• 한국가스학회지
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• 제15권5호
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• pp.13-18
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• 2011

폭발챔버에서 Agar gel barrier의 폭발완화 특성을 조사하기 위하여 실험적 연구를 수행하였다. 단면적 $100{\times}100mm^2$, 길이 1400 mm를 가지는 폭발챔버 그리고 폭발챔버의 개구부에 설치될 gel barrier의 고정을 위하여 $100{\times}100{\times}300mm^3$의 챔버를 제작하였다. Agar gel과 물을 혼합하여 4가지 서로 다른 농도(2, 3, 4, 5 %)를 가지는 agar gel barrier를 제조하여 실험변수로 사용하였다. 폭발과정 동안 gel displacement의 가시화를 위해 고속카메라 그리고 gel barrier 전 후단의 폭발압력 변화를 관찰하고자 압력획득시스템을 사용하였다. 실험결과, gel 농도 증가에따라 gel의 파열시간 및 최대 폭발압력 도달시간이 지연되는 것으로 나타났다. 또한, gel 농도가 증가할 때 gelbarrier 전 후단에서의 폭발압력 완화율이 증가하는 경향으로 나타났다.

• 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.

• 한국식생활문화학회지
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• 제23권4호
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• pp.499-506
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• 2008

This study was conducted to determine the quality characteristics of grape jellies for the elderly. The jellies contained sugar (control) or sugar derivative sweeteners (erythritol, isomaltooligosaccharide, sorbitol, and xylitol). Agar (0.31%) and $\kappa$-carrageenan (0.27%) were the gelling agents. The average age of the subjects participating in the acceptance test was 79. The lightness (L), redness (a), and yellowness (b) values of the agar gel with erythritol mostly decreased, indicating a darker and pale red color. The L and b values of the carrageenan gel with sugar derivative sweeteners increased, indicating brighter and yellowish color. The agar and carrageenan gels with sorbitol showed higher gelling and melting temperature, indicating that gelation occurred easily and did not easily melt. The agar and carrageenan gels with xylitol showed a low-melting temperature, indicating low stability with temperature change. The break-down rate of the agar and carrageenan gels with erythritol was low, whereas that of agar gel with sorbitol was relatively high despite its high melting temperature. Hardness, cohesiveness, gumminess, and chewiness of the gels with sugar derivative sweeteners decreased, and this tendency was most distinct with isomaltooligosaccharide in the agar gel and with sorbitol in the carrageenan gel. The rupture properties of the gel were the same as the hardness of the gel. Sensory acceptance of the agar gels with erythritol, sorbitol, isomaltooligosaccharide, and the carrageenan gel with erythritol was fairly high, whereas that of the agar gel with xylitol and the carrageenan gel with isomaltooligosaccharide and xylitol was low. The results show that sorbitol and erythritol are appropriate as sugar substitutes in grape jellies for the elderly about the acceptability and stability of the gels.

• 대한수의학회지
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• 제10권2호
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• pp.1-5
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• 1970

In these studies the efficracy of plate, tube agglutination and agar-gel precipitin test were compared for the detection of pullorum infected chickens. From all the chickens showing positive reaction in agar-gel precipitin test, Salmonella pullorum organisms were isolated.

• 한국식품과학회지
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• 제31권1호
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• pp.110-114
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• 1999

제주도산 우뭇가사리로부터 agar를 제조하여 분석용 등급의 agarose 제조를 위하여 cetylpyridium chloride (CPC), polyethylene glycol (PEG), chitosan을 처리하여 agaropectin을 제거하여 agarose를 분리, 정제하였다. 3가지 방법중 chitosan을 처리하여 정제한 agarose는 황산기 함량이 가장 낮았으며, electroendosomosis도 가장 낮은 수치를 나타내어 분석용 agarose 제조를 위한 가장 효율적인 방법으로 나타났으며 실제 DNA 전기영동 실험에서도 가장 우수한 resolution을 나타내었으며 교차면역 전기영동에서도 시판되고 있는 제품에 비하여 품질이 양호함을 알 수 있었다.

• Journal of Microbiology
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• 제34권4호
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• pp.384-386
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• 1996

Application of polyacrylamide gel (PAG) instead of agar to solid cultures of Streptomyces spp. was studied. The improved media were prepared by 1) gelling 20 ml of 5% acrylamide in a glass petri dish at room temperature, 2) washing by running water for more than 8 hr to remove residual reaction reagents, 3) drying at 5$0^{\circ}C$ for 12 hr to make a gel film, 4) autoclaving at 121$^{\circ}C$ for 15 min, and 5) swelling gel for about 4 hr by adding sterile liquid medium. In PAG media there were no differences from the observation of morphological characteristics showing during the cellular differentiation on agar media, whereas the ability to utilize carbohydrates differed somewhat from agar media. Agar media thus were little favorable for biochemical tests which the growth was determined depending on the formation of colony, but washed PAG was superior to serve as a solidifying agent.

