• Korean Journal of Food Science and Technology
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• v.28 no.3
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• pp.573-579
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• 1996

Crosslinked potato starches (XP), from 2,400 to 1,900 anhydroglucose units per crosslinked (AGU/CL), were prepared by reacting with epichlorohydrin. Some of the physicochemical properties of the XPs were then compared with those of native potato and cowpea starches. Crosslinking decreased moisture, protein and ash contents but had no effect on phosphorus content. Water binding capacities of the XPs increased as the degree of crosslinking increased, and that of the XP with 2,100 AGU/CL approached the value of cowpea starch. The absorption maxima of the starch-iodine complex shifted from 594 to 580 nm. Granule size increased slightly and surface appearance of the granule became rough when crosslinked. Both native and crosslinked potato starches showed B type X-ray diffraction pattern, and the relative crystallinity was not affected by crosslinking. Gelatinization temperature and the heat of gelatinization, measured by differential scanning calorimeter (DSC), did not change within the range of crosslinking tested. From X-ray and DSC data, it was concluded that the crosslinking ocurred in the amorphous region of the starch granule.

• Journal of the Mineralogical Society of Korea
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• v.18 no.3 s.45
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• pp.183-194
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• 2005

The mineralogical, physicochemical and thermal properties of the Myogi bentonite occurring in Japan were measured. A adsorption properties of U, Th, Ce and Eu ions on the Myogi bentonite were also investigated in different solution concentrations and pH conditions. The Myogi bentonite showed a strong alkaline character (pH 10.4), very high swelling, viscosity property and CEC, and a slow flocculation behavior due to the strong hydrophilic property. By the thermal analysis, the dehydroxylation of crystal water in bulk and clay fractions of the Myogi bentonite occur at $591^{\circ}C$ and $658^{\circ}C$, respectively, The adsorption experiments of ions such as U, Th, Ce and Eu were conducted for 0.2 g bentonites with 20mL solutions of various concentrations and different pH conditions with pH 3, 5, 7, 9, and 11. As a result, the Myogi bentonite showed excellent adsorption capacities for Ce, Th and Eu ions, whereas U ion showed very low adsorption capacity. Generally, Ce, Th and Eu ions showed the similar adsorption properties for the different concentrated solutions and pH conditions. These adsorption properties seem to be affected by the formation of various forms of chemical species and precipitation as well as ionic exchange reaction and surface adsorptions on smectite. Some associated zeolite minerals perhaps have some effects on the adsorption of U, Th, Ce and Eu on Myogi bentonite.

• Journal of the Korean Society of Food Science and Nutrition
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• v.23 no.6
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• pp.1014-1019
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• 1994

To develope natural food preservatives, ethanol extract was preapred from the leaf mustard (Brassica juncea Coss) and antimicrobial activities were examined against 12 microorganisms which were food borne pathogens and/or food poisioning microorgaism and food-related bacteria and yeasts. The most active animicrobial concentration of the ethanol extract for most Gram positive microorganisms, Gram negative microorganisms, and lactic bacteria and yeasts was found to be 10, 20 and 40 mg/ml, respectively. when tested by a dose-response manner. Growth of Escherichia coli and STaphylococcus aureus were completely inhibited 4 hours after the addition of more than 20mg/ml of ethanole ethanol extract to the logarithic phase. Scanning electron icrographs of E. coli and Staph, aureus treated with ethanol extrract exhibited morphological changes, including the irregularly contracted cell surface of E. coli and expanded ellipsoidal shape of the Staph. aureus.

• Korean Journal of Food Science and Technology
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• v.33 no.1
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• pp.60-65
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• 2001

Physicochemical properties of 4 kinds of domestic and 7 kinds of foreign starch vermicelli (1 from Chinese, 6 from Japan) were determined. Peak temperature of starch vermicelli measured by DSC were $42{\sim}48^{\circ}C$ which were much lower than gelatinization temperatures of their raw material starches. X-ray diffraction peaks of starch vermicelli were not sharp compared with those of raw material starches which indicated that starches were gelatinized by heating and retrograded by cooling and freezing during production of starch vermicelli. Hardness and compression slope of sweet potato starch vermicelli measured by rheometer were respectively $9,500{\sim}11,000\;g/cm^2$ and $18,000{\sim}26,000\;g/cm^2$ which were twice higher than those of corn starch vermicelli. Cooking loss of corn starch vermicelli, which was 19.8%, was higher than that of sweet potato starch vermicelli, $4.2{\sim}6.6%$ and mung bean starch vermicelli, 7.7%. In changes of thickness of starch vermicelli during cooking i.e swelling ratio, sweet potato starch vermicelli had $58{\sim}69%$ of swelling ratio, which was higher than that of corn starch vermicelli, 50%. Corn starch vermicelli, which was relatively less elastic and easily broken, was shown to be inferior to that of sweet potato starch vermicelli in overall quality.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.10a
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• pp.223.1-223
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• 2003

