The process comprises preparing a main continuous filled line (VI, V2, V3) by extrusion comprising an external layer (Cl, C2, C3) of main material surrounding an inner layer (Gl, G2, G3) of a liquid, semi-liquid or pasty filling material, treating the main material, before, during and/or after the preparation of the main continuous line to increase the cohesion of the animal meat pieces constituting the main material, and dividing the main continuous line into small portions by squeezing the outer layer of treated main material transversely to drive out the filling material. The process comprises preparing a main continuous filled line (VI, V2, V3) by extrusion comprising an external layer (Cl, C2, C3) of main material surrounding an inner layer (Gl, G2, G3) of a liquid, semi-liquid or pasty filling material, treating the main material, before, during and/or after the preparation of the main continuous line to increase the cohesion of the animal meat pieces constituting the main material, and dividing the main continuous line into small portions by squeezing the outer layer of treated main material transversely to drive out the filling material of the inner layer, then by cutting the main line at the squeezed area devoid of lining material for forming portions (PI, P2, P3). The treatment step comprises cooling the main material at a temperature of less than 0[deg] C and greater than the freezing point of the main material, and agglomerating a part of animal meat by a gelling agent. The cooling is carried out by extruding the main material into continuous outer layer. The inner layer of filling material constitutes less than one third of the thickness of the main continuous line in cross section. The outer layer is prepared by extrusion of chopped animal meat into fibrous pieces of a length of = 10 mm and a cross section of = 20 mm 2>;. The main continuous line (V3) is obtained by extruding a lower continuous secondary layer (Cl) of main material, extruding an inne