Extruder system and method

A method of increasing starch gelatinization in a starch-containing pet food product, comprising the steps of:

• providing a multi-extrusion apparatus including:
• a primary extruder and a plurality of satellite extruders, each extruder having an axially rotatable screw within a barrel and configured to move material from a barrel inlet, through the barrel, and out through a barrel outlet, and
• a manifold connected to the primary extruder and the plurality of satellite extruders having an inlet and a plurality of separate outlets and operable to separate said material passing through the barrel outlet of said primary extruder into a plurality of separate material streams, each stream passing through one of said manifold outlets and into an inlet of one of the satellite extruders;
• processing a starch-containing pet food mixture by extrusion through the primary extruