• Economic and Environmental Geology
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• v.38 no.3 s.172
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• pp.207-219
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• 2005

The physical and chemical characteristics of soils in a small watershed were investigated and the effect of geology and land use on soil quality were examined by using multivariate statistical methods, principal components analysis and discriminant analysis. The soil developed from andesite had finer texture and higher contents of water extractable inorganic components, clay, and mafic minerals than the soil developed from granite. It is considered that the accumulation of salts in the farmland soils indicated by electrical conductivity, contents of cations and anions and pH was caused by fertilizer input during cultivation. The low contents of organic matter in the farmland soils was due to the enhanced oxidation of organic matter by tillage and by the harvest of crops. The contents of inorganic components are increased as following order: upland > orchard > paddy field > forest. The high contents of water soluble $SO_4\;^{2-}$ of paddy soils is due to the oxidation of sulfides mineral formed during the flooding period during the air-dry and extraction. The results of principal components analysis show the difference of soil quality was controlled by geology and land use. PCI indicate the input of fertilizer, mineral weathering and ion exchange reaction by application of nitrogenous fertilizers. The results of two discriminant analyses using water extractable inorganic components and their ratios by land use were also clearly classified by discriminant function 1 and 2. In discriminant analysis by components, discriminant function 1 indicated the effect of fertilizer application and increased as following order: upland > orchard > paddy field > forest soil. The investigated and predicted data for land use from discriminant analysis showed similar results. The discriminant analysis can be used as a useful method certifying the change of land use.

• Applied Biological Chemistry
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• v.44 no.4
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• pp.224-229
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• 2001

This study was carried out to examine the quality stability of powdered soup using powder from oyster wash water (PSW). To compare the quality stability, powdered soup from oyster hot-water extracts (PSE) was also prepared by mixing hot-water extract powder (15 g), table salt (5 g), cream powder (19 g), milk replacer (12 g), wheat flour (20 g), corn flour (15 g), starch (5 g), glucose (7.5 g), and onion powder (1.5 g). In preparing PSW, powder from oyster wash water, instead of powder from oyster hot-water extracts, was added and other additives were the same proportion as PSE. The PSW and PSE were packed with laminated film bag (OPP,$20\;{\mu}m$; PE, $20{\mu}m$; paper, $45\;g/m^3$; PE, $20\;{\mu}m$; Al, $7\;{\mu}m$; PE, $20\;{\mu}m$), and then stored at ambient temperature for 12 months. The moisture content, water activity, peroxide value, and fatty acid composition showed little changes during storage of the PSW, The pH, volatile basic nitrogen content, and brown pigment formation increased slightly, while white index decreased slightly during storage of PSW. No significant difference was observed in the changes of food components between PSW and PSE during storage. According to a sensory evaluation, the change in quality of PSW was negligible during 12 months of storage. From the results of the chemical experiment and sensory evaluation, PSW packed with laminated film bag (OPP, $20\;{\mu}m$; PE, $20\;{\mu}m$; paper, $45\;g/{\mu}m$; PE, $20\;{\mu}m$) was revealed to be preserved in good quality during 12 months of storage.

• Food Science and Preservation
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• v.24 no.7
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• pp.923-933
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• 2017

This study was carried out to examine the quality characteristics of Doenjang manufactured with or without soaking Meju in brine according to salt concentrations (8 and 12%) during fermentation for 6 months. The moisture content and salinity of Doenjang fermented for 6 months were 54.9-60.3% and 7.8-12.5%, respectively. Doenjang using soaking Meju in brine had higher pH and lower titratable acidity than that using non-soaking Meju. The reducing sugar content in all samples was increased until 2 months and then decreased regardless of soaking Meju, especially that of non-soaking 8% Doenjang was the highest. The 8% low-salt Doenjang was shown the highest amino-type nitrogen content, especially the soaking Doenjang was higher than the non-soaking Doenjang. ${\alpha}$-amylase activity of all samples during fermentation were continuously decreased from 0.91-0.94 Unit/g to 0.01-0.06 Unit/g, especially the 8% soaking Doenjang was shown the highest activity after 2 months. Total bacterial count of the soaking Doenjang at the 6 months was in range of 7.8-8.0 log CFU/g and that of the non-soaking Doenjang was in range of 7.2-7.5 log CFU/g. By taste analysis, the 8% soaking Doenjang was shown the similar taste pattern with commercial Doenjang. In conclusion, the 8% low-salt Doenjang manufactured with soaking Meju in brine was a suitable concentration in order to reduce salt intake.

