• 제목/요약/키워드: Gels

검색결과 729건 처리시간 0.034초

쌀전분으로부터 분리한 아밀로오스와 아밀로펙틴 혼합겔의 형태학적 구조 (Microstructure of Recombinated Gels of Amylose and Amylopectin Isolated from Rice Starch)

  • 백만희;신말식
    • 한국식품과학회지
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    • 제31권5호
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    • pp.1171-1177
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    • 1999
  • 쌀전분으로부터 분리한 아밀로오스와 아밀로펙틴이겔을 형성할 수 있는 최저농도로 아밀로오스와 아밀로펙틴 혼합겔을 제조하여 주사전자현미경과 X-선 회절기를 이용하여 겔 구조를 관찰하였다. 겔을 형성할 수 있는 최저농도인 용해성 아밀로오스 1.08% 농도에 아밀로펙틴을 $1.5%{\sim}7%$ 첨가하면 겔 그물망구조가 잘 형성되었고, 아밀로펙틴을 2%와 3% 첨가한 겔은 저장에 따라 $2{\theta}\;=\;17.0^{\circ}$에서 피크가 커졌다. 15% 아밀로오스/아밀로펙틴 혼합겔을 저장했을 때 아밀로오스 함량이 높을수록 단단하고 안정된 그물망구조를 이루었으며 생전분에서의 겔형성 양상과는 달리 아밀로오스와 아밀로펙틴이 함께 겔메트릭스를 이루는데 참여하는 것으로 생각되었고, 아밀로오스 함량이 증가할수록 $2{\theta}\;=\;17.0^{\circ}$에서 피크의 크기와 결정강도는 커졌다.

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도토리와 밤전분 gel의 물리적 특성 비교 (A Comparison Study on Acorn and Chestnut Starch Gels)

  • 이혜성;이혜수
    • 한국식품조리과학회지
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    • 제7권1호
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    • pp.11-14
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    • 1991
  • 가열온도를 달리하여 제조한 도토리와 밤 전분 gel의 물리적 특성을 비교한 결과는 아래와 같다. 1. $60^{\circ}C$로 가열한 경우 도토리보다 밤의 전분 입자가 훨씬 많이 풀어져 있었고, 도토리는 9$0^{\circ}C$$90^{\circ}C$로 가열한 gel에서 규칙적인 3차원적 망상구조를 보였으며 밤 전분 gel은 $70^{\circ}C$부터 미세한 다공성의 network를 보여 주었다. 2. X-ray 회절도는 두 시료 전분 gel모두 8~$11^{\circ}C$와 16~$19^{\circ}C$부근에서 두개의 약한 peak만을 보여주었다. 3. 3. Hardness는 70% 압착, 24시간 성형 gel에서, cohesiveness는 60% 압착, 3시간 성형 gel에서 크게 나타났으며, 특히 cohesiveness에서 압착율 변화에 의한 효과가 크게 나타났다. 또한 도토리는 90, $98^{\circ}C$에서, 밤은 $80^{\circ}C$에서 최고의 hardness값을 보였으며 cohesiveness는 두 시료 모두 가열 온도가 높아질수록 증가하였다.

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멥쌀 전분과 검물질 혼합물 겔의 특성 (Characteristics of non-waxy rice starch/gum mixture gels)

  • 신말식;권지영;송지영
    • 한국식품조리과학회지
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    • 제21권6호통권90호
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    • pp.942-949
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    • 2005
  • 쌀전분겔의 매트릭스와 구조를 안정화하고 텍스쳐 특성을 개선하기 위하여 멥쌀전분에 다양한 검물질을 혼합하여 겔을 제조하여 형태적, 텍스쳐 특성, 냉동-해동 안정성을 비교하였다. 검물질을 첨가하면 종류에 따라 다르나 쌀전분겔을 조밀하고 균일하여 안정된 매트릭스 갖게 할 수 있었으며 겔란검과 알긴이 효과적이었다. 쌀전분/검질 혼합 겔의 텍스쳐 특성도 검질에 따라 달랐으며 겔란검은 단단하고 알긴은 부드러운 겔을 형성하였다. X-선 회절도에 의하면 쌀전분겔은 V형의 결정형을 나타내며 검을 첨가하였을 때 $2\theta$ = $20^{o}$의 피크가 낮아졌다. 냉동-해동 안정성도 검물질을 혼합하였을 때 증가하였으며 겔란검과 알긴을 첨가한 쌀전분겔이 바람직 하였다.

