• Korean Journal of Food Science and Technology
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• v.34 no.6
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• pp.1091-1097
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• 2002

In order to improve palatability and quality of traditional kochujang, kiwifruit (Actinidia deliciosa) was added to traditional kochujang fermented for 3 months. Physicochemical and microbial characteristics were investigated during fermentation at $30^{\circ}C$. Moisture contents of all treated kochujangs increased with increasing amount of kiwifruit added during fermentation. pH of kiwifruit-added kochujang was lower than that of the control kochujang, whereas no significant differences in titratible acidity was observed among all treatments. Crude protein and salt contents of kiwifruit-added kochujang were lower than those of the control, whereas no difference in crude fat contents were found. Ethanol and amino-nitrogen contents of 6 and 9% kiwifruit-added kochujang were higher than those of the control. Fructose contents of kiwi-added kochujangs were higher than that of the control. Major organic acids of kochujang were in the order of malic acid > citric acid > succinic acid > acetic acid > lactic acid > oxalic acid. Succinic acid level increased significantly during fermentation and was higher in kiwifruit-added kochujang than in the control. Bacterial cell counts of all treatments were not different, and viable cell count of yeast was slightly higher in kiwifruit-added kochujang only at the initial fermentation period. Sensory evaluation revealed that the addition of 9% kiwifruit was the optimum condition for improving kochujang quality.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.5
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• pp.819-825
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• 2001

Characteristics (salt concentration, weight loss, soluble solid content, moisture content, pH, textural properties) of kakdugi radish cube (2$\times$2$\times$2 cm) were evaluated during salting. Four different radish cultivars harvested in spring were immersed into 5, 10 or 15% brine (radish : brine - 1 : 2) at 15$^{\circ}C$ for 5 hr. The time required to reach the optimum salt concentration (3.0%) was different among cultivars; in 10% brine solution, 5 hr for ‘Bakbong’and ‘9621’, and 4 hr ‘Bagkwang’ and ‘Housebommu’, in 15% brine, 3 hr for ‘Bakbong’and ‘9621’, and 2 hr for ‘Bagkwang’and ‘Housebommu’. While the highest value of weight loss of kakdugi radish cube was observed with ‘Bagkwang’, the lowest, ‘Bakbong’. There was a decrease of pH of kakdugi radish during salting ; while ‘Bakbong’ showed little change in pH, ‘Bakbong’and ‘Housebommu’ showed large decrease of pH. Hardness and fracturability decreased during salting; the highest value of hardness was observed with ‘Bagkwang’, the lowest, ‘Bagkwang’. ‘Bakbong’ has the lowest moisture content, but the highest soluble solid content, while ‘Bagkwang’and ‘Housebommu’ have the highest moisture content, but the lowest soluble solid content. There was a similarity of characteristics of kakdugi radish cube between two cultivars, ‘Bagkwang’and ‘Housebommu’.

• Journal of the Korean Society of Food Science and Nutrition
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• v.12 no.4
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• pp.316-322
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• 1983

In order to obtain elementary data of enzymatic browning of apples and apple products and to examine effectively inhibitory method of browning, we extracted polyphenol oxidase (EC 1.10.3.1) from apple (Ralls Janet) and investigated its general properties. The optimum conditions for the enzyme reaction were pH 6.0 and temperature of $30^{\circ}C$. The enzyme was very stable at pH 4.0, and at the range of pH 5.0-9.0 its activity was above 80% compared with pH 4.0. The enzyme was very stable by heating at $40^{\circ}C$ for 1 hour, and almost 50% of enzyme activity was lost by heating at $60^{\circ}C$ for 30 minutes. The polyphenol oxidase activity was enhanced by the addition of $Cu^{2+}$ and $Mn^{2+}$, respectively, meanwhile $Na^+$, $Hg^{2+}$ and $Co^{2+}$ inhibited the enzyme activity. The enzyme activity was greatly decreased in the presence of inhibitors such as cysteine, sodium metabisulfite and ascorbic acid. The polyphenol oxidase greatly catalyzed the oxidation of o-diphenols such as chlorogenic acid and catechol, which suggests that main substrate of polyphenol oxidase is o-diphenol compounds.

