Abstract: Polysaccharides are often used as thickening, stabilizing and gelling agents in the food and nonfood industries. The structure-function relationship of the polysaccharides from the view point of the rheological characteristics in aqueous solutions has been developed and accomplished.
Gelation mechanism: Gelation mechanism for kappa-carrageenan, iota-carrageenan, agarose (agar), deacetylated gellan gum, alginic acid, curdlan, amylose, deacetylated rhamsan gum and native gellan has been analyzed at the molecular level where sulfate oxygen, ring oxygen, hemiacetal oxygen, cations, hydroxyl groups, and methyl groups take part in the intra- and intermolecular associations with ionic bonding, electrostatic forces of attraction, hydrogen bonding and van der Waals forces of attraction.
Co-gelation mechanism: Synergistic co-gelation mechanism of Xanthan gum produced by plant pathogen bacterium (Xanthomonas campestris) with galactomannan (locust-bean gum, tara-bean gum, guar gum, Leucaena galactomannan and Delonix regia galactomannan), and with konjac glucomannan, where trisaccharide side-chains of the former molecules including pyruvate groups contributed with hydrogen bonding and van der Waals forces of attraction has been analyzed.
Thermal stability: The molecular origin for the thermal stability for viscosity and dynamic viscoelasticity of non-gelling welan, rhamsan, S-657, S-88, S-198 gum, schizophyllan and amylopectin (rice, potato and wheat) the structure of which is similar to that of gelling gellan, curdlan and amylose has been analyzed. Especially, the gellan gum families of the polysaccharides (welan, rhamsan, S-657, S-88 and S-198 gum) have given a good opportunity to investigate the structure-function relationship of the polysaccharides.
Gelatinization and retrogradation mechanism of starch: Gelatinization and retrogradation mechanisms of rice, potato and wheat starches have been analyzed.
Principle of polysaccharide gels: From the results and discussions, the principle of the polysaccharide gels has been established. Though many investigations concerning the gelling properties of the polysaccharides have been done to discuss structure-function relationship, no one has established gelation mechanism at the molecular level except the author.

Brief Biography of the Speaker:
Masakuni Tako Ph D is a professor of Department of Subtropical Bioscience and Biotechnology, University of the Ryukyus, Okinawa, Japan. His area of expertise is polysaccharide bio-physical chemistry. Besides being an author and co-author of 105 papers, he wrote 3 chapters in different books of polysaccharides. He has also published 3 books of Ludwig van Beethoven who is famous music composer. Awards Research promotion award in Okinawa "Study on the application of membranes in sugar manufacturing industry"(1996). Award of the Japanese Society of Applied Glycoscience "Studies on the gelation mechanism of polysaccharides, and development and application of fucoidan from commercially cultured Cladosiphon okimuranus"(2008).