Abstract: Apparatus for quick freezing aqueous solutions or suspensions to be submitted to lyophilization by means of which also the lyophilization time is strongly reduced, characterized in that it comprises:A. a tiltably hinged tank with refrigerated bottom and walls, the top being shut by a removable air-tight cover;B. one or more plates or rotating frames for carrying materials to be frozen, rotated at an adjustable speed by means of one or more driven shafts passing through the bottom of the tank.The rotating plate/s may be refrigerated independently from the external tank or, alternatively, may be only a frame, while a suitable stream of refrigerated air is created by means of an impeller fixed internally to the cover.