• 한국식품과학회지
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• 제17권5호
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• pp.345-349
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• 1985

$3^{3}$ 요인배치법에 의하여, 농도 저장시간 저장온도의 차이에 따를 도토리묵의 물리적 특성 변화를, Instron Universal Testing Machine을 사용하여 측정 비교하였다. 도토리묵의TPA curve는 첫 번째 압착에서 두개의 peak를 보이고, negative peak는 나타나지 않았다. 견고성과 절단성은 농도 저장시간 저장온도의 세 인자들의 변화에 대해 매우 유의적인 차이를 보이고, 두 peak의 높이 차이는 농도와 저장온도의 변화에 의해 특히 영향을 받으며 저장시간의 효과도 무시할 수 없었다. Bend는 농도의 변화에 대해서는 민감하게 대응하나 저장온도의 영향은 다소 약하게 작용하며 저장시간에 따른 변화는 무시할 수 있었다. 탄성은 농도의 변화에 대해서만 유의적인 차이를 보였다.

• 한국식품과학회지
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• 제18권3호
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• pp.215-220
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• 1986

리오메타 또는 회전점도계를 사용하여 $9{\sim}30%$ 쌀보리와 겉보리전분 젤의 역학적 성질을 조사하였다. 20 및 30% 보리전분젤의 압축파괴특성은 $0{\sim}2\;kg$의 하중하에서 탄성, 소성 및 파괴의 3영역을 포함한 변형을 나타내었다. 압축응력완화 곡선은 시료전분젤의 점탄성이 2개의 Maxwell 모형을 병렬로 연결한 4요소역학 모형으로 설명할 수 있음을 보였다. 또 9% 전분젤에 대한 정상전단하의 응력완화는 선형점탄성 이론으로 설명할 수 있었으며 이들 응력완화과정은 전분젤의 구조에 미치는 온도 또는 첨가제영향의 검토에 유효한 것으로 시사되었다.

• 산업식품공학
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• 제21권1호
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• pp.36-41
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• 2017

The release profiles of nisin from nisin-incorporating gel foods and the antimicrobial activities of the gels on the growth of Brochothrix thermosphacta in an aqueous system containing the gels have been investigated. A linear regression model was applied to determine the diffusion coefficient (D) for the diffusion of nisin in the gel. The antimicrobial activities of nisin released from 1, 2 and 3% (w/v) agar gels on the growth of B. thermosphacta in a broth medium with and without nisin were investigated. The D decreased from $1.2{\times}10^{-2}$ to $8.2{\times}10^{-3}$ and $6.4{\times}10^{-3}cm^2/s$ as the agar concentration in the gel increased from 1 to 2 and 3% (w/v), demonstrating the diffusion rate in the gels can be controlled by the agar concentration in gel. The agar gel incorporating nisin inhibited the B. thermosphacta growth in the broth medium by prolonging the lag phase. The growth inhibition was enhanced by the addition of nisin in the medium. The results of this study exhibited that the gel food is a feasible nisin delivery system with a controlled release achieved by the adjustment of agar concentration in the system, demonstrating the potential of nisin-incorporating gel for preserving particulate-containing drinks.

• 한국축산식품학회지
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• 제39권4호
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• pp.576-584
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• 2019

This study was performed to evaluate the physicochemical properties of myofibrillar protein (MP) gels containing pork skin gelatin at different salt concentrations. MP gels were prepared to the different salt levels (0.15, 0.30, and 0.45 M) with or without 1.0% of pork skin gelatin. Cooking yield (CY), gel strength, shear stress were measured to determine the physical properties, and SDS-polyacrylamide gel electrophoresis, scanning electron microscopy, fourier transform infrared spectroscopy, sulfhydryl group and protein surface hydrophobicity was performed to figure out the structural changes among the proteins. The addition of gelatin into MP increased CYs and shear stress. MP at 0.45 M salt level had the highest CY and shear stress, as compared to MPs at lower salt concentrations. As the salt concentration of MP gels increased, the microstructure became the compact and wet structures, and decreased the amount of ${\alpha}-helix$/unordered structures and ${\beta}-sheet$. MP with gelatin showed a decreased amount of ${\alpha}-helix$/unordered structures and ${\beta}-sheet$ compared to MP without gelatin. The addition of gelatin to MP did not affect the sulfhydryl group, but the sulfhydryl group decreased as increased salt levels. MP mixtures containing gelatin showed a higher hydrophobicity value than those without gelatin, regardless of salt concentration. Based on these results, the addition of gelatin increased viscosity of raw meat batter and CY of MP gels for the application to low salt meat products.

