 (17.0%), 18:2n-6 (16.7%), 20:5n-3 (9.3%), and 22:6n-3 (8.8%). Based on the results, CSFP is a high-quality canned food in terms of hygiene and nutrition.

• Journal of Life Science
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• v.29 no.12
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• pp.1358-1363
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• 2019

In this study, the effect on the free amino acid content and anti-oxidative activity of Arctium lappa samples by heat treatment were compared to obtain data on the conditions required for properly processing the root as a raw material for tea. The results of DPPH and ABTS radical scavenging activity assays showed that 180℃-4 min and 200℃-3 min treatments retained relatively high activity. All heat treatment conditions showed increased polyphenol content compared to the initial sample value of 42.72 mg/l, and the 180℃-4 min and 200-3 min treatments were higher than the others at 60.09 mg/l and 62.74 mg/l, respectively. In the free amino acid analysis of the A. lappa root tea, the tendency of the initial content was confirmed to decrease as temperature and time increased. Changes in phenylalanine, histidine, leucine, and isoleucine were found to be high, while aspartic acid and proline changes were relatively low. Overall, amino acid content decreased significantly under heating conditions above 180℃-3 min and 200℃-2 min. From these results, heat treatment of A. lappa root at 180℃-4 min was deemed optimal based on anti-oxidative activity and free amino acid content.

• Journal of the Korean Wood Science and Technology
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• v.38 no.1
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• pp.17-26
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• 2010

Recently, yellow poplar (Liriodendron tulipifera L.) is getting attention in Korea due to the fast growing and high yield and quality of lumber. But, it is thought that the color difference between heartwood and sapwood may restrict the practical use of it. This study was aimed to enhance the value of yellow poplar lumber by the color control using high temperature heat-treatment, which had been tried for domestic cedar (Kim et al., 2009). The material properties including surface color of yellow poplar lumber were evaluated according to heat treatment conditions. The difference of color between sapwood and heartwood could be reduced by heat treatment at a temperature about $200^{\circ}C$. Long heating time was more effective in reducing the difference. The Equilibrium Moisture Content (EMC) of heat-treated wood was as low as 50 percent of the control. The result obviously indicates that heat-treated wood is more dimensionally stable in the change of moisture condition. The durability against wood rotting fungi also increased by the heat-treated, but it was not so effective as the case of cedar. The changes of mechanical properties of heat-treated yellow poplar were very similar to that of heat-treated cedar. In order to develop new use of heat-treated yellow poplar, the changes of mechanical properties should be considered. There were no significant changes in microscopic structure which may cause changes in mechanical properties. Further study of heat-treated wood is needed to scrutinize the causes of changes of material properties.

• Journal of Korean Home Economics Education Association
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• v.3 no.1
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• pp.1-13
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• 1991

The purpose of this study is to find out problems through looking into the actual condition of management and the extent of application in cooking practice in High School Home Economics Education, and as a practical subject, to present some basic materials to contribute to accomplishing the object of High School Home Economics Education through trying to find a direction to enhance educational value. The contents of this study are these ： to study with a theoretical background character, object, and contents of Home Economics referring to related books and to investigate the actual condition of management, the extent of application to life of cooking practice unit, and standard of recognition of students and teachers about this subject and to find out rational and efficient method of management. 552 girl students and 72 home economics teachers in cities and counties in Kangwon-do were asked to answer the answer-sheet prepared. The result of this study is summerized as follows. 1. Most of the respondent regard the characters and objects of Home Economics as a matter of basic education, education for life, and education for the wholeman, but they neglect the aspect of education for a course of this subject. 2. Among the contents of Home Economics, students are much interested in the Unit of preparing table, especially in cooking. Most of the teachers teach the cooking unit with only explanation without practice because of the lack of material and human resources. 3. Students have desire to do cooking practice, but the extent of application of their real life appears to be low. 4. It appears to be necessary that boy students as well as girl students should learn Home Economics as an education for preparation for managing housework. 5. Home Economics teachers are mostly satisfied with their teaching profession. But teachers who have been teaching for 3 or 5 years appear not to be satisfied with it. 6. Although Home Economics teachers can teach Cooking practice Unit with confidence, they usually do it with theory rater than with practice, and they evaluate it after practicing, but most of them do not add the result to the student’s grade. 7. They use most of the cookers fixed on the standard list of High School Cooking Practice appliances, but they seldom use electric heating cookers.