친수성 다당류 첨가가 녹두전분 겔의 품질 특성에 미치는 영향 (Quality Characteristics of Mungbean Starch Gels with Various Hydrocolloids)

  • 최은정;오명숙
    • 한국식생활문화학회지
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    • 제24권5호
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    • pp.540-551
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    • 2009
  • This study was conducted to investigate the quality characteristics of mungbean starch gels containing various hydrocolloids (carrageenan, locust bean gum and xanthan gum) during room temperature storage ($25^{\circ}C$ for 24, 48 and 72 hours). Carrageenan and xanthan gum reduced the pasting viscosity of mungbean starch, whereas the locust bean gum increased the viscosity. The melting characteristics, as assessed by DSC, showed that carrageenan and xanthan gum delayed gelatinization of mungbean starch and the locust bean gum had no effect on this property. The lightness (L) of the gels with the locust bean gum was similar to that without the additive during storage, whereas that with carrageenan and xanthan gum was higher than that without the additive. Hardness, chewiness and gumminess of the gels with the locust bean gum was higher than that without the additive during storage, whereas that with carrageenan and xanthan gum was lower than that without the additive. The rupture stress, rupture strain and rupture energy of the gels with carrageenan and xanthan gum was lower than that without the additive during storage, whereas that with the locust bean gum was similar to that without the additive. In the sensory evaluation, springiness and cohesiveness of the gels with carrageenan and xanthan gum were lower than those without the additive, whereas springiness, brittleness and hardness of the gels with the locust bean gum were higher than those without the additive. In addition, the overall acceptability of the gels with the locust bean gum improved. The above results showed that carrageenan and xanthan gum lowered the quality characteristics of the mungbean starch gel and the locust bean gum improved them. Thus, the addition of 0.5% locust bean gum is an appropriate method for improving the quality characteristics of mungbean starch gel.

Study on the Controlled Gel Formation and Photochromic Properties of a New Cholesterol-bridge-naphthopyran Dyad

  • Sun, Lin;Wang, Guang;Liu, Longbo;Wang, Ai Xia
    • Bulletin of the Korean Chemical Society
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    • 제35권5호
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    • pp.1343-1348
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    • 2014
  • A cholesterol-bridge-naphthopyran dyad (NP-MCB) was designed and synthesized. NP-MCB can readily self-assemble into gels under ultrasound-radiation in several organic solvents and the formed gels easily transfer to solution by heat. This reversible process can be repeated many times. Scanning Electron Microscopy results showed that the morphologies of all formed xerogels in different solvents have fibrillar microstructure. The gels formation was due to energy and pressure afforded by the ultrasonic process, resulting in formation of molecular hydrogen bonding and molecular aggregation. NP-MCB displayed the normal photochromism both in solution and gel states. The kinetic results confirm that the colored merocyanine in gels show a slower fading speed than that in solution due to the compact aggregation of NP-MCB molecules in gels. The xerogel film formed in polar gelling solvent had large surface wettability than that in nonpolar gelling solvent.

솔-젤법에 의한 $Li_2O-ZrO_2-P_2O_5-SiO_2$계 유리 고체전해질의 제조와 그의 이온전도성 (Preparation of $Li_2O-ZrO_2-P_2O_5-SiO_2$ based Glassy Solid Electrolytes by Sol-Gel Process and Their Ionic Conduction)

  • 박강석;김기원;강은태
    • 한국세라믹학회지
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    • 제31권6호
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    • pp.660-670
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    • 1994
  • Transparent, crack-free dried gel monoliths with a composition of LiZr1.5Si2P2O12.5 have been synthesized by the low temperature polymerization of the Sol-Gel technique using metal alkoxides as starting materials. After initial reaction (20~40 min), each metal alkoxide closely paralleled each other during the hydrolysis reactions. The safe drying conditions of gels with no creaks the control of the shrinkage rate. The gels converted into the glass by heat treatment at 75$0^{\circ}C$. FTIR data indicated that the gels were phase separated into silicarich and phosphate-rich regions with the lithium. XRD results showed the formation of crystalline LiH2PO4. The gels dried at 15$0^{\circ}C$ or fired at 75$0^{\circ}C$ contained the residual water. The high ionic conductivity at room temperature for these gels was attributed to the motion of protons.

