This study was done to develop the standard recipe for nutritious cowpea starch based grape jelly. The effects of grape juice concentration (4, 8, 12%) and 0.2% calcium addition were evaluated on textural and sensory properties of grape jelly through the instrumental analysis using rheometer and sensory evaluation. Instrumental analysis showed that hardness, chewiness and gumminess of grape jelly was incerased significantly In jelly made of higher concentration of grape juice, and also in 0.2% calcium containing jelly. According to sensory evaluation, higher grape juice contains jelly showed advantages in preference of color and overall quality. Calcium addition increased sourness in sensory score. Overall, 12% grape juice and 0.2% calcium containing jelly was most preferable, which means calcium fortified cowpea starch based grape jelly was successful try for nutritious and practical food for elementary school foodservice.
A fermented squeezed-type paste was processed in order to highly effective utilization of cockle shell by-product, and improvement on rheological properties and texture of hydrolysate by used additives. The cockle shell by-products were homogenized with addition of water and enzymatically hydrolyzed at 50℃ for 8 hours adde`d 4% Protease N. P.(Pacific Chemical Co.). And the hydrolysate was thermally treated for the purpose of flavor improvement, enzyme inactivation and pasteurization product at 100℃ for 1 hour, with 4% glucose. To make improvement of rheological properties, used complex additive with 0.5% alginic acid, 1% pectin and 0.2% agar were very effective. And stability of mixing was 98.1% after centrifuged at 10, 000 rpm for 60 minutes. The chemical composition of moisture, total carbohydrate, total nitrogen and amino type nitrogen in the fermented squeeze-type cockle shell by-product paste were 57.7%, 20.6%, 1, 458㎎% and 1, 187㎎%, respectively. And the ratio of amino type nitrogen in total nitrogen was 81.4%.
The modification of rice powder was attempted by treatment of acetic acid and epichlorohydrin to improve the functional properties of baby food. The initial gelatinization temperature of rice powder determined by amylograph was decreased from 79.5℃ to 63℃ by modification. The apparent and maxium viscosity of rice paste at 95℃ before and after modification were increased from 92B.U. to 236B.U. and from 100B.U. to 202B.U., respectively. The light transmittance of modified rice paste was increased from the temperature of 60℃ and by increasing the degree of substitution at the fixed temperature, while decrease more or less by the treatment of epichlorohydrin. The degree of retrogradation of the paste was decreased from 28.7 to 18.0 upon modification. The rate of syneresis of modified rice powder was decreased with increasing the drgree of substitution and ,the extend of epichlorohydrin treatment. Syneresis was not observed when acetylated rice powder whose DS value is 0.048 was treated with 0.25% of epichlorohydrin for the formation of cross-linkage. The addition of modified rice powder in preparation of semi-solid type infant food could improve the quality without lowering overall digestibility.
Starch plays an important role in textural quality of infant food which is mainly affected by retrogradation of starch during storage. The acetylated rice was prepared and its physicochemical properties were evaluated to improve the textural quality of infant food when added. When the rice powder was reacted with acetic acid with its increasing concentration from 0.1 M, 0.2 M to 0.3 M, the amount of acetyl group and degree of substitution were increased by 0.39%, 0.8% and 1.27%, and by 0.0014, 0.031 and 0.048, respectively. The initial gelatinization temperature of rice paste determined by amylograph was decreased from 79.5℃ of unmodified rice to 67.5℃ of acetylated rice whose DS is 0.048. The apparent and maxium viscosity of rice paste at 95℃ before and after modification were increased from 92 B.U. to 201 B.U. and from 100 B.U. to 236 B.U., respectively, The degree of retrogradation and rate of syneresis were decreased from 28.7 to 18.8 and from 0.47% to 0.25%, respectively with increased by DS from 0 to 0.048. The digestibility rate of rice powder decreased from 9.19 of natural rice powder to 7.54 of acetylated rice powder whose DS is 0.048. In United State, there is no serious problem in total digestibility because only 4% of modified rice powder is added in production of infant food.
자색고구마 분말을 0∼5%를 첨가하여 호상 요구르트를 제조하여 요구르트의 품질 및 기호성에 미치는 영향을 검토한 결과는 다음과 같다. 자색고구마첨가에 의해 산도, 당도, 유산균수가 대조구에 비해 높게 나타났으며 요구르트의 색택은 자색고구마 첨가량이 많을수록 lightness와 yellowness는 감소되고 redness는 증가하면서 점도는 크게 상승하였다. 요구르트의 관능성을 보면 조직감과 색은 대조구보다 첨가구에서 양호했으며 맛에서는 차이가 없었고 전체적인 기호도는 자색고구마 3∼4% 첨가구에서 가장 우수하였다.
Engine valve-shaped TiAl-Mn intermetallics containing 43.5 to 47.5at%Al (Mn/Al=0.036) are successively fabricated by reactive sintering the elemental powder mixtures near-net shaped by extrusion and die forging. A duplex structure consisted of lamellar grains and equiaxed grains is developed for all compositions, and the areal fraction of the lamellar grains(or equiaxed grains) decreases (or increases) with increasing Al content. As Al content increased, the elongation increases with accompanying decrease in yield strength and ultimate tensile strength at both room temperature and 80. This indicates that the suitable composition is Ti-45at%Al-1.6at%Mn in considering the balance of ambient and elevated tensile properties. The reactive-sintered Ti-45Al-1.6Mn alloy shows superior oxidation resistance not only to the plasma arc melted one but also to the heat resistance steel STR35(representative exhaust valve head material for automotive engine). The reactive-sintered Ti-45Al-1.6Mn alloy coated with an oxidizing scale exhibits a better wear resistance than induction hardened martensitic steel STR11(representative exhaust valve tip material for automotive engine).
