Disclosed is a dry glassy composition, comprising a bioactive material, at least one matrix forming agent and at least two glass forming agents, wherein the bioactive material comprises viable bacteria in a concentration greater than 10 billion CFU/g dry composition. Further disclosed is a method for preparing a dry glassy composition comprising a bioactive material, a matrix forming agent and two glass forming agents, said method comprising: (a) combining the bioactive material, the matrix forming agent and the two glass forming agents in an aqueous solvent to form a viscous slurry； (b) snap-freezing the slurry to form particles； (c) primary drying of the particles from step (b) under vacuum and at a temperature above the freezing point of the particles； (d) secondary drying of the primarily dried particles from step (c) under full vacuum, whereby the dry glassy composition is prepared.
