The investigations on water absorption by extrudates showed beneficial effect of the glycerol content on the reduction of WAI index. The influence of a glycerol addition on water absorption was similar for all starchy components contrary to measurement of the moisture content of the extrudates stored in different relative humidity conditions. At the relative ambient moisture higher than 60%, the corn TPS samples with highest glycerol concentration showed the highest water content. When ambient moisture exceeded 75%, water content in these samples proved higher than in the extrudates without glycerol. This could happen because at high ambient moisture, amylose absorbs greater amount of water compared to amylopectin and the crystallisation reduces water absorption of hydrophilic polymers