The existance of a gel-glasslike transition in biopolymer gels such as egg-white, DNA, RNA/DNA mixtures, gelatin, agarose and konjak is demonstrated with the consideration of free water and bound water of gels. The time variations of the weight during the desiccation process of egg-white gel and several other gels were measured to be revealed as two or more stages. The first and second stages are attributed to the loss of the free and bound water in the egg-white gel, respectively. The gel-glasslike transition may be a common phenomenon for materials in which the molecular network contains free and bound waters. Heat treatment of egg-white gel and its crystallisation by irradiation at the glasslike state are also demonstrated, for the first time in denatured proteins such as egg-white, in association with the sol-gel-glass-crystalline transitions.
