• Korean Chemical Engineering Research
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• 제46권2호
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• pp.274-278
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• 2008

실란커플링제인 glycidoxypropyl trimethoxysilane(GPTMS)과 methacryloxypropyl trimethoxysilane(MPTMS)을 10:0, 9:1, 7:3, 5:5, 3:7, 0:10의 다양한 몰 비로 혼합한 용액으로부터 sol-gel법을 이용하여 하드 코팅 용액을 제조하였다. 제조된 코팅 용액을 polycarbonate(PC) 시트 위에 스핀 코팅 시키고, $130^{\circ}C$에서 3 h 동안 열 경화시켜 하드 코팅 막을 제조 하였다. 이 과정 중 코팅 용액 중의 GPTMS와 MPTMS의 몰 비 변화가 코팅 막의 물성에 미치는 영향을 살펴보았다. GPTMS와 MPTMS가 5:5의 몰 비로 제조된 코팅 용액으로 PC 시트 위에 코팅한 경우가 다른 조건으로 제조된 코팅 용액보다 우수한 연필경도 및 기재와의 부착력을 보였다. 또한 코팅 용액 중의 $H_2O$의 첨가량이 증가할수록 코팅막의 연필경도는 증가하였다.

• 한국의류산업학회지
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• 제20권4호
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• pp.422-428
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• 2018

In this study, we developed honeycomb pads using foam and polymer gel and verified the impact protection performance of pads for the development of a fall protection pants for elderly women aged 65 and over who have a high risk of fracture due to falls. The results are as follows; In the first experiment, the impact protection performance was evaluated for four honeycomb pad samples (CR foam, EPDM foam, hardness 15 polymer gel, and hardness 30 polymer gel) manufactured to a thickness of 5 mm using a single material. When the force of about 10757N was applied to the specimens, all four pads reduced the impact force to 3100N or less. Polymer gels showed better protection than foam materials. In the second experiment, the thickness of the protective pad was set to 8 mm in order to improve the shock absorbing performance of the protective pad. As a result of evaluating the impact protection performance of the foam single pad and foam gel composite pad, the impact absorbing performance of the foam single pad was better. Finally, four kinds of protection pads were made by assigning the foam single pad and the foam gel composite pad to pants type and underwear type respectively. The pad thickness of the main protection area was set to 8 mm to enhance the protection, and gradually decreased to 5mm and 3mm toward the edge to improve the appearance and fit.

• 한국치위생학회지
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• 제12권1호
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• pp.113-122
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• 2012

Objectives : This study was carried out to investigate the caries resistant effect of fluoride by dental polishing prior to fluoride application in vitro. Methods : Artificial caries lesion was made on the surface of specimen enamel taken from cow's permanent cuspid on the part of labial surface after resin embedding and polishing. Artificial dental plaque was formed on the 72 dental specimen 25~45 VHN(Vickers Hardness Number) which were divided into three groups(fluoride varnish, APF gel, control) with dental polishing and without polishing respectively. Fluoride varnish and APF gel group with 20 second polishing or without polishing were immersed in the artificial saliva respectively. Control group with or without polishing were immersed in the artificial saliva. Results : 1. Significant difference was not found by fluoride varnish between polishing group and non polishing group (p>0.01). 1) polishing group. The changes of Vickers Hardness Number(VHN) were $14.49{\pm}13.73$. 2) non-polishing group. The changes of VHN were $11.67{\pm}5.39$. 2. Significant difference was not found by APF gel between polishing group and non polishing group (p>0.01). 1) polishing group. The changes of VHN were $8.48{\pm}8.37$. 2) non-polishing group. The changes of VHN were $5.32{\pm}2.59$. Conclusions : Showed no significant difference between polishing group and non-polishing group regardless of fluoride materials (fluoride varnish, APF gel).

• 한국가금학회지
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• 제17권3호
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• pp.211-216
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• 1990

난백단백질의 농도와 당류의 첨가수준이 난백의 열안정성에 미치는 영향을 검토하기 위하여 가열처리($120^{\circ}C$, 30분 또는 $90^{\circ}C$, 30분) 전후 난백겔의 조직감 및 색택을 측정하였으며 그 결과는 다음과 같다. 난백단백질의 농도가 낮아짐에 따라 난백겔의 경도는 열처리 조건에 상관없이 급격히 덜어졌으며 명도와 황색도는 점차 감소하였다. 응집성은 단백질 농도가 $8.3^{\circ}C$ 이하로 희석됨에 따라 증가하기 시작하였다. Sucrose 2.5%의 첨가로 난백겔의 경도가 다소 증가하였으나 그 이상 원가로 점차 저하하였으며 sucrose의 첨가로 응집성은 다소 저하하였다. Glucose의 첨가에 의해 고온처리 시 난백의 응집성은 다소 증진되었으나 명도가 감소하고 황색도는 저온처리의 경우에도 고온처리와 같이 높아졌다.

• 한국식품조리과학회지
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• 제19권4호
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• pp.511-520
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• 2003

This study was carried out to determine the effects of various contents of kiwifruit contents on the quality characteristics of mixed polysaccharide gels made from $\kappa$-carrageenan and locust bean gum. The color value, gelling temperature, melting temperature, break down rate, syneresis, rupture properties, TPA properties and sensory properties of mixed polysaccharide gels with various contents of kiwifruit contents were measured. As the kiwifruit contents was increased, the lightness (L), yellowness (b) and greenness (-a) of the mixed polysaccharide gels increased. There were no differences in the color values of gels during storage. As the kiwifruit content was increased, the gelling and melting temperatures of the mixed polysaccharide gels also increased. The mixed polysaccharide gels with high kiwifruit contents were difficult to melt, and it seemed that the addition of kiwifruit to the mixed polysaccharide gels could improve the thennal stability of the gels. The syneresis of the gel increased with increasing storage time, whereas the addition of kiwifruit to the gel resulted in suppression of syneresis. With regard to the rupture properties, stress, energy and strain, they were all decreased with increasing kiwifruit contents. The TPA properties, adhesiveness, hardness and chewiness increased and cohesiveness decreased with increasing kiwifruit contents. The results showed that the gel became tough and adhesive, and could be easily broken under small deformation, with increasing kiwifruit contents. The sensory evaluation showed that the green color, aroma, sweetness and sourness increased with increasing kiwifruit contents. The texture, adhesiveness, springiness and cohesiveness decreased, and brittleness and hardness increased, with increasing kiwifruit contents. The overall acceptability of the gel with 30% kiwifruit content was the highest. Thus, mixed polysaccharide gels made from kiwifruits could be useful, as the addition of kiwifruit to a mixed polysaccharide gel results in a good aroma, taste and stability, despite a lowering of the textural properties.

• 한국식품조리과학회지
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• 제18권3호
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• pp.275-279
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• 2002

동부 묵가루 제조 방법과 대두유 첨가량과 소금의 첨가 유무를 달리한 묵을 제조하여 기계적인 texture특성을 측정하고, 관능검사를 실시하여 대두유와 소금의 첨가가 묵의 품질특성에 미치는 영향을 검토한 결과를 요약하면 다음과 같다. 1. 소금의 첨가유무에 관계없이 대두유의 첨가량이 많을수록 hardness, chewiness는 전반적으로 감소하는 경향이었으나, cohesiveness, springiness는 대두유 첨가량에 따라 큰 차이가 없었다. 시판 묵가루를 이용하여 만든 묵이 실험실 제조 묵가루를 이용한 묵보다 hardness는 높았고, cohesiveness는 낮았으며, springiness, chewiness는 큰 차이를 나타내지 않았다. 2. 관능검사 결과 대두유를 첨가할수록 노르스름하고, 불투명하며, 느끼하고, 부드럽게 평가되었으나, 전반적인 바람직성에서는 바람직하지 않은것으로 평가되었다. 그러나 소금을 첨가하였을 경우 소금을 첨가하지 않은 시료보다 대두유 첨가량에 따른 차이가 적었으므로 묵 제조 시 대두유와 소금을 첨가하여 부드러우며, 기본적인 간을 나타내는 묵을 만들 수 있을 것으로 생각된다.

• 한국식품영양학회지
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• 제20권4호
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• pp.399-405
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• 2007

The quality characteristics of breads made by adding levels of 30%, 60%, and 100% aloe gel were investigated. The 60% aloe gel sample had a larger dough volume than the control dough. Also, the loaf volume and specific volume of the bread made with 60% aloe gel were larger than those of the control bread. The pasting temperature increased gradually with the increasing amounts of substituted aloe gel as compared to wheat flour with water added$(66.5{\pm}12^{\circ}C)$; the wheat flour with 100% aloe gel had a pasting temperature of $90.7{\pm}1.1^{\circ}C$. Peak viscosity decreased gradually with increasing amounts of aloe gel when compared to the wheat flour with water added. Setback also was decreased gradually with the increasing amounts of aloe gel as compared to the wheat flour with added water. From the setback decrease it is suggested that the aloe controlled retrogradation of the bread during short-term storage. The crumb color of the bread made with the aloe gel was not significantly different to that of the control bread, and the color of the crumb was yellow-white. Bread hardness decreased gradually with increasing amounts of the substituted aloe gel. However, bread gumminess and chewiness increased gradually with increasing amounts of aloe gel. The springiness of the bread made with 100% aloe gel was lower than that of the control bread. With regard to flavor and taste, the bread made with 100% aloe gel produced a green-like odor and had a bitter taste. The mouth feel of the breads made with aloe gel was considered soft and moist. The overall acceptabilities of the breads made with 30% and 60% aloe gel were not significantly different from the control bread, but the bread made with 100% aloe gel had a green smell and bitter taste. Yet accordingly, the results indicate that functional and health products with improved quality could be developed by adding aloe gel to breads and cakes.

• Food Quality and Culture
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• 제3권2호
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• pp.53-58
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• 2009

This study was conducted to investigate the quality characteristics of frozen stored mungbean starch gels added with sucrose fatty acid ester (SE). The study showed a delay of gelatinization of mungbean starch by SE addition through the measurements conducted by using Rapid Visco Analyzer (RVA) and Differential Scanning Calorimeter (DSC). In the color of SE added frozen stored gels, lightness (L) and yellowness (b) values were increased compared to those of values measured from freshly prepared gel, whereas redness (a) value was decreased. The addition of 1% SE on mungbean starch gel prevented the color change during frozen storage. Rupture stress and rupture energy of frozen stored gel was higher than those of freshly prepared gel, whereas rupture strain of frozen stored gel was lower than that of freshly prepared gel. The addition of 1% SE on mungbean starch gel prevented the change of rupture characteristics during frozen storage. Texture profile analysis(TPA) characteristics revealed a significant change of the gel texture during frozen storage by showing an increase of hardness of the frozen stored gels compared to the freshly prepared gels with newly discovered fracturability, which resulted to show a large difference of gel texture by showing the disappearance of adhesiveness and large reduction of cohesivenes. The addition of 1% SE on mungbean starch gel prevented the change of TPA characteristics during frozen storage. Scanning electron micrographs showed that network structure of frozen stored gel was more rough than that of freshly prepared gel, and the addition of 1% SE on mungbean starch gel could suppress the breakdown of network structure. Thus the addition of 1.0% SE on mungbean starch gel was appropriate method for remaining gel characteristics during frozen storage.

• 한국식품영양학회지
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• 제16권2호
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• pp.105-110
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• 2003

밥의 식미에 영향을 주는 쌀품종별 노화특성에 관한 연구에서 아밀로오스 함량과 gel consistency가 다른 5가지 품종에 대하여 조사하였다. Brabender amylograph에 의한 쌀품종별 호화특성에서는 아밀로오스 함량에 관계없이 hard gel인 품종이 높은 setback 값을 보였다. 저장시의 경도변화에서는 아밀로오스 함량이 높은 품종의 최종경도가 더 높았다. 또한 Avrami equation에 의한 쌀전분겔의 노화특성 연구에서도 아밀로오스 함량이 높은 품종에서 노화속도를 나타내는 지표로서 사용되는 time constant(l/k)값이 더 높은 것으로 나타남에 따라 아밀로오스 함량이 쌀전분의 노화현상에서 매우 중요한 요인라는 것을 알 수 있었다.

• Food Science and Biotechnology
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• 제14권1호
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• pp.11-15
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• 2005

Dynamic shear moduli of isolated soy protein solutions upon heating were measured to monitor gelation. Onsets of gelation coincide with onset temperatures of denaturation in glycinin and ${\beta}$-conglycinin solutions, whereas in isolated soy proteins, onset of gelation was above denaturation temperature of ${\beta}$-conglycinin with storage modulus increasing in two steps. The first increase in storage modulus of isolated soy proteins occurred at about $78.5^{\circ}C$, while the second increase started at about $93^{\circ}C$. Gel properties of soy protein gels having different proportions of glycinin and ${\beta}$-conglycinin were measured by compression-decompression test. ${\beta}$-conglycinin was responsible for gel elasticity. Glycinin significantly increased hardness, toughness, and fracturability of gels at high heating temperature near $100^{\circ}C$. Results reveal texture of soy protein gels can be controlled by regulating ratio of glycinin to ${\beta}$-conglycinin and heating temperature.