• Applied Chemistry for Engineering
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• v.22 no.4
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• pp.429-432
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• 2011

The feasibility of applications of the char obtained from a gasification process of municipal-waste refuse derived fuel (RDF) as an auxiliary fuel was evaluated by combustion experiments. The higher heating value of the RDF char was 3000~4000 kcal/kg and its chlorine content was below the standard requirement demonstrating its potential as an auxiliary fuel. In the combustion exhaust gas, the maximum $NO_x$ and $SO_2$ concentrations were 240 ppm and 223 ppm, respectively. If an aftertreatment is applied, it is possible to control their concentrations low enough to meet the air pollutant emission standard. The HCl concentration was relatively high indicating that a care should be taken for HCl emission from the combustion of RDF. Based on the temperature distribution within the reactor, the concentration change of $O_2$ and $CO_2$, and the amount and the loss on ignition of solid residue, it was inferred that the combustion reaction was the most reliable when the excess air ratio of 1.3 was used.

• Journal of the Korean Society of Food Science and Nutrition
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• v.12 no.1
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• pp.7-11
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• 1983

The purpose of this study was to prepare low methoxyl pectins (LMPs) by pectinesterase (PE) using waste tangerine peels and to compare the chemical, physical and gelling properties of the prepared pectins with the commercial LMP. The LMPs were prepared by treating albedo with 0.25M $Na_2CO_3$ to activate the PE. PE was then inactivated by heating. The sample was centrifuged and the supernatant was collected. LMP was obtained as precipitate by adding alcohol to the collected supernatant. The amounts of extractible pectins in albedo were 12.71~12.98% on a dry weight basis. Methoxyl contents of LMPs prepared by treating albedo with PE at pH 7.5 for 10min, at pH 8.5 for 10min, 20min and 30min were 5.12%, 4.27%, 3.08%, 1.85% respectively, demonstrating that the methoxyl contents of the preparations decreased as the degree of treatment albedo with PE increased. The acetyl contents of the preparations ranged from 0.09% to 0.12%, the values of which do not interfere with gel formation. The anhydrouronic acid contents of the prepared pectins were in the range of 94.2%~94.8%. The values of viscosity and molecular weights of the prepared LMPs tent to decrease as the degree of PE action on albedo increased. The textural value of the prepared LMP gels determined by Consistometer, Ridgelimeter and Instron denonstrated that the excess treatment of albedo with PE significantly impaired the gelling properties of the preparations.

• Journal of Nutrition and Health
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• v.18 no.2
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• pp.126-138
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• 1985

A study was made on the effect of anti-nutritional factors found in some Korean beans : soybean, red bead, mung bean and kidney bean. Two animal experiments were conducted to investigate the nutritional value of the beans. The first experiment, in which the diet contained 15% protein from raw beans, compared the intensity of inhibition caused by methionine deficiency or a total amino acid deficiency. In the second experiment, the conditions were the same as in experiment I, except that heated beans were substituted for raw beans. Severe growth inhibition and high mortality was found in the raw kidney bean and red bean groups than in the soybean and mung bean groups. As no effect on the growth inhibition of raw bean groups was shown by methionine and protein supplementation, the inhibition could be ascribed mainly to the low feed intake and the low protein digestibility caused by toxic factors. Pancreatic enlargement was obserbed in all the raw bean groups. A increase in body weight, a decrease in mortality and a decrease in the weight pancreases were found in the heated bean groups. But the digestility of the diet and of the protein and the PER by heating did not increase as markedly as weight, except in the heated red bean groups. Even with heat treatment, the whole inhibitory action could not be eliminated.