• Food Science and Preservation
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• v.24 no.2
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• pp.230-236
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• 2017

This study was carried out to investigate the effects of ultrasonic thawing on physicochemical characteristics of frozen pork sirloin. To determine the velocity of an ultrasonic thawing machine, $-80^{\circ}C$ frozen pork sirloins were thawed using 132, 580, and 1,000 kHz ultrasonic thawing machines, and the physicochemical properties of pork sirloin thawed with $15^{\circ}C$ tap water and those using the ultrasonic thawing machines were compared. As a result, thawing speed by ultrasonic thawing was three times faster than that of tap water, but drip weight loss rate is increased by about 5% during ultrasonic thawing compared to that during thawing in tap water. However, biochemical properties, such as pH, volatile basic nitrogen, thiobarbituric acid, and total aerobic bacteria, were not improved by ultrasonic thawing. Hunter values, such as total color change and redness, improved slightly after 580 kHz ultrasonic thawing. The hardness and chewiness of the pork sirloin decreased significantly after 580 kHz ultrasonic thawing; however, springiness was not changed. These results indicate that ultrasonic thawing is faster than thawing in tap water, but the physicochemical characteristics of frozen pork sirloin was not significantly improve by ultrasonic sound.

• Food Science and Preservation
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• v.21 no.5
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• pp.627-635
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• 2014

We investigated the changes in the quality characteristics of Doenjang with low salt contents (6, 8, 10, and 12%) and 10% garlic. The Doenjang was analyzed at an interval of a week during its fermentation for six weeks, at room temperature. Its L color gradually decreased, but its a and b colors did not change significantly. Its salinity increased by about 1% after six weeks. In contrast, immediately after its preparation, its pH was gradually decreased and its acidity was increased for the fermentation. The reducing sugar was significantly increased from 1.34~1.88 g/100 g immediately after its preparation to 7.25~9.13 g/100 g after six weeks, which was higher as the salt concentration decreased. The amino-type nitrogen doubled from 100~130 mg% at 0 week to 210~290 mg% at six weeks, which were lower with the higher salt concentrations. The growth curve of the Bacillus fermentation strains of Doenjang increased to two weeks but gradually decreased since, and the growth of the Bacillus was favorable for up to two weeks in the Doenjang with 10% and 12% salt added. Otherwise, the yeast was reduced rapidly during the early fermentation of the Doenjang, and slightly changed after three weeks of fermentation. The results of this study showed that the reducing sugar and amino-type nitrogen contents of the low-salt garlic Doenjang were higher with the lower salt dose, and the physicochemical quality of the 6%-salt Doenjang was not significantly affected. Thus, we suggest that low-salt Doenjang can be manufactured with the addition of 6% salt and 10% garlic.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.3
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• pp.343-349
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• 2011

The chemical composition and antioxidative activity of kiwifruit varieties in Jeju, such as Jecy Gold (Actinidia chinensis var. 'Jecy Gold'), Halla Gold (A. chinensis var. 'Halla Gold'), Jecy Sweet (A. deliciosa var. 'Jecy Sweet') and Hwabuk 94 (A. deliciosa var. 'Hwabuk 94') were investigated. The crude protein, crude lipid, and pH showed no differences among variety and maturity whereas the moisture contents showed differences among the variety and maturity. Jecy Sweet in mature stage showed the highest values in soluble solid, crude protein, crude lipid, and crude ash. The changes in chemical components of kiwifruit by maturity stage were as follows: during ripening, the glucose and the fructose contents increased considerably with the decrease of sucrose content. Potassium, phosphorus, sodium, and magnesium were estimated as the major minerals in kiwifruit and Jecy Sweet contained the highest amounts of potassium and magnesium. At maturity stage, ascorbic, malic and lactic acid were increased with the decrease of citric acid content. The polyphenol contents were 26.81~56.10 ${\mu}g/g$ and 8.64~26.45 ${\mu}g/g$, respectively, in immature and mature fruits. During ripening, the polyphenol content was decreased. The DPPH radical scavenging activity of methanol extracts were 84.47~89.37% and 43.94~76.96% at 500 ppm, respectively, in immature and mature fruits. The immature varieties of kiwifruit have a high DPPH radical scavenging activity. Therefore the chemical composition and physiological activity of kiwifruit was affected by variety and maturity.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.8
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• pp.1141-1149
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• 2011

The objective of this study was to analyze quality changes during storage of fresh-cut produce (leafy vegetables and condiment vegetables) as a function of packaging and storage temperature. Fresh-cut produce was washed using a three step cleaning process and was packed in vacuum packaging (green onion, hot pepper, onion, baechu) and perforated film packaging (buchu and perilla leaf). The effects of packaging method and storage temperature on quality of fresh-cut produce were determined by analyzing total plate counts, E. coli, coliform groups, moisture content, pH, Aw, surface color, and exterior quality during storage at 4 and 10$^{\circ}C$. According to the results, surface color change and microbial growth were delayed during storage at 4$^{\circ}C$. Additionally, E. coli was not detected during storage. Generally, moisture content decreased in the perforated film packaging. Changes in surface quality such as skin browning, softening of tissue and chlorosis at 4$^{\circ}C$ were inhibited, whereas rapid vacuum annealing and changes in color and flavor were observed in the sample stored at 10$^{\circ}C$. The result indicated that overall quality of the fresh-cut produce at 4$^{\circ}C$ was well maintained. The perforation in packing materials did not significantly increase the number of microorganisms on buchu and perilla leaf. The proper packaging methods and temperature may beneficial effect on microbial safety, quality and thus result in longer shelf-life fresh-cut vegetables during distribution.

