The patented mixer combines a low-speed planetary stirrer with a conventional high-speed disperser. Both agitators revolve on their own axis while at the same time on a common axis. The high-speed blade provides an internal shearing action, while the planetary stirrer continually moves material into the high-speed blade. The action of the planetary blade also removes material from the tank wall to insure good heat transfer during the mixing process. Constructed in stainless steel to enable easy cleaning between batches. Also included are a jacketed mix vessel-mounted on non-sparking caster wheels, a specially-designed and machined vacuum hood enclosure and openings for charging of raw materials. Internal pressure operation is also available up to 15 psi. The unit is available in many sizes from 1/2 gallon to 750 gallons working capacity. The sanitary mixer is ideal for the development of viscous pharmaceutical, cosmetic and food products requiring a combination of slow and high-speed agitation. Vacuum design, a selection of materials of construction, complete control systems, wall scrapers, sanitary designs, etc., are available to suit the needs of each client.