Amylose is a hydrocolloid. Its extended conformation causes the high viscosity of water-soluble starch which varies relatively little with temperature. The extended loosely helical chains possess a relatively hydrophobic inner surface that is not able to hold water. Amylose forms useful gels and films. Its association and crystallization (retrogradation) on cooling and storage decrease storage stability, causing shrinkage and the reléase of water (syneresis). Increasing amylose concentration decreases gel stickiness, but increases gel firmness. Amylopectin interferes with the interaction between amylose chains (and retrogradation) and its solution can lead to an initial loss in viscosity and followed by a more slimy consistency.