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Shape-Stabilized Phase Change Materials : Frozen Gels From Polypropylene and n-Paraffin for Latent Heat Storage

  • Kim, Jong-Hwan;Ko, Jae-Wang;Son, Tae-Won
    • 한국염색가공학회:학술대회논문집
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    • 한국염색가공학회 2009년도 학술발표대회
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    • pp.120-121
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    • 2009
  • We prepared polymer-PCM gels such as prepared frozen gel from polypropylene and n-Paraffin for thermal storage and release materials, their basic properties and possible applications especially in latent heat storage. The preparation methods are used to melting method and absorption method respectively. The composition and properties of prepared frozen gels from polypropylene and n-Paraffin were observed by DSC, FT-IR spectra, ARES and Elemental analysis. We can prepare frozen gels in different temperature for latent heat storage materials as controlling composition of phase change material as well as using different incorporating phase change materials. These frozen gels can be used to latent heat storage materials for several applications.

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BIOADHESIVE GEL PREPARATIONS FOR RECTAL DRUG DELIVERY

  • Kim, Nak-Seo-
    • 한국응용약물학회:학술대회논문집
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    • 한국응용약물학회 1993년도 제1회 추계심포지움 and 제2회 생리분자과학연구센터워크숍
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    • pp.21-24
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    • 1993
  • Many attempts have been made to use hydrogel as del ivory systems for various drug and vioactive materials to prolong and control their pharmacological activities. Rectal administration of drugs by using hydrogel bases, such as poloxamer ABA block copolymer (Pluronic F-127) gels, polyacrylic acid (Carbomer 934, 940, or 941) aqueous gels, and polyvilyl alcohol gels, have been reported on the preparation and potential suppository use of new gels(Eudragit L, Eudragit S, and Eudispert) that are block copolymers of methacrylic acid and methyl methacrylate. If) These hydrogel and xerogel preparations, especially Eudispert hv gels, show excellent staying and bioadhesive effects in the lower part of the rectum in rats and rabbits compared with those of polyethylene glycol (PEG)2000 and Witepsol H-15(or S-55) suppositories. Visual and optical microscopic observation of rectal membrances indicated no irritation or abnormality after administration of Eudispert hv tydrogel and xerogel.

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Shape-Stabilized Phase Change Materials : Frozen Gels From Polypropylene and n-Paraffin for Latent Heat Storage

  • Ko, Jae-Wang;Son, Tae-Won
    • 한국염색가공학회:학술대회논문집
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    • 한국염색가공학회 2010년도 제3회 국제학회
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    • pp.80-81
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    • 2010
  • We prepared polymer-PCM gels such as prepared frozen gel from polypropylene and n-Paraffin for thermal storage and release materials, their basic properties and possible applications especially in latent heat storage. The preparation methods are used to melting method and absorption method respectively. The composition and properties of prepared frozen gels from polypropylene and n-Paraffin were observed by DSC, FT-IR spectra, ARES and Elemental analysis. We can prepare frozen gels in different temperature for latent heat storage materials as controlling composition of phase change material as well as using different incorporating phase change materials. These frozen gels can be used to latent heat storage materials for several applications.

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Textural Properties and Structures of Wheat and Maize Starch-Gum Mixed Gels During Storage

  • Song, Ji-Young;Kim, Young-Chang;Shin, Mal-Shick
    • Food Science and Biotechnology
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    • 제17권1호
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    • pp.20-25
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    • 2008
  • Effects of commercial and lab-generated gellan gums on the textural properties, structure, and aging of wheat and maize starch gels were investigated using a rapid visco-analyzer (RVA), rheometer, scanning electron microscope (SEM), and X-ray diffractometer. Gellan and guar gums increased the peak and final viscosities, but xanthan gum and gum arabic reduced them. The maize starch had higher breakdown viscosity than the wheat starch, regardless of the type of gum. The hardness of all starch gels increased during storage, but their cohesiveness and springiness decreased. The degree of the gel hardness showed higher in maize starch than in wheat starch and the effect of gum addition had a difference with gum type. The wheat starch-guar and -gellan gum mixed gels showed higher elasticity and cohesiveness after storage. The starch-gellan gum mixed gels had dense and stable network structures, and were well maintained even after 7 days of storage. Most of the gums had anti-aging effect on X-ray diffraction pattern of starch gels.