A pet food product is produced having a coloured exterior that simulates the appearance of real meat that has been a marinated or grilled appearance. The product may be manufactured using a vegetarian (meat free) formulation or a formulation combining meat with dry proteinaceous materials. The ingredients are processed to form an emulsion-like mixture, which is rapidly heated in a confined zone to allow the protein to coagulate. An injector/shredder assembly is positioned in the zone to disrupt and shred the coagulated product mass and inject a colourant. The colourant adheres to some of the exterior surfaces of the final product to create a simulated grilled or roasted appearance.