• Korean Journal of Agricultural Science
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• v.47 no.1
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• pp.67-81
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• 2020

The physicochemical parameters of honey are used to determine the botanic origin of honey and to specify the composition criteria for honey in regulations and standards. The parameters of honeydew and blossom honeys from Korean beekeepers were determined to investigate whether they complied with the composition criteria for honey in the food code legislated by Korean authority and to establish the parameters which should be subjected to principal component analysis for improved differentiation of honeys. The fructose and glucose contents of the honeydew honey did not comply with the composition criteria. The ash content of the honey was closely correlated with CIE a^* and CIE L^* The principal component analysis of fructose to glucose ratio, CIE a^*, CIE L^*, ash content, free acidity, and fructose and glucose contents enabled classification of honeydew, chestnut, multifloral, and acacia honeys. Additional advantage of the principal component analysis (PCA) is that the physicochemical parameters, such as fructose to glucose ratio (F/G) and color, can be determined using the analytical instruments for composition criteria and quality control of honey. This study suggested that composition criteria for honeydew honey should be established in the food code in accordance with international standards. The principal component analysis reported in this study resulted in improved classification of the honeys from Korean beekeepers.

• Food Science and Biotechnology
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• v.16 no.5
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• pp.663-674
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• 2007

Starches from different botanical sources differ in the ratio of amylose to amylopectin contents, molecular structures of amylose and amylopectin, granule morphology, and minor-component contents. These structural features result in different gelatinization, pasting, retrogradation properties, and enzyme digestibility of starch granules. In this review, compositions and molecular structures of starches and their effects on the physicochemical properties are summarized and discussed.

• Korean journal of food and cookery science
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• v.6 no.2
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• pp.37-50
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• 1990

The cause and the degree of the cis to trans isomerization were investigated about soybean oil (SBO), corngerm oil (CGO), cottonseed oil (CSO), margarine (MG) and shortening (ST). All samples treated with various conditions were analyzed to determine physicochemical characteristics (AV, POV, IV, RI), fatty acid composition, total trans fatty acid content and change of trans fatty acid composition by GLC, IR and HPLC. The results were obtained as follows; 1. Physicochemical constants were changed with a gentle slope according to incubating period at 40${\pm}$2$^{\circ}C$ and physicochemical constants of margarine and shortening were changed, significiantly. 2. The saturation degree in the unsaturated fatty acid composition determined by GLC gradually were increased during incubation and heating periodically. For palmitic-and stearic acid content at the samples stored in the incubator, the saturation degrees were gradually increased. But for the case of heat treatment, they were increased more rapidly than other fatty acids. 3. Total trans fatty acid contents in each samples were determined by GLC, IR and HPLC, the amount of trans fatty acids were measured with discrepancy. It was caused by deviation of analytical instruments, methods and the kinds of samples. Trans fatty acids were measured more definitly in IR more than GLC and HPLC. On the other hand, total trans fatty acid contents in average levels for SBO, CGO, CSO, MG and ST stored for 35 days and heated for 24 hours were 1.3%, 1.1%, 0.9%, 22.6% and 13.8%, and 3.6%, 3.0%, 2.8%, 41.2% and 20.8%, respectively.

• Food Science and Biotechnology
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• v.17 no.5
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• pp.1010-1015
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• 2008

The effects of heat treatment on the physicochemical properties and mineral composition of sun-dried salt were investigated. The salts parched at high temperature were appeared the higher alkalinity and the lower oxidation-reduction potential (ORP) than the samples without heat treatment. The commercial salts (bamboo salt and yellow loess salt) and the sun-dried salt parched at high temperature had relatively higher sodium ion content (418-450 ppm) compared to that (418.0 ppm) of refined salt. The increase of calcium ion occurred in the salts parched at high temperature compared to the sun-dried salt without heat treatment, but the magnesium ion was vice versa. The commercial salt, yellow loess salt had highest turbidity (0.973) whereas sun-dried salt showed lowest level (0.097) among the tested samples. Turbidity of heat treatment samples decreased as solubility increased. The maximum concentration of dialyzed salt was reached after 4 hr regardless of various processed salts, but those had no difference significantly among the tested samples. The X-ray diffraction patterns of the parched sun-dried salts showed different peak intensity with common salts, and they were similar to the patterns of oxide salts, especially MgO. The maximum value (2.56%) of MgO appeared in the sun-dried salt parched at $1,400^{\circ}C$.

• Journal of the Korean Society of Tobacco Science
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• v.17 no.1
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• pp.79-97
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• 1995

On the basis of the literature, which is at present still scientific information improvable, the results of research done so far into the occurrence and analytical methodology of major markers of environmental tobacco smoke(ETS) have been summarized. Key areas addressed are: differences in physicochemical composition between mainstream smoke, sidestream smoke and ETS: techniques for field measurement of ETS: relationship between indoor air quality with ETS and its distribution view of US EPA and its problems: biological effects and concerning estimation of ETS exposure.

• Journal of Animal Science and Technology
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• v.47 no.1
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• pp.91-98
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• 2005

Results of meat quality, physicochemical characteristics, fatty acid and amino acid composition of the Korean Native Black Pig(70 and 90 kg of slaughter weight; KNBP) versus Landrace(110kg of slaughter) are as below. Compared with Landrace, the KNBP exhibited a greater lean meat yield, with no difference in backfat thickness between Landrace and KNBP. There were no difference in chemical composition between Landrace and KNBP, but pH, and cooking loss in the KNBP were superior value than those of the Landrace. These results, KNBP were affected in sensory property and cooking yield. Amino acid content of KNBP and Landrace were significant differences between Landrace and KNBP. Except for the methionine, essential amino acid contents of KNBP had significantly higher than those of Landrace. In the change of fatty acid composition, the Landrace had significantly higher percentages of palmitic(l6: 0), stearic(18: 0) and linolenic(18: 3) acids than that of KNBP, but linoleic acid(l8: 2) was decreased.

