Kneading machine for food products and a method of kneading which can be performed by the machine

A kneading machine for forming a continuous elongated mass of a mixture of food products, particularly of dough, comprising:

• a container for the product to be kneaded, constituted by a horizontal channel-shaped element along which the mixture being formed is advanced and which has an input end for admitting the product to be kneaded and an output end for discharging the mixture produced;
• a plurality of helical kneading tools arranged in the channel-shaped element so that the product advancing along the channel-shaped element encounters them in succession, each helical kneading tool having a cylindrical envelope with a vertical axis which intersects orthogonally a central axis of a duct defined by the channel-shaped element, the cylindrical envelopes of the respective kneading tools being in contact with each other and with the walls of the channel-shaped element;
• drive means for rotating each helical kneading tool around its vertical axis;
• and
• auxiliary drive means for imparting a cyclic movement to said channel-shaped element relative to the kneading tools, while keeping said channel-shaped element horizontal, said cyclic movement including a first stage of horizontal movement against the flow of the product, a second descending stage, a third stage of horizontal movement with the flow of the product, and a fourth stage in which it ascends again.