A systematic study of the experimental behavior of apparent molal volumes and viscosities of DL-alpha-alanine in aqueous 1-propanol, 1-butanol and 1,2-propanediol mixtures at 25 degrees C is presented. The concentrations of the alcohol-water mixtures used as solvents were selected taking into account their special thermodynamic behavior and in particular the abrupt change observed in the dependence of partial molal volumes with concentration. The results are discussed in terms of changes in solvent structure.