• Elastomers and Composites
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• v.40 no.2
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• pp.93-103
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• 2005

In this study, surface treatment of the elastomeric matrix was investigated to develop a substituting material for steel dynamic damper of automobile. The key technology is to get ultra high density elastomeric compound in order to substitute steel dynamic damper. The optimum matrix material(chloroprene rubber) and filler(metal powder) were selected for this. The several properties of elastomeric compound were examined. According to the results, the $t_{s2}$ of filled elastomeric compound was decreased with increasing the filler loading whereas the $t_{90}$ was increased. Also, tensile strength and rebound resilience were decreased with filler loading. To solve the problem of high filler loading, the photo grafting technique was employed on elastomeric matrix. The degree of grafting was determined by FTIR-ATR. Also, the filler surface was modified by chemical etching and the surface morphology was examine by SEM. After chemical treatment of filler, the particle size analyzer was used to examined the particle size, size distribution, and morphology of the modified filler.

• Food Science and Preservation
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• v.18 no.3
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• pp.414-422
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• 2011

The optimum condition for phenolics contents extraction from purple sweet potato was 12 hrs. in 50% ethanol. The electron donating scavenging activities (DPPH), ABTS radical cation decolorization (ABTS) and antioxidant protection factor (PF) of Jami, Yeonjami and Shinjami were higher than general sweet potato, and thiobarbituric acid reaction substance (TBARs) was below 30%. The minimum inhibitory concentration (MIC) against Staphylococcus aureus and Escherichia coli on skin were each 5,000 and 2,500 ppm in all purple sweet potatoes, and MIC of Jami was the lowest as 2,500 ppm against Staphlococcus epidermidis. The whitening (tyrosinase inhibitory) activity of purple sweet potatoes was the highest as 62.5% and 48.7% in Jami water and ethanol extracts. The anti-inflammation (hyaluronidase inhibitory) activity of purple sweet potatoes was the highest as 25.3% and 94.4% in Jami water and ethanol extracts. The safety of cosmetic with Jam; extracts was assessed by various safety profiles. pH and viscosity change of essence for 90 days was not detected. Cosmetic was stable to temperature and light for 90 days. The result to measure changes of skin color and pore size of the skin was that an aged skin was more effective than young skin.

• Food Science and Preservation
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• v.19 no.4
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• pp.463-469
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• 2012

In this study, the anti-oxidant and anti-elastase activities of four abalone viscera extracts were investigated to screen the most promising extract. This extract was further studied in terms of its anti-skin-aging properties. In the DPPH-scavenging assay, the Tris-HCl extract showed a $58.60{\pm}0.88%$ radical-scavenging activity, which was followed closely by the ethanol extract that had a $55.40{\pm}0.62%$ scavenging activity. In the anti-elastase assay, however, the ethanol extract showed the significantly highest elastase inhibition activity. Furthermore, none of the extracts had a harmful effect on the human dermal fibroblast, as revealed in the MTT assay. In the cell study, the effect of the ethanol extract at various concentrations on the human dermal fibroblast was investigated. At the 10 ${\mu}g/mL$ concentration, the ethanol extract boosted the pro-collagen type I synthesis to $705.30{\pm}3.06$ ng/mL and reduced the MMP-1 to $54.30{\pm}0.80$ ng/mL, which was considered the optimum concentration. This is the first study that focused on the anti-oxidant and anti-skin-aging effects of abalone viscera extract. Its results may provide fundamental data for further study.

