The present paper shows high-resolution quasi-elastic neutron scattering (QENS) findings on homologues disaccharides (i.e. trehalose, maltose, and sucrose)-water mixtures as a function of temperature. The QENS measurements were performed on both partially deuterated disaccharides in D2O and on hydrogenated disaccharides in H2O to separate the solute dynamics from that of the solvent. The results highlight a noticeable disaccharide kosmotrope character, with results more marked for trehalose. Such evidence accounts for its higher bioprotective effectiveness.