• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.2
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• pp.189-195
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• 2002

Corn starch was modified by oxidation with sodium hypochlorite (NaOCl) as an attempt to expand the application of starches in food industry. Corn starch was oxidized with 0.25, 0.5, 0.75, 1.0 and 1.5% active Cl/g starch at pH 7.0 and $25^{\circ}C$ for 10 minutes. The size, shape and amylose content of oxidized starches were similar to those of native corn starch. As the extent of oxidation increased, solubility, swelling power and the amount of soluble amylose increased, X-ray diffraction patterns changed, and relative crystallinity decreased. In Brabender amylogram, oxidation did not chance the gelatinization temperature, but oxidized starches had a lower peak in viscosity and their cooled pastes gave less setback, compared with native corn starch.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.12 no.1
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• pp.56-61
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• 2002

Porous clay ceramics was fabricated using the surfactant as a foaming agent in the secondary-clay produced at Young-Am area in Chun-Nam province. The concentration of surfactant in ceramic slurry was the key factor controlling the pore characteristics and physical properties of the porous ceramics. The more increase of the surfactant concentration increase the more foaming ability and the stability of foamed layer were improved, but the foaming ability was limited within 6.0 wt% of surfactant because the initial viscosity of the slurry increased with increasing the amounts of surfactant. The formed specimen were sintered at both $1150^{\circ}C$ and $1200^{\circ}C$, the porous ceramics showed 0.9 of specific gravity, 50% of water absorption, 45% of apparent porosity, 14% of shrinkage and 70 kg/$\textrm{cm}^2$ of compressive strength.

• Applied Biological Chemistry
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• v.38 no.3
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• pp.232-238
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• 1995

Quality changes of high fructose corn syrups (HFCS) were investigated during storage at $-5{\sim}60^{\circ}C$. Color properties such as spectrophotometric properties, HMF and Hunter color value increased continuously during storage period. And the change was most evident as storage temperature and fructose content were elevated. High fructose corn syrups all showed flow behaviors as dilatant fluid and their viscosities increased slightly during storage. Content of fructose decreased, while glucose, maltose and oligosaccharide contents increased during storage. Especially, crystallization of what was observed below $13^{\circ}C$ during storage.

• Applied Biological Chemistry
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• v.37 no.3
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• pp.154-160
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• 1994

Pregelitinized rice (PR), pregelitinized waxy rice (PWR), and pregelitinized rice flour (PRF) were evaluated for physico-chemical properties comparing with rice starch and acetylated potato starch. L value was decreased during drum drying. PFR had the highest value (P<0.05) for water absorption index and PWR had the highest value for water solubility index. Transmittance of gelitinized samples had drastically increased at $80{\sim}90^{\circ}C$. PWR had the highest value for apparent viscosity and rice samples had a steady apparent viscosity during heating at $90^{\circ}C$. Viscosity was decreased as pH decreased at room temperature and drastically decreased below pH 2. Rice starch and PR had no significant effect for change of pH. Change of viscosity had more effect for hot temp. than room temp.. Pregelitinized samples showed only second peak for DSC. PWR had the lowest value for degree of retrogradation and acetylated potato starch had the highest value for freeze-thaw-stability.

• Korean journal of food and cookery science
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• v.29 no.2
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• pp.129-135
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• 2013

The objective of this research was to investigate physicochemical properties of waxy sorghum flours by different milling methods (pin mill and ultra fine mill). Four different sorghum flours were used for the experiments ; PWS (pin milled whole sorghum flour), PS (pin milled sorghum flour without bran), UFWS (ultra fine milled whole sorghum flour), UFS (ultra fine milled sorghum flour without bran). The contents of crude ash and total dietary fiber were the highest in PWS. Amylose content of pin milled sorghum flour was higher than that of ultra fine milled flour. The mean particle size of pin milled flours was six times lager than ultra fine milled flours. The L values of UFS and UFWS were higher than those of PS and PWS, whereas a and b values were higher in PWS. The water binding capacity was highest in UFWS, and solubility was higher in PS and UFS. Swelling power of flours was highest in UFS. The damaged starch content was higher in PS and UFS, which means damaged starch of sorghum flours significantly affected by polishing than milling method. The pasting properties were higher in the pin milled flours. Initial pasting temperature of pin milled flour was ranging from 70.5 to $73.1^{\circ}C$, which are higher than ultra fine milled flour ($68.6^{\circ}C$). The contents of total polyphenol were higher in PWS and UFWS than those of PS and UFS, there was no difference between the two milling methods. The results of this study indicate that physicochemical properties of sorghum flour were affected by milling methods as well as bran.