• Food Science and Biotechnology
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• 제16권2호
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• pp.183-186
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• 2007

The type of mixed gel network of $\kappa$-carrageenan/agar was determined by applying rheological principles. Apparent Young's modulus of the mixed gels was mathematically analyzed with (a) simply adding the moduli of two component gels, (b) phase-separated type's upper and lower bound models, (c) interpenetrating type's logarithmic model. The experimental data fitted the estimates from the operation (a). Whereas, as for the models (b), the experimental values in the agar-rich region fitted the estimates of the upper bound model, but in the $\kappa$-carrageenan-rich region slightly deviated from those of the lower bound model. It reflected an evidence of a phase-separated type, although it was not typical, that there must be data good-fit in the agar-rich and $\kappa$-carrageenan-rich regions with the upper and lower bound models, respectively. Experimental values disagreed with estimates of the model (c). Gel time was analyzed to evince the phase-separated type. As agar concentrations increased at a fixed amount of $\kappa$-carrageenan, gel time gradually decreased and then sharply increased and decreased again. The pattern of such change in gel time also represented a typical behavior of phase-separated type's mixed gels.

• 생명과학회지
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• 제13권3호
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• pp.258-264
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• 2003

콩의 영양성과 우무의 기능성을 더하여 간편하고 편의성을 크게 증가시킨 고영양의 콩 음료 제품의 개발적성을 검토하였다. 적당한 조직감을 갖는 우무의 제조 조건으로는 1.5% 한천에 Nacl 0.1∼0.2%, glucomannan 0.1%를 첨가하는 것이 최적 조건으로 판단되었다. 그리고 콩물의 제조는 방치시 침전물의 양과 점도의 변화 등을 볼 때 고형물 10%에 설탕 3% 및 식염 0.1∼0.2% 첨가가 좋은 것으로 나타났다. 관능검사 결과 콩음료의 최적 제조조건으로는 한천 1.5%에 Nacl 0.2% 및 glucomannan 0.1%를 첨가하여 만든 우무를 고형물이 10%인 콩물에 설탕 3% 및 식염 0.1∼0.2%를 첨가하여 만든 콩물에 혼합하여 제조하는 것으로 하였다.

• 한국의학물리학회지:의학물리
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• 제27권4호
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• pp.224-231
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• 2016

The usefulness of Gel Bolus phantom was investigated by comparing the temperature distribution characteristic of the agar phantom produced to investigate the dose distribution characteristic of radiofrequency hyperthermia device with that of the Gel Bolus phantom under conditions similar to those of an agar phantom that can continuously carry out temperature measurement. The temperatures of the agar phantom and the Gel Bolus phantom were raised to $36.5{\pm}3^{\circ}C$ and a temperature sensing was inserted at depths of 5, 10, and 15 cm from the phantom central axis. The temperature increase rate and the coefficient of determination were analyzed while applying output powers of 100 W and 150 W, respectively, at intervals of 1 min for 60 min under conditions where the indoor temperature was in the range $24.5{\sim}27.5^{\circ}C$, humidity was 35~40%, internal cooling temperature of the electrode was $20^{\circ}C$, size of the upper electrode was 250 mm, and the size of the lower electrode was 250 mm. The coefficients of determination of 150 W output power at the depth point of 5 cm from the central axis of the phantom were analyzed to be 0.9946 and 0.9926 in the agar and Gel Bolus phantoms, respectively; moreover, the temperature change equation of the agar and Gel Bolus phantoms with time can be expressed as follows in the state the phantom temperature is raised to $36^{\circ}C:Y(G)$ is equation of Gel Bolus phantoms (in 5 cm depth) applying output power of 150 W. Y(G)=0.157X+36. It can be seen that if the temperature is measured in this case, the Gel Bolus phantom value can be converted to the measured value of the agar phantom. As a result of comparing the temperature distribution characteristics of the agar phantom of a human-body-equivalent material with those of the Gel Bolus phantom that can be continuously used, the usefulness of Gel Bolus phantom was exhibited.

• 한국식품조리과학회지
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• 제7권2호
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• pp.19-23
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• 1991

본 연구에서는 gel화를 유도할 수 있는 첨가제를 첨가하여 만든 5가지 옥수수 전분 gels와 아무것도 첨가하지 않은 control옥수수 전분 gel의 관능적 물성적 특성을 조사 비교하였다. 1. 관능검사를 실시한 결과 \circled1 Agar의 hardness는 control보다 유의하게 높았고, pectin은 control 보다 유리하게 낮았다. \circled2 CMC와 pectin의 adhesiveness는 control 보다 유의하게 높았고 agar는 control보다 유의하게 낮았다. \circled3 전체적인 acceptability는 CMC와 Pectin은 control보다 유의하게 선호도가 낮았고 나머지 시료들은 control과 유의차가 없었다. 2. Instron을 이용한 물성검사 결과 \circled1 Agar의 hardness는 control보다 유의하게 높았고, 나머지 시료들의 hardness는 control보다 유의적으로 낮았다. \circled2 Agar와 casein의 cohesiveness는 control보다 유의하게 높았으며 gelatin은 control보다 유의하게 낮았다. 3. 관능검사나 Instron에 의한 기계적 검사에 있어서 시료의 차이를 가장 잘 구분해 주는 특성치는 hardness라고 생각되어진다