Abstract: A substantially pure rawhide product and a mechanical method for manufacturing a substantially pure rawhide treat or chew for pets utilizing a double screw extruder with a number of heating zones and interchangeable extrusion dies. The method allows for the use of wet rawhide or rawhide scraps and contemplates the addition of various additives to the rawhide product. Also claimed is a double screw extruder especially adapted for the preparation of substantially pure rawhide treats.

Abstract: The process for continuously preparing a food product constituted by a thin paste based on a plant product contributing starch includes the steps of introducing at the upstream end of a screw conveyor the plant product with a liquid phase, kneading and grinding, cooking the mix at a temperature between 80.degree. C. and 110.degree. C. with kneading, introducing eggs, fatty substances and products of animal or plant origin essentially containing proteins, homogenization and fine grinding of the mix, and extruding the mix through a die placed at the downstream end of the screw conveyor.