CELL 17 |
| Aqueous slurries of normal corn and wheat starches were heated to 95oC for different times using a Rapid Viscoamylograph. The starch melts were poured into molds and cooled to form solid gels. Water in starch gels was replaced with ethanol in a series of solvent exchanges. Ethanol saturated gels were cryo-fractured and the internal structure was observed under SEM. Material, presumably amylose, started leaching out of the starch granules at temperatures as low as 70oC. This material forms a network of interconnecting strands that forms the matrix of the gel. The starch granules in both starches formed a porous core that was surrounded by a less porous shell as temperature and cooking times increased. The granule shell appeared thinner and the core was more porous for the corn compared to the wheat starch. Remnants of the starch granules from both wheat and corn starches persisted, even after 60 min cooking. |
|
Poster Session
4:00 PM-6:00 PM, Sunday, 10 September 2006 Moscone Center -- Hall D, Poster
Division of Cellulose & Renewable Materials |