인산 쌀 전분을 제조, 이용하기 위한 기초 자료를 얻기 위하여 추청벼와 삼강벼를 원료로 하여 쌀 전분을 제조하고 이에 15% sodium tripolyphosphate를 가하여 15$0^{\circ}C$에서 30분간 반응시켜 얻어진 인산 쌀 전분(D. S.=0.015)의 이화학적 성질을 검토하였다. 인산 쌀 전분의 투명도는 원료 전분에 비하여 높았으며 원료 전분은 6$0^{\circ}C$, 인산 쌀 전분은 5$0^{\circ}C$부터 증가하기 시작하였다. 인산 쌀 전분의 색도는 원료 전분에 비하여 명도가 감소하였으며, 적색도 및 황색도는 증가하였다. 이것은 초산 처리 쌀 전분보다는 색상에서 좋지 않게 평가되었다. 인산 처리한 추청벼 및 삼강벼 전분의 호화개시 온도는 각각 5$0^{\circ}C$, 53$^{\circ}C$로서 인산 처리에 의해 원료 쌀 전분보다 14~15$^{\circ}C$ 낮아졌으며, 인산 쌀전분의 점도는 원료 쌀 전분에 비하여 7.4~8.4배 증가하였고 추청벼 전분이 삼강벼 전분보다 높게 나타났다. 인산 쌀 전분 겔의 견고성, 응집성, 접착성, 탄력성, 점착성 및 씹힘성은 원료 전분 겔보다 높았으며 두 품종간에는 추청벼 전분이 다소 높았다. 인산 쌀 전분 입자의 표면 구조는 원료 쌀 전분에 비하여 다소 팽윤되어 헝클어진 형태를 나타냈다. 이상의 결과를 볼 때 인산 처리 쌀전분이 원료 쌀 전분보다 호하 개시 온도가 낮고, 점도가 높아 즉석면의 제조 시 호화 온도를 낮추고 쫄깃쫄깃한 촉감의 면을 만들 수 있음을 시사하고 있으며, 정이 보고한 초산 처리 쌀 전분과 이용성을 비교할 때 인산 처리 전분이 라면 제조에 있어 더 효과적일 것임이 예상된다.desirability(전체적으로 바람직한 정도)의 경우 효소처리시킨 시료중 pH6.5$\longrightarrow$3.5, 35$^{\circ}C$(T1)과 45$^{\circ}C$(T3)처리군이 28일간 수침시켜 제조한 유과와 비교될 만한 높은 점수를 보여 이를 처리군에서 바람직한 특성을 지닌 유과 제조가 가능한 것으로 나타났다.의 Softness 는 Compression force 및 Work ratio 와 유의적인 상관관계를 나타내었으며, Dryness 와 Crumblyness 는 Work ratio와 유의적인 상관관계를 나타내고 있어 백편의 조직감은 Compression force 와 Work ratio로 대치할 수 있을 것이라고 사료된다. 수분함량은 기계적 검사보다 관능검사와 더욱 높은 상관관계를 나타냈다.내었다. 항균활성이 우수한 생약재를 농도별로 활성을 조사한 결과, 물 추출물과 10% Ethanol 추출물 모두 낮은 농도에서도 우수한 항균활성을 나타내었다.취와 함께 점질성 갈변물질이 생성되었다. 이와 같은 결과로 볼 때, BAAG의 처리는 BAAC의 경우보다 가격은 저렴하면서도 항균력은 우수한 천연 항균복합제재로써 농산물 식품원료에 적용하여 선도유지 기간을 연장할 수 있는 효과를 기대할 수 있었다. 과일 등의 포장제로서 이용할 가능성을 확인하였다.로 [-wh] 겹의문사는 복수 의미를 지닐 수 없 다. 그러면 단수 의미는 어떻게 생성되는가\ulcorner 본 논문에서는 표면적 형태에도 불구하고 [-wh]의미의 겹의문사는 병렬적 관계의 합성어가 아니라 내부구조를 지니지 않은 단순한 단어(minimal $X^{0}$ elements)로 가정한다. 즉, [+wh] 의미의 겹의문사는 동일한 구성요

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.9
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• pp.1300-1306
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• 2011

This study investigated the physicochemical characteristics of wet-milled rice flour treated with pectinase and cellulase in a steeping process. Enzyme treatments were used as follows: pectinase 0.05%, cellulase 0.05%, and mixed enzyme treatments 0.05~0.2%. For particle distribution, rice flour E-treated with mixed enzymes (pectinase 0.05% and cellulase 0.05%) was the finest at 48.3% particle distribution less than $53\;{\mu}m$. Protein contents and damaged starch were reduced by enzyme treatments. Damaged starch was the lowest (12.1%) in rice flour E compared with non-enzyme treatment (18.1%). Amylose content, water binding capacity, solubility, and swelling power all increased upon enzyme treatments, and their effects increased upon mixed enzyme treatment. For gelatinization characteristics of RVA, peak viscosity, final viscosity, breakdown, and total setback viscosity increased in rice flours treated with mixed enzymes. Especially, in steeping method with mixed enzyme treatment, pectinase 0.05% and cellulase 0.05% treatment was suitable for minimizing damaged starch and high fine particle distribution of rice flours compared with single enzyme treatment.

