The present invention relates to a method and production line for inline processing of food products. The method comprises the step of co-extruding a food dough into a flow of co-extruded food products having a casing that comprises a protein, or a hybrid casing of a protein and a polymer, wherein the method subsequently comprises the successive steps of: a) subjecting the flow of co-extruded food products to a food product strengthening step, b) subjecting the flow of food products to a thermal treating step, and c) optionally, subjecting the thermally treated flow of food products to a post-thermal treating step, wherein in step b) the flow of food products is at least subsequently subjected to a first thermal treating step, and a second thermal treating step.
