Abstract: A system for combining, mixing, and further processing ingredients to produce a specified weight of a composition in accordance with a specified recipe. The ingredients are discharged from hoppers into a central conveyor. Each hopper operates under control of a hopper controller that regulates the discharge rate and controls refilling of its associated hopper. The ingredients are mixed in the central conveyor as they are transferred to a processing device, such as a mill or roaster, and then discharged from the processing device into a network of conveyors for transfer to another location for further handling. The system operates under the control of a central controller which regulates the discharge rates of the various ingredients to optimize the feedrate to the processing device.