• Applied Biological Chemistry
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• v.31 no.1
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• pp.46-51
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• 1988

The effects of temperature on the water uptake rate of soybeans soaked in tap water and 0.5% $NaHCO_3$ solution were studied. The higher the soaking temperature, the faster the hydration rate, and among the three soybean varieties (Tanyob, Kwanggyo and Saeal), Tanyob(the smallest variety) showed faster rate than ocher varieties when soaking in tap water and 0.5% $NaHCO_3$ solution. Activation energy due to weight increase was calculated using Arrhenius equation. z-Values calculated from weight changes to reach different degrees of hydration during soaking showed the tendency to decrease with the increase of hydration degree when soaking in tap water and 0.5% $NaHCO_3$ solution.

• Journal of the Korean Society of Food Culture
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• v.31 no.5
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• pp.481-488
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• 2016

The objective of this study was to investigate the antioxidant and anti-inflammatory activities of Eugenia caryophyllata Thunb. water and 70% ethanol extracts. The content of total polyphenol was significantly higher in water extract than in 70% ethanol extract. The DPPH radical scavenging activity of water extract was similar to that of Vit. C at a concentration of $1,000{\mu}g/mL$. The ABTS radical scavenging activities of water and 70% ethanol extract were similar to that of Vit. C at a concentration of $1,000{\mu}g/mL$. SOD-like activity of water extract was higher than that of 70% ethanol extract at a concentration of $1,000{\mu}g/mL$ but lower than that of Vit. C. The DPPH radical scavenging activity, ABTS radical scavenging activity, and SOD-like activity increased as concentrations of water and 70% ethanol extracts increased. Cell cytotoxicity was not observed at all concentrations except at $100{\mu}g/mL$ concentration of water extract. Inhibitory activity on NO production effect of water extract was significantly higher than that of 70% ethanol extract. These results show that E. caryophyllata Thunb. has potent biological activities, and their activities were different depending on extraction solvent.

• Korean Journal of Food Science and Technology
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• v.47 no.1
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• pp.6-12
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• 2015

This study was performed to determine the optimal hydrolysis conditions for the production of hydrolysates, including water-soluble dietary fiber from Chinese cabbage, with commercial enzymes. The optimal pH and temperature for hydrolysis of the hemicellulose fraction were pH 5.0 and $40^{\circ}C$, and optimal enzyme concentrations were 45 units and 21 units for Shearzyme plus and Viscozyme L, respectively. The yields of the hydrolysate including the water-soluble dietary fiber from the hemicellulose fraction by Shearzyme plus and Viscozyme L were 22.64 and 24.73%, respectively, after a 72 h reaction. The molecular weight distribution of alcohol-insoluble fiber was characterized by gel chromatography; degradation of hemicellulose increased with increasing reaction time. Our results indicate that the hemicellulose fraction was degraded to water-soluble dietary fiber by enzymatic hydrolysis, and its hydrolysate could be utilized as new watersoluble food materials.

• Korean Journal of Food Science and Technology
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• v.26 no.6
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• pp.740-744
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• 1994

This study was undertaken to prove the suppressing effect of green tea on the intestinal absorption of heavy metals using in vitro membrane filtration system. From drinking water contaminated with 10 and 100 times level of water quality standard for heavy metals, the removal ratio of lead (Pb) was $50{\sim}70%$ by green and black teas, and $30{\sim}40%$ by roasted barley tea. The removal ratio of cadmium (Cd) was $30{\sim}40%$ by green tea and black teas, and $10{\sim}20%$ by roasted barley tea. The removal effect from drinking water contaminated with both lead and cadmium was lower than that from water contaminated singly with lead or cadmium. It appears that tea components and filter membrane compete toward the adsorption of two heavy metals. Among the extraction conditions of raw tea materials at $70^{\circ}C$, 2 minutes and $95^{\circ}C$ , 10 minutes, the removal ratios of heavy metals were similar.

• Korean Journal of Agricultural Science
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• v.43 no.2
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• pp.249-257
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• 2016

In this study, rapeseed extracts were obtained by supercritical carbon dioxide fluid extraction of defatted rapeseed to evaluate the stability and antioxidant activity of an oil-in-water (O/W) emulsion system. The oil-in-water emulsions were prepared from stripped soybean oil with different concentrations (0.3, 0.4, 0.5, and 0.6%) of rapeseed extract as an emulsifier. Their emulsion stability was compared to that of emulsions prepared with the commercial emulsifier, Tween 20 (Polysorbate 20, 0.2%). After stripping the soybean oil, the total tocopherol content was reduced from 51.4 g/100 g to 1.1 g/100 g. Emulsion stability and oxidative stability of emulsions prepared with Tween 20 and rapeseed extract as emulsifiers were evaluated. For 30 days droplet sizes of emulsions containing rapeseed extract (0.4, 0.5, and 0.6%) were not significantly different (p > 0.05). Similar results were obtained for emulsion stability (ES) and Turbiscan analysis, suggesting that the addition of rapeseed extract increased emulsion stability. The addition of rapeseed extract at more than 0.4% resulted in an emulsion stability comparable to the addition of 0.2% Tween 20. The antioxidative ability of rapeseed extract increased with the amount added in the emulsion. Moreover, the addition of 0.6% rapeseed extract resulted in the lowest emulsion peroxide values (10.3 mEq/L) among all treatments. Therefore, according to the stability of its antioxidative and physical stability properties, rapeseed extract from super critical extraction could be successfully applied to the food and cosmetic industries.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.31 no.1
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• pp.77-81
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• 1998