• The Korean Journal of Food And Nutrition
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• v.29 no.5
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• pp.706-715
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• 2016

Nutritional composition and physicochemical properties changes in mustard leaf kimchi were investigated during fermentation of up to 3 months. The pH decreased, and the titratable acidity gradually increased according to increase of fermentation periods. Fructose and glucose were the major free sugars in mustard leaf kimchi, and their amounts were significantly decreased with fermentation periods (p<0.05). Lactic acid content showed a significant increase with maximum increase at 3 months. All types of kimchi contained 20 amino acids, but the content of most amino acid fluctuated during fermentation. Except for K and Zn, the content of other ingredients including Ca, Fe, Mg, Na, Se were the highest in kimchi fermented for 2 months. The unsaturated fatty acid of mustard leaf kimchi was higher than that of saturated fatty acid, and total fatty acid of kimchi significantly decreased after 2 months (p<0.05). Most vitamin contents showed a tendency to decrease with fermentation, in particular, vitamin B complex except for $B_2$ significantly decreased after 3 months (p<0.05). The results provide fundamental data for determining the appropriate fermentation period to improve the quality of kimchi.

• Applied Biological Chemistry
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• v.45 no.3
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• pp.134-137
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• 2002

Approximate composition and physicochemical properties of 2 cultivars of plum (P. salicina), Humoosa and Daeseok, were examined. The contents of crude fat and N-free extract were different between 2 cultivars. Total mineral contents of Humoosa and Daeseok were 30.00 and 17.99% respectively, and S, K and Mg were major minerals in both cultivars. Humoosa has higher contents of fructose whereas Daeseok has higher contents of sucrose. Major organic acid in flesh was malic acid. While citric acid was major organic acid in the peel of Humoosa, malic acid was major in the peel of Daeseok. Glutamic acid, alanine and ${\gamma}-aminoisobutyric$ acid were major free amino acid in both cultivars and their total contents were about the same.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.25 no.3
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• pp.294-300
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• 2015

Objectives: The aim of this study is to identify physicochemical properties such as chemical composition, size, shape and crystal structure of powder byproducts generated from a metallization process and its 1st scrubber in the semiconductor industry. Methods: Powder samples were collected from inner chambers during maintenance of the W-plug process equipment (using tungsten hexafluoride as a precursor material) and its 1st scrubber. The chemical composition, size and shape of the powder particles were determined by field emission scanning electron microscopy (SEM) and transmission electron microscopy (TEM) equipped with an energy dispersive spectroscope (EDS). The crystal structure of the powders was analyzed by X-ray diffraction (XRD). Results: From the SEM-EDS and TEM-EDS analyses, O and W were mainly detected, which indicates the powder byproducts are tungsten trioxide ($WO_3$), whereas Al, F and Ti were detected as low peaks. The powder particles were spherical and nearly spherical, and the particle size collected from the process equipment and its 1st scrubber showed 10-20 nm (agglomerates: 55-90 nm) and 16-20 nm (agglomerates: 80-120 nm) as primary particles, respectively. The XRD patterns of the yellow powder byproducts exhibit five peaks at $23.8^{\circ}$ $33.9^{\circ}$ $41.74^{\circ}$ $48.86^{\circ}$ and $54.78^{\circ}$ which correspond to the (200), (220), (222), (400), and (420) planes of cubic $WO_3$. Conclusions: We elucidated the physicochemical characteristics of the powder byproducts collected from W-plug process equipment and its 1st scrubber. This study should provide useful information for the development of alternative strategies to improve the working environment and workers' health.

• Human Ecology Research
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• v.60 no.2
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• pp.303-315
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• 2022

The physicochemical properties of traditional kochujang added with naked oat flours (0, 5, 10, 15%) were periodically examined during fermentation for 20 weeks at 25℃(± 2 ℃). The proximate composition of roasted naked oat flours were as follows: water 0.67%, ash 1.63%, fat 10.37%, protein 13.63%, carbohydrates 73.70%. The water contents of traditional kochujang added with naked oat flours decreased gradually according to the addition level. The pH of traditional kochujang added with naked oat flours increased according to the added level, whereas pH decreased gradually during fermentation. The acidity was opposite to pH. The L (lightness), a (redness) and b (yellowness)-values of samples increased according to the amount of added naked oat flours, whereas they decreased gradually during fermentation. The salinity and sweetness of samples decreased according to the amount of added naked oat flours. Amino acid composition of traditional kochujang added with naked oat flours was higher than that of the control during fermentation. Aspartic acid, alanine, leucine, and arginine were high in the case of traditional kochujang added with 0% naked oat flours, and aspartic acid, leucine, alanine, proline. And arginine were high in the case of traditional kochujang added with 15% naked oat flours. The dietary fiber content was 5.38g/100g in the case of 0% addition and 5.75g/100g in the case of 15% addition. As a result of the above results, it was found that the physicochemical properties of traditional kochujang added with naked oat flours could be improved, and the possibility of developing a traditional kochujang beneficial to health was confirmed.