• Food Science and Preservation
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• v.20 no.4
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• pp.554-563
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• 2013

The changes in quality properties and nutritional components for two mugworts, namely, Artemisia capillaris Thumberg Artemisiae asiaticae Nakai fermented by Bacillus strains were characterized followed by rapid pattern analysis of volatile flavor compounds through the SAW-based electronic nose sensor in the GC system. After fermentation, the pH has remarkably decreased from 6.0~6.4 to 4.6~5.1 and there has been a slight change in the total soluble solids. The L (lightness) and b (yellowness) values in the Hunter's color system significantly decreased, whilst the a (redness) value increased via fermentation. The HPLC analysis demonstrated that the total amino acids increased in quantity and the essential amino acids were higher in the A. asiaticae Nakai than in the A. capillaris Thumberg, specially with high contents of glutamic and aspartic acid. After fermentation, the monounsaturated fatty acid increased in the A. asiaticae Nakai and the polyunsaturated fatty acids increased in the A. capillaris Thumberg. While the total polyphenol contents have not been affected by fermentation, the total sugar contents have dramatically decreased. Scopoletin, which is one of the most important index components in mugworts, was highly abundant in the A. capillaris Thumberg; however, it was not detected in the A. asiaticae Nakai. Small pieces of plant tissue in the surface microstructure were found in the fermented mugworts through the use of the scanning electron microscope (SEM). Volatile flavor compounds via electronic nose showed that the intensity of several peaks has increased and additional seven flavor peaks have been produced after fermentation. The VaporPrintTM images demonstrated a notable difference in flavors between the A. asiaticae Nakai and A. capillaris Thumberg, and the fermentation enabled the mugworts to produce subtle differences in flavor.

• Food Science and Preservation
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• v.24 no.1
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• pp.125-133
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• 2017

This study evaluated the changes of physiochemical properties, phytochemical contents, and biological activities during the vinegar fermentation of Elaeagnus multiflora fruit. The contents of pH and reducing sugar decreased from 3.55 and 6.88 mg/mL 3.34 and 2.13 mg/mL, respectively. However the acidity increased from 0.48% to 5.48% during the vinegar fermentation. The alcohol contents increased up to a maximum value of 6.6% at 20 days, and it then decreased at the end fermentation days (2.0%). The viable numbers of acetic acid bacteria and yeasts increased from 4.32 log CFU/mL and 3.23 log CFU/mL at 10 days to 5.4 log CFU/mL and 5.5 log CFU/mL during the spontaneous fermentation, respectively. The major organic acids were acetic acid (38.84 mg/mL), lactic acid (4.92 mg/mL), and malic acid (1.51 mg/mL). The soluble phenolic and flavonoid contents increased from 0.79 mg/mL and 0.12 mg/mL of initial fermentation day to 1.22 mg/mL and 0.14 mg/mL during the spontaneous fermentation. Content of epicatechin gallate decreased from $168.1{\mu}g/mL$ at 10 days to $115.97{\mu}g/mL$. However the content of gallic acid increased from $18.52{\mu}g/mL$ to $95.07{\mu}g/mL$ during fermentation. After 60 days of the fermentation, the antioxidant and digestive enzyme inhibitory activities were 71.35% (DPPH), 79.27% (ABTS), 68.72% (${\cdot}OH$), 85.42% (${\alpha}$-glucosidase), 52.12% (${\alpha}$-amylase), and 53.66% (pancreatic lipase), respectively.

• Korean Journal of Food Science and Technology
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• v.17 no.5
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• pp.389-398
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• 1985

To shorten the processing of cheese slurry, four different slurries, ie, Control, Cheddar 1 and 2, and Italian-type that were made of Na-caseinates, cream, trace elements, lactic culture, and enzymes were fermented at $30^{\circ}C$ for 7days with daily stirring. PH, titratable acidity, soluble nitrogen, viable cell count, active SH groups, total volatile fatty acid, free fatty acid, electrophoretic patterns of degraded caseins, and viscosity were analyzed to investigate physicochemical properties of fermented slurries. Acid production was accelerated in the cheese slurries with protease than that without the enzyme and PH of the former was decreased after three days of fermentation to 4.90. The Change of titratable acidity agreed to PH patterns. Soluble nitrogen of the Control slurry was increased slowly for four days and then rapidly to 40% of total nitrogen while those containing protease to 70%. The protease of lactic cultures used (Streptococcus lactis and Streptococcus cremoris) broke down as-casein more rapidly than $\beta$-casein and most proteins were degraded to peptides and amino acids after three days of fermentation. Total volatile fatty acids were increased by added lipase and free fatty acids composition analyzed by GLC in cheddar slurry with 0.00001% lipase was similar to that of commercial cheddar cheese, while that in Italian-type slurry was a half of that in commercial Italian cheese. Active SH groups were increased in the cheese slurries with glutathione from fourth day of fermentation. The viscosity of slurries decreased very rapidly by addition of protease.