Low foaming acidic degreasing agent(LFADAs) were prepared by blending sorbitol, n-octanoic acid, MJU-100A, Tetronix T-701, Na-dioctyl sulfosuccinate, Demol C, and phosphoric acid. The physical properties of LFADAs tested with aluminum specimen showed the following results ; when 3wt% LFADA-6 was performed at 70℃, the degreasing rate was 95% which is comparitively good, and the percentage of etching was 0.275% which was found to be less than that of commercialized product. When 20wt% of LFADA-6 was added at 65℃, the percentage of derusting was 92% and the good defoaming effect proved by following low foaming power tests respectively : Ross and Miles, and Ross and Clark methods.
Low toxic concentrated oil dispersant using n-Paraffin and Di(ethylene glycol)mono butylether mixed solvent was prepared, and tested by oil dispersant performance test method, and oil dispersant efficiency was measured using vertical shaking method to 3 kinds of Crude oil, Bunker oil and W/O emulsions with different physical properties by appling the prepared dispersant. Although toxicity test was performed with Flat fish and Rock fish by appling the mixed oils emulsified using prepared oil dispersant, couldn't find the toxicity to them. Concentrated oil dispersant prepared has a good dispersion efficiency of 97.2% after 0.5min settling time and 28.3% after 10min settling time to Bunker B oil with 10% water solution. Especially, the concentrated oil dispersant showing the low toxicity to Oryzias Latipes(24hr, TLm) was 54,000 ppm and to Brine Shrimp Artemia(24hr, TLm) was 51,000ppm, and also, it was completely biodegradated to 99.1% after 7~8days.
Vacuum Hot Pressing을 이용하여 제조한 TiNi형상기억섬유 강화 6061 AI기지 복합재료를 제조하고 미세조직 및 기계적 특성 등을 연구하였다. 제조된 복합재의 항복응력은 예비변형량, 섬유체적율 및 열처리에 따라 증가하였다. 복합재의 지적특성은 예비변형이 가하여진 후 재가열되었을 때 기지 내 TiNi 섬유의 형상기억효과에 의한 압축잔류응력 발생에 기인된다. 미세조직 관찰 섬유와 기지 사이에는 AI3Ti및 AI3Ni의 금속간화합물층이 관찰되었다. 또한 시험온도 증가와 더불어 TiNi섬유강화된 복합재의 유동강도는 높은 값을 나타내었다.
The establishment of optimal producing condition for rice-based infant foods using modified rice powder was attempted. The modification of rice powder was prepared by microwave heating as well as partial enzymatic hydrolysis. Not only thermal treatment but also enzymatic hydrolysis on rice powder increased D.E. value from 1.25 to 3.81. The water binding capacity, swelling power, solubility, digestibility by α-amylase, light transparency, and paste clarity of the modified rice powder compared to unmodified rice powder were increased from 107% to 249%, from 7.80 to 42.52, from 0.04% to 0.89ft, from 9.19% to 23.01, from 33% to 42%, and from 2.2% to 3.9%, respectively. On the other hand, gelatinization temperature, apparent viscosity, and degree of retrogradation of modified rice powder showed negative correlation with D.E. value. The 「results suggested that the thermal and enzymatic treatment on rice powder improved the physicochemical properties of rice based infant food by enhancing carbohydrate absorptionability and lowering the viscosity and opacity.
토양 유기물에서 생물학적 난분해성인 부식물질을 알카리에서 추출하고 산성영역에서 침전되는 성분인 부식산을 정제, 추출하였다. 부식산의 주성분인 카르복실기가 이온교환 능력을 가지고 있는 것을 이용하여 PVA와의 불균질한 이온교환막을 제조하여 생리활성 이온인 K+, Na+의 이동 및 이동속도를 검토하여 보았다. 그 결과 수소이온 농도가 높을수록 이동속도는 빠르게 나타나고, 특히 10-1,100영역에서 급격한 변화를 보였다. 또한 K+, Na+의 농도가 증가함에 따라 그 선택성이 나타났으며, 특히 수소이온농도 100 일때는K+이 2배정도 빠르게 이동되고 있다. 따라서 이러한 생리활성 이온의 선택성 및 이동속도의 향상으로 부식산이 이온교환막의 새로운 재료로서의 그 가능성을 나타내었다.
이규화몰리브덴 고온발열체의 제조공정을 개발하였다. 원료분말은 상용 MoSi2분말이었으며 Bentonite, Si3N4, B, ThO2를 각각 가소제와 첨가제로 사용하였다. 이들은 진공압출, 소결, 단자부 기계가공, U자형 성형, 용접 등의 과정을 거쳐 U자형 발열체로 제조되었다. 사용제품의 분석결과 최근 사용온도가 크게 증가된 것으로 알려진 1900˚C용 발열체는 다량(33wt%)의 W이 Mo을 치환하고 있는 것으로 나타났다. 발열체의 전기비저항은 겉보기 밀도가 증가함에 따라 급격하게 감소하는 경향을 보였으며 첨가물들의 영향은 미미하였다. 1400-1600˚C에서 용접한 경우 용접면에서의 전기비저항은 비용접부보다 낮았으며 용접온도가 증사함에 따라 감소하였다. 발열시험결과 제조된 발열체는 표면온도가 1700˚C이하에서는 문제가 없었으며 1750˚C 이상의 온도에서는 원형의 융기가 표면에 발생하면서 급속하게 파괴되었다. 이 융기는 X-선 회절분석결과 SiO로 밝혀졌으며 따라서 발열체의 파괴는 MoSi2/SiO2계면에서의 Si(in MoSi2) + SiO2=2SiO(g)반응에 으해 일어나는 것으로 판단된다.