• Korean Journal of Food Science and Technology
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• v.53 no.6
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• pp.739-748
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• 2021

This study focuses on the use of rice in the production of gluten-free rice udon (GFU) through an optimized mixing ratio, using the Box-Behnken response surface methodology (RSM). Different additional levels of rice flour (A, 40-60 g), acetylated distarch adipate (B, 10-20 g), and trehalose (C, 0-3 g) were used as variables, while water absorption level, volume, cooking loss, solid yield, lightness, texture properties, proximate compositions of GFU and turbidity of cooking water were set as responses in the RSM design model. The optimum mixing ratio for the preparation of gluten-free rice udon was obtained for 60.00 g of rice flour, 18.81 g of acetylated distarch adipate without the addition of trehalose. The response values of the optimized samples were water absorption (60.94%), volume (34.94%), turbidity of the cooking water (0.37), cooking loss (4.77%), solid yield (1.55 g), lightness value (70.04), hardness (2.53 N), springiness (0.18), gumminess (10.45 N), chewiness (1.83 N), and cohesiveness (2.89). This study has shown that rice flour can replace wheat flour to manufacture udon at an optimized mixing ratio successfully derived by statistical estimation method.

• Food Engineering Progress
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• v.13 no.1
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• pp.16-23
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• 2009

Onion juices supplemented with different concentrations of puffed red ginseng extract were fermented using Pediococcus pentosaceus KC-007 and their biologically functional properties were investigated. When onion juices were supplemented with puffed red ginseng extract at the concentration of 0.5, 1, 2, and 4% (v/v) each, viable cell number of lactic acid bacteria was the highest at 24 hr of fermentation in all samples. The titratable acidity increased as the fermentation proceeds irrespective of the added amount of red ginseng extract, and the pH of fermentation broth decreased until 36 hr of fermentation. The reducing sugar of fermentation broth decreased until 24 hr of fermentation and did not change thereafter. The electron donating ability and nitrite scavenging ability were highest when red ginseng extract was added at the concentration of more than 1% (w/v). The overall acceptance in sensory evaluation was the best when red ginseng extract was added at the concentration of 1% (w/v). From these results, it is confirmed that the optimum concentration of puffed red ginseng extract for the lactic acid fermentation of onion juice was 1% (w/v).

• Journal of the Korean Recycled Construction Resources Institute
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• v.7 no.1
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• pp.37-43
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• 2019

This research studied production of lightweight filling production for sink hole restoration utilizing various industrial by-products(2kinds of fly ash, petro-cokes CFBC ash, blast furnace slag fine particle). For this purpose, the mixed raw material properties(compressive strength) behaviors according to the blending ratio of industrial by-products were examined by applying the experimental design method and statistical analysis was performed using the commercial program MINITAB. Compressive strengths of industrial by-products were strongly dependent on blast furnace slag powder. Compressive strength(3days aging) was 3~11MPa depending on the amount of blast furnace slag powder used. The use of CFBC fly ash was evaluated to have the least effect on compressive strength. In addition, the compressive strength and the coefficient of permeability were measured by preparing foamed concrete for the experimental batch 1 condition in the mixture experimental design. In this case, the bulk density is 0.9 to 1.0, the apparent porosity is 30 to 50%, the compressive strength(3days old) is 1 to 2MPa, and the permeability coefficient is $10^{-2}$ to $10^{-3}cm/sec$.

• Food Engineering Progress
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• v.21 no.2
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• pp.167-173
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• 2017

Purple-fleshed potato powder (PFPP) was investigated to determine optimal mixing ratio with milk powder and dextrin to produce a ready-to-eat mashed potato powder. The rheological characteristics, color, and anthocyanin contents were studied at a different concentration of ingredients. The power-law model was applied to explain the mechanical spectra of mashed potatoes which represented the change in structure induced by different mixing ratios. Mixture design was used to obtain the experimental points used to establish the empirical models to describe the effects of each ingredient on the characteristic of the mashed potato. The results of mechanical spectra showed that both storage and loss moduli (G' and G'') were significantly influenced by PFPP and milk powder concentration. The power law parameters n' and n'' showed higher values for the mashed potato with a lower concentration of PFPP and a higher concentration of milk powder, which showed that the gel networks involved in the mashed potato were weaker. The optimum mixing ratio with the highest redness and anthocyanin content, while maintaining the rheological properties similar to the commercial mashed potato, was determined as PFPP:milk powder:dextrin = 90.49:4.86:4.65 (w/w). The proportions of PFPP and milk powder in the formulation significantly changed the characteristics of mashed potato, whereas no significant effect of dextrin was observed in this formulation.