The free volume of trehalose matrices was investigated using position annihilation lifetime spectroscopy (PALS). A study was performed to analyze the organization and mobility of water in amorphous and crystalline states. PALS method measured the free volume holes that existed between molecules in soft condensed molecules by formation and subsequent annihilation of ortho-positronium. This interaction captured water from the amorphous phase by locally forming a drihydrate, and a concentration-independent mobility of water along molecular channels in dihydrate. It allowed the crystallites to act as a sink and a source of water in low-moisture systems at ambient temperatures. It was found from nanostructural analysis that the anomalous properties of trehalose in anhydrobiosis arise from a combination of a high stability of the glassy state, and a specific structural interaction with water in the crystalline state.