2000 Volume 47 Issue 1 Pages 49-53
The author and colleagues have proposed a gelation mechanism for K -carrageenan, c -car-rageenan, agarose (agar), gellan gum, curdlan, amylose, and alginic acid at the molecular level in aqueous solutions in preceding papers. The synergistic gelation mechanism between xanthan gum and galactomannans (locust-bean, tara-bean and guar gum), and konjac glucomannan, where trisac-charide side-chains of the former molecule take part in the interaction, have been proposed. The synergistic gelation mechanism between K -carrageenan and galactomannan (locust-bean gum) has also been proposed. Recently, we have proposed gelatinization and retrogradation mechanisms of rice starch. The polysaccharides in water changed into an ice-like structure with hydrogen bonding between polymer and water molecules, and between water molecules even at a concentration range of 0.1-1.0% (w/v) at room temperature, resulting in gelation. Such dramatic changes from liquid into gels have not yet generally been understood at the molecular level. The research conducted by the author now makes it possible to discuss, in principle, because structure-function relationships from the viewpoint of rheology not only of the gelling polysaccharides mentioned above, but also of non-gelling welan, rhamsan, S-657 gum, schizophyllan, and amylopectins (rice and potato), the structure of which is similar to that of gelling gellan gum, curdlan and amylose, have also been analyzed at the molecular level in our preceding papers.