• Korean Journal of Agricultural Science
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• v.26 no.1
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• pp.71-76
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• 1999

The methanolic extracts from the elm (Ulmus davidiana var japonica) root barks which have been known as an oriental medicine Eubackpie for the treatment of edema, ulcer and inflammation were examined for their bacteriocidal effects on mastitis pathogens of milk cows. The growth of the pathogenic bacteria such as Staphylococcus aureus and Streptococcus sp. No. 12 was markedly inhibited by the chloroform fraction among the extracts, and these antibacterial activities were also supported by MIC test. Water-soluble mucilage was obtained from the root barks with a yield of 36.8~40.2% by dry weight basis. This substance appeared to be a kind of polysaccharide with $61.0{\pm}1.0%$ carbohydrate content, and to have hygroscopic and astringent properties due to its high viscosity and water absorption.

• KSBB Journal
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• v.11 no.3
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• pp.340-346
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• 1996

Variations of rheological properties of culture broth during the production of biopolymer by an alkali tolerant Bacillus sp. were investigated. Correlations among the rheological characteristics of culture broth, cell growth and biopolymer production were examined. Rheology of the culture broth changed in the course of fermentation. The culture broth showed a non-Newtonian flow behavior, as the viscosity and pseudoplasticsity increased during the cultivation. The rheological parameters such as flow index, consistency index, yield stress and apparent viscosity during the cultivation were not influenced by the cell growth, but significantly related to the biopolymer synthesis. Changes in the rheological parameters of the broth were affected not only by the biopolymer concentration, but also by the progress of fermentation. Some rheological parameters showed maximum values just before the completion of biopolymer production and substrate consumption. Hence, it was shown that the rheological characteristics of the culture broth could be used as a good indicator for the detection of the progress or completion of fermentation.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.7
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• pp.1048-1052
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• 2011

This study examined the flow properties, paste clarity, freeze-thaw stability and gel strength of acetylated sweet potato starch (ASPS) pastes and gels as a function of degree of substitution (DS). ASPS showed high shear-thinning flow behaviors with high Casson yield stress ($\sigma_{oc}$). Consistency index (K), apparent viscosity ($\eta_{a,100}$) and $\sigma_{oc}$ values of ASPS increased with an increase in DS. In the temperature range of $25{\sim}70^{\circ}C$, ASPS followed an Arrhenius temperature relationship. The activation energies (Ea=13.2~14.3 kJ/mol) of the ASPS samples were much lower than that (18.1 kJ/mol) of the native sweet potato starch (SPS). ASPS gels showed better freeze-thaw stability with a significant decrease in syneresis (%) compared to SPS gel. The gel strength values of ASPS were much lower than that of SPS, and significantly decreased with an increase in DS. The clarity of native SPS paste increased after acetylation.

• Journal of the Korean Ceramic Society
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• v.41 no.4
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• pp.277-283
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• 2004

To fabricate green sheet of transparent dielectric for PDP front panel, dispersion of transparent dielectric slurry, density, and mechanical properties of green sheets have been investigated as a function of amount and composition of organic additives. Measurements of sedimentation and viscosity were employed to determine a proper dispersant and its amount for a well dispersed transparent dielectric powders in non-aqueous system. Green sheets, having various ratios of transparent dielectric powders to transparent dielectric powders＋ binder＋plasticizer and binder to binder＋plasticizer, were fabricated. All the tape casting slurries showed shear thinning effect, that is, the apparent viscosity decreased with the increase of shear rate. It was found that the amount and composition of organic additives were main variables to affect densities and mechanical properties of transparent dielectric green sheets for PDP.

• Applied Chemistry for Engineering
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• v.28 no.6
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• pp.714-719
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• 2017

The contaminated engine oil by fuel can intimidate driver safety due to vehicle problems such as engine abrasion, fire and sudden unintended acceleration. In this study, we investigate various functional properties of the engine oil contaminated with fuel. The test results indicated that the engine oil contaminated with fuel had relatively low values of the flash point, pour point, density, kinematic viscosity and cold cranking simulator. Furthermore, a four ball test suggested that the contaminated engine oil increased wear scar due to the poor lubricity. Moreover, SIMDIST (simulated distillation) using ASTM D2887 was applied to analyze fuel characteristics in an engine oil. The SIMDIST analysis result showed a lower carbon number, and the fuel was detected at an earlier retention time than that of using engine oil in chromatogram. Also, it is possible to quantitatively analyze for fuel contents in the engine oil. The SIMDIST method for the diagnosis of oil conditions can be used whether the fuel was involved or not, instead of analyzing other physical properties that require various analytical instruments, large volumes of oil samples, and long analysis time.