Chocolate tempering machines (or temperers) with computer controls can be used for producing consistently tempered chocolate. In particular, continuous tempering machines are used in large volume applications. Various methods and apparatuses for continuous flow tempering have been described by Aasted, Sollich and Buhler, three manufacturers of commercial chocolate equipment, with a focus now on energy efficiency. In general, molten chocolate coming in at 40–50 °C is cooled in heat exchangers to crystallization temperates of about 26–30 °C, passed through a tempering column consisting of spinning plates to induce shear, then warmed slightly to re-melt undesirable crystal formations.