A bacteriological study of sea water in Deukryang Bay was conducted to evaluate sanitary conditions of the bay and compliance of waters with the recommended bacteriological criteria for the designated area of shellfish cultivation. Sea water samples were collected at the established sampling stations (fig. 1) from May 1995 to November 1996. During the study period, coliform group, fecal coliform, classification of coliform group with IMViC reactions and pathogenic vibrios were analyzed. Coliform group and feral coliform MPN's were ranged from $<\;3.0\~4600/100m{\ell}\;and\;<\;30\~1,100/100m{\ell}$, respectively. The bacteriological criteria of sea water in shellfish growing area should be less than 70 per l00ml of sea water for median value of coliform MPN, and below $10\%$ of the samples which contain over than 230 for coliform MPN or over than 43 for fecal coliform MPN, Most of the waters from 26 sampling stations were complied water coliform criteria recommended for designated shellfish growing area. Then, the ratios of the samples with move than 230/10ml of coliform group MPN and more than 43/100ml of fecal coliform MPN were $7.4\%$ and $8.5\%$, respectively. The bacterial density of the sea water was deeply affected by rainfall amount. For example, coliform bacterial counts of sea watery after 48 hours from 93 mm rainfall were $6\~7$ times higher than those of without rainfall. During the study period, infectious bacteria such as Vibrio cholerae, Salmonella sp. an d Shigella sp. were not detected from the samples, but detection ratios of Vibrio parahaemolyticus and Vibrio vulnificus were $15\~20\%$ in summer months.

• Food Science and Preservation
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• v.7 no.3
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• pp.291-296
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• 2000

The present study was conducted to investigate antioxidant, nitrite scavenging and alcohol degradation effects of extracts from leaf and fruit stalk of Hovenia dulcis. Yields of various solvent extracts for Hovenia dulcis leaf and fruit stalk of were higher in water and methanol extract layer, respectively. Ethanol extracts of Hovenia dulcis leaf and fruit stalk of were fractionated with different solvents such as hexane, chloroform, ethyl acetate, butanol and water, yields of water fraction were highest. In the solvent extracts using methanol, ethanol, hexane, chloroform and water, ethanol extracts showed the most effective antioxidant and nitrite-scavenging effects. Ethanol extracts from Hovenia dulcis leaf and fruit stalk of were fractionated, the most natioxidant and nitrite-scavenging effects were ethyl acetate fraction. Alcohol degradation effects from different parts of Hovenia dulcis showed higher leaf and fruit stalk than xylem, branch and seed. Alcohol degradation effects from leaf and fruit stalk increased as time passed.

• Journal of The Korean Digital Architecture Interior Association
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• v.12 no.1
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• pp.53-59
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• 2012

This research studied the characteristics of the customer circulation in four department store food court restaurants located in Seoul. The characteristics of the customer circulation are the following: Before customers leave the dining space where they eat food, they come and go to spaces such as the water purifier space, the napkin storage, and the cup storage. On the other hand, they do not come and go from the dining space to the waste area or the area where used cups are returned. Therefore the spaces, that need to be located very near the dining space, are the water purifier space, the cup storage, and the napkin storage. The waste area does not have to be placed very near the dining area and the area where used cups are returned is not needed. A minority of customers drink water and use napkins after going to the waste area and the area where dirty dishes are kept. To prevent these customers from going against the circulation of the majority of customers, a water purifier space, a cup storage, and a napkin storage should be placed additionally connecting to the waste area and the area where dirty dishes are kept. For effective circulation plan and spatial composition of food court restaurants, these characteristics of customer circulation should be considered. It is not recommended to place the water purifier space, the napkin storage, and the cup storage, the waste area or the area where used cups are returned, and the hand cleansing facility in the same location just for the convenience of workers.

• Korean Journal of Food Science and Technology
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• v.53 no.3
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• pp.329-333
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• 2021

Subcritical water extraction (SWE) is an eco-friendly extraction method that uses only purified water as a solvent under high temperature and high pressure conditions. In this study, total phenolics, and antioxidant activity were evaluated in Ziziphus jujuba Mill extracts from subcritical water obtained by varying the extraction temperature (110-190℃) and extraction time (1-20 min). Total phenolics was maximized with extraction at 190℃ for 15 min (67.79±3.45 mg gallic acid equivalent/g jujube). The 2,2-diphenyl-1-picrylhydrazyl free radical scavenging activity (48.84±4.74%) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) free radical scavenging activity (84.75±1.15%) were maximal at extraction conditions of 190℃, for 20 min. All jujube extracts prepared using SWE had higher total phenolics and antioxidant activities than extracts prepared using organic solvent extraction (60℃, 120 min), including methanol and ethanol. SWE could be an excellent alternative to organic solvents for extracting phenolics and antioxidant compounds.

• Korean Journal of Food Science and Technology
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• v.29 no.5
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• pp.1033-1037
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• 1997

The occurrence of mold growth due to moisture migration in a composite chocolate product filled with marshmallow during storage was investigated. The correlation between water activities and water contents of dark chocolate coating and filling marshmallow at $25^{\circ}C$ was well applied to Kuhn's equation. The marshmallow was found to be more hydrogroscopic than the chocolate. Since the moisture transferred from marshmallow to chocolate, the water activity of marshmallow decreased from 0.88 to 0.80 and that of chocolate increased from 0.22 to 0.76 at $25^{\circ}C$ for 30 days. This water activity, 0.76, can allow mold growth. A mold was isolated on the surface of a composite chocolate product at $25^{\circ}C$after 3 months and then was identified as Aspergillus repens. Growth experiments at varied water activities with A. repens were performed. When the water activity in a chocolate solid medium increased from 0.73 to 0.93, the occurrence time of mold growth decreased from 62 to 15 days. These results suggested that the occurrence of mold growth was due to the increased water activity of the chocolate resulting from the moisture transfer from filling marshmallow dark to chocolate coating.