The effect of storage on wheat-rye bread was investigated using water activity and dynamic mechanical analysis. The time course of changes in the water activity in bread crumb in the process of staling reflects the occurrence of spatial cross-linking of the macromolecular com-ponents of bread crumb from the amorphous regions and the effect of restructuralisation of starch spherulites disintegrated in the process of baking. The above mechanisms have consid-erably different kinetics. The time constant of the initiation of connections in the amorphous phase is over 6 h, whereas the time constant of the recrystallisation process reaches about 90 h. The postulated changes in the bread crumb structure are reflected in the time evolution of the dynamic mechanical properties of bread.