Abstract: A process and apparatus for producing a frozen product or a freeze-dried product therefrom of, in particular, a material susceptible to denaturing due to existing enzymes, oxygen and heat, such as living organisms, organic compounds, vegetables, foods, fruits, drugs, biological samples, fodders and industrial raw materials while preserving the original qualities and properties, by recourse to a technique including the steps of mixing and crushing the material to be processed together with dry ice to thereby attain freezing of the material while replacing of the surrounding atmosphere by the thereby liberated carbon dioxide gas.