• Journal of the Korean Recycled Construction Resources Institute
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• v.4 no.4
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• pp.463-469
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• 2016

In this paper, compressive strength and water permeability performance for two types of crack self-healing materials such as SH-PO-0 composed of mineral admixtures(expansive agent, swelling material and crystal growth agent) and SH-PO-(5, 15, 30) blended with SH-PO-0 and phosphate additive(PO) dissolving easily calcium ion, were evaluated. The test results show that the water flow of SH-PO-0 decreased steeply at the early age although compressive strength decreased about 9% at 28 days compared with OPC. The higher PO replacement ratio is, the lower compressive strength and more improved water permeability performance is, and thus, based on such results, adequate PO replacement ratio is 15%. It is also found that the self-healing performance of SH-PO-15 was quite improved at the early ages and however, the performance of SH-PO-15 is similar to one of SH-PO-0 at long-term ages, and 28 days compressive strength of SH-PO-15 decreased about 8% compared with SH-PO-0. In addition, it is confirmed from the analysis of SEM-EDS that calcium ions of SH-PO-15 were crystallized more than those of SH-PO-0.

• Journal of the Korean Ceramic Society
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• v.38 no.11
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• pp.1067-1074
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• 2001

Four different composition of autoxidation drying type waterborne coatings (WBC-1, WBC-2, WBC-3, WBC-4) were prepared by the compounding of bentonite (BEN) as a water swellable clay and organometallic soaps as a drier with acrylic binder and coating additives. The solution viscosity, solid content, rheological properties and drying rate of WBCs were investigated. Also the thermal stability, the transmittance and the water-resistance of the films casted by WBCs were measured, and the surface topology of WBC films were investigated by the scanning probe microscopy. As WBC-2, WBC-3 and WBC-4 containing BEN showed the thixotropy with the shear rate, the storage stability of WBC was a excellent. When the driers was mixed in the ratio of Mn/Zn/Ba=1/2/3, the dry ability of WBCs showed maximum as 5.0 sec at 60$\^{C}$. The initial decomposition temperature and the transmittance of WBC films containing BEN increased in range of 32.2∼54.7$\^{C}$ and 5.1∼8.6% than the commercial WBC (MC-21W), respectively. The water resistance of WBC films increased in order of MC-21W

• Journal of the Korean Geosynthetics Society
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• v.19 no.1
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• pp.25-33
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• 2020

To improvement the swelling characteristics of the existing cutoff wall against the moisture, the permeability of the sand, calcium bentonite and solidifier mixture according to the contact with trichloroethylene (TCE) was evaluated. Characteristics analysis and the permeability test of the research materials were performed. The permeability was decreased as the mixing ratio of the calcium bentonite was increased and it was increased as the mixing ratio of the solidifier was increased. In conclusion, when mixing 15% of calcium bentonite and more than 30% of solidifier, the permeability coefficient in the underground water movement was analyzed as more than α × 10^-4 cm/sec showing that it does not block the underground water movement. In addition, as the permeability coefficient of mixtures after TCE reaction was analyzed as less than α ×10^-7 cm/sec, it satisfied the condition of blocking layer (less than 1.0 × 10^-6 cm/sec). Therefore, the calcium bentonite and solidifier can be utilized as barrier that showing the characteristic of percolation ability conversion in soil and underground water contaminated with TCE.

• Clean Technology
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• v.18 no.1
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• pp.57-62
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• 2012

Aqueous poly (vinyl alcohol) (PVA) solution was modified by using hydrophobic vinyltriethoxysilane (VTEOS) and then adding different amounts of poly (acrylic acid) (PAA) to the resulting solution. Thermal and mechanical properties, contact angle, water vapor transmission rate (MVTR) and oxygen gas transmission rate ($O_2TR$) of the film samples fabricated by these solutions were investigated. The glass transition temperature (Tg) of the VTEOS-modified films was sightly increased and the value remained unchanged according to the amount of PAA. The tensile strength of the VTEOS-modified films was found to be 9.48~10.72 $kg/mm^2$ which showed no significant difference compared with that of PVA. The film prepared with VTEOS-modified PVA/PAA (= 90/10), of which the swelling and solubility were measured to be 198% and 0%, respectively, showed improved water-resistance. The MVTR and $O_2TR$ for the PET film (thickness 50 ${\mu}m$) coated with VTEOS-modified PVA/PAA (= 90/10) film (thickness 2.5 ${\mu}m$) were measured to be 11.04 $g/m^2/day$ and 3.1 $cc/m^2/day$, respectively.