The apparatus (100) includes a die head (118) for extruding a main comestible material to form an extrudate body. A plurality of nozzles (160, FIG. 7) is located within the die head for introducing a comestible fluid into the extrudate body to form a plurality of filled capillaries. A control system (182) is capable of selectively connecting at least one of the nozzles to any one of at least two different fluid filling sources (150A, 150B). The control system may be capable of connecting each of the nozzles independently to different fluid sources or the nozzles may be arranged into two or more groups of fluidly interconnected nozzles that can each be independently switched between different fluid sources. The apparatus can be used to form products in which the fillings in the capillaries are varied or in which an image is formed in cross section. The apparatus can also be used to switch production between products having different fillings without stopping extrusion.