The invention relates to a method for preparing a food product by means of co-extrusion, wherein a casing composition (3a) and a barrier composition (4a) are co-extruded as layers upon an edible filler (5a), such that the edible filler is provided with a casing layer (3) and a barrier layer (4). After co-extrusion, said barrier layer is present between the edible filler and the casing layer. Advantageously, the casing composition comprises collagen, a polysaccharide and water. In embodiments, the casing composition may comprise collagen in an amount of between 2 and 7 wt. %, preferably between 3 and 6 wt. %； and, the casing composition may comprise a polysaccharide in an amount of between 1 and 5 wt. %, preferably between 2 and 4 wt. %. Further, the invention relates to a food product. The food product, for instance a sausage, comprises an edible filler, a casing layer, and a barrier layer, wherein the edible filler is covered by the barrier layer at least partly, and wherein the barrier composition is coverer by the casing layer at least partly.