• Bulletin of the Korean Chemical Society
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• 제4권4호
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• pp.162-169
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• 1983

The swelling and stress-elongation experiments have been performed for two kinds of gels of tactic poly (2-hydroxyethyl methacrylate) (P-HEMA) with varying crosslinker concentrations. The gels of isotactic and syndiotactic P-HEMA were swollen in aqueous salt solutions upon varying molal concentrations. The solute used were NaCl, $MgCl_2$, $Na_2SO_4$, $MgSO_4$ and urea. The water content at equilibrium swelling and the salt partition coefficient were determined, and stress-elongation curves of the gels were obtained. From these results, the effective number of chain (${\nu}_e$) and the Flory-Huggins interaction parameter (${\chi}_1$) were also obtained. The swelling experiment was also performed under varying solvents, and the degree of swelling was determined. The solubility parameter of P-HEMA was obtained as 13.4 (cal/mole)$^{l/2}$ using the correlation between the degree of swelling and the solubility parameter (${\delta}_1$) of solvents. The mechanical properties of syndiotactic P-HEMA is stronger than that of isotactic P-HEMA, and the water content of both gels become smaller when the crosslinking increases. Isotactic P-HEMA contains more water content than syndiotactic P-HEMA does.

• Biomolecules & Therapeutics
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• 제19권3호
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• pp.357-363
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• 2011

In relieving local pains, ropivacaine has been widely used. In case of their application such as ointments and creams, it is difficult to expect their effects for a significant period of time, because they are easily removed by wetting, movement and contacting. Therefore, the new formulations that have suitable bioadhesion were needed to enhance local anesthetic effects. The effect of drug concentration and temperature on drug release was studied from the prepared 1.5% Carboxymethyl cellulose (CMC) (150MC) gels using synthetic cellulose membrane at $37{\pm}0.5^{\circ}C$. As the drug concentration and temperature increased, the drug release increased. A linear relationship was observed between the logarithm of the permeability coefficient and the reciprocal temperature. The activation energy of drug permeation was 3.16 kcal/mol for a 1.5% loading dose. To increase the skin permeation of ropivacaine from CMC gel, enhancers such as saturated and unsaturated fatty acids, pyrrolidones, propylene glycol derivatives, glycerides, and non-ionic surfactants were incorporated into the ropivacaine-CMC gels. Among the enhancers used, polyoxyethylene 2-oleyl ether showed the highest enhancing effects. For the efficacy study, the anesthetic action of the formulated ropivacaine gel containing an enhancer and vasoconstrictor was evaluated with the tail-flick analgesimeter. According to the rat tail-flick test, 1.5% drug gels containing polyoxyethylene 2-oleyl ether and tetrahydrozoline showed the best prolonged local analgesic effects. In conclusion, the enhanced local anesthetic gels containing penetration enhancer and vasoconstrictor could be developed using the bioadhesive polymer.

• Applied Biological Chemistry
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• 제39권1호
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• pp.44-48
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• 1996

수분함량이 50%(건물당)인 쌀가루 겔을 $20^{\circ}C,\;4^{\circ}C,\;-18^{\circ}C$에서 1, 3, 6일 동안 저장하면서 ${\alpha}-$아밀라아제-요드법, 시차주사열량기, x-선 회절도를 이용하여 저장온도가 쌀가루 겔의 노화에 미치는 영향을 조사하였다. 쌀가루 겔의 노화는 저장기간이 경과함에 따라 증가하였으며, 특히 저장초기에 증가폭이 켰다. 저장온도에 따른 겔의 노화도는 $4^{\circ}C$에서 가장 높았으며 $20^{\circ}C,\;-18^{\circ}C$ 순이었다. 시차주사열량기로 측정한 쌀가루 겔 분말의 엔탈피는 ${\alpha}-$아밀라아제-요드법과 비슷한 경향을 보였으나, 저장온도간의 차이는 ${\alpha}-$아밀라아제-요드법이 더 뚜렷하였다. $4^{\circ}C$와 $20^{\circ}C$에서 저장한 겔의 x-선 회절도는 $2{\theta}=17^{\circ}$와 $20^{\circ}$에서 피크가 관찰되었으나 저장온도에 따른 차이를 구별할 수 없었다.

