Natural polysaccharides are supports for sensors, absorbents and catalysts. They are also gelling agents in the aqueous phase, due to the high level of dispersion of hydrocolloids. This article focuses on an effective method to prepare dry materials which retain the dispersion of the polymer hydrogel, namely polysaccharide aerogels. The diverse surface functionalities like hydroxy, carboxy or amino groups of the polysaccharide aerogels are accessible to catalysts and reactants and can be easily modified to tune the functionality of the materials.