Herein described is an apparatus for shredding and mixing fibrous products intended for preparing animal food products, of the type comprising a tank or vat within which there is mounted a shredding and mixing device consisting of a rotor or auger comprising a rotary shaft on which there is mounted a plurality of mixing elements. Each mixing element consist of a scraper blade operatively connected to an upper end of a supporting rod, while the lower end of the supporting rod is fixed on the lateral surface of the rotary shaft through a respective fixing plate. Each scraper blade is rotatable around the axis of the supporting rod thereof and it is provided with elastic means which allow the scraper blade to rotate around the relative supporting rod according to a predefined angle in the case where the scraper blade finds an obstacle during the rotation of the shaft, as well as returning the scraper blade in the initial position thereof at the moment when the obstacle has been overcome or removed. The axis of at least part of the supporting rods of the scraper blades is inclined according to two predefined inclination angles with respect to two corresponding planes respectively parallel and perpendicular to the axis of the rotary shaft. The predefined inclination angles are determined as a function of the rotation direction of the scraper blades and of the position of the scraper blades along the rotary shaft. The predefined inclination angles allow each scraper blade, though rotating around the axis of the supporting rod thereof, to always describe circumferences which maintain the scraper blade equally spaced apart from the inner surface of the tank or vat.