• 대한화장품학회:학술대회논문집
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• 대한화장품학회 2003년도 IFSCC Conference Proceeding Book I
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• pp.469-479
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• 2003

A novel branched wax has been developed for the control of the hardness of oil-wax gels. Using this wax, glossier application and smoother texture but tough lipstick can be obtained. Oil-wax gels are oily solids composed of liquid and crystalline solid oils (waxes). They are widely used in various cosmetic products, especially lipsticks. The control of gel hardness is one of the most important techniques in improvement of the lipstick quality. Addition of small amounts of commercial branched paraffin wax (e.g. microcrystalline wax, b-PW) to n-paraffin wax (n-PW) has been commonly used to increase gel hardness. However, gel hardness is very sensitive to the quantity of b-PW and the gel obtained is not always hard enough for practical use. In this study we examined the relationship between the gel hardness and the properties of the wax crystal in the gel. We have found that, when b-PW is added to n-PW, the wax crystal size becomes smaller (hardening the gels) and its crystallinity is decreased (softening the gels) simultaneously. Considering this result, we have developed a novel branched wax, Bis(polyethylenyl)- tetramethyldisiloxane (named ESE). ESE molecules are composed of a central tetramethyldisiloxane unit (branch unit) with polyethylene units at both ends. The central unit may suppress crystal growth while the ends are expected to prevent a decrease in wax crystallinity during crystallization. When ESE is added to n-PW, the wax crystal obtained becomes smaller without decreasing in crystallinity; consequently, the gel hardness is dramatically increased. By using ESE, the total amount of wax in a lipstick can be decreased by 30％ without spoiling the stick toughness, thereby achieving glossy application and smooth texture.

• 한국의류학회지
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• 제40권3호
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• pp.495-505
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• 2016

This study explores and selects an appropriate material that considers light and soft physical properties as well as activity for impact absorption pads that can be used to develop practical impact protective clothes worn during daily life by the elderly to reduce the impact of falls. Physical properties, impact absorption performance, and compression characteristics were evaluated on 5 types of foam, 2 types of 3D spacer fabric, and 3 types of polymer gel to select a material appropriate for the pad to be inserted into impact protective clothes. The evaluation of the physical properties showed that 3D spacer fabrics had lower density compared to other materials and polymer gels had the highest density. The elongation percentage was higher in foams than 3D spacer fabrics and EPDM foam had the highest elongation percentage. The impact absorption performance of honeycomb polymer gel was better than foams and 3D spacer fabrics. As a result of looking into compression energy and compression characteristics of materials, 'CR foam A' was found to absorb the largest amount of compression energy, 24.1%, among foams and polymer gels. A high energy absorption rate of 50.0% (or above) was indicated by 3D spacer fabrics; however, foams and polymer gels showed a progressive deformation of energy compression / recovery curve with 3D spacer fabrics that showed drastic deformation. Based on characteristics of materials, 'CR foam C' and EPDM with relatively high absorption performance can be used as protective pad materials among foams. Among polymer gels, 2 open-type polymer gels that have relatively low impact protective performance but a relatively lighter weight on human body (compared to closed-type) are considered appropriate protective pad materials.

• 한국식품조리과학회지
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• 제13권5호
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• pp.627-634
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• 1997

동부앙금의 단백질 함량이 높을수록 물결합력과 호화 개시 온도는 높았으나 팽윤력과 용해도, 광투과도는 낮은 값을 보였다. 최고 점도와 breakdown은 낮았으나, consistency와 setback은 높은 값을 보였다. 동부겔을 24시간과 48시간 실온에서 저장하면서 실시한 관능검사 결과는 단백질 함량이 높을수록 색깔과 투명도가 더 높은 값을 보였고 저장기간이 길수록 견고성, 응집성, 탄성, 종합적인 맛에서 더 높은 값을 보였으며 기계적 물성 검사 결과는 24시간 저장한 동부겔에서는 견고성, 껌성, 씹힘성의 특성치에서 단백질 함량이 높을수록 유의적으로 높았다. 그리고 48시간 저장한 동부겔에서는 견고성, 응집성, 껌성, 씹힘성의 특성치에서 유의적인 차이를 보였는데 응집성만 단백질 함량이 높을수록 더 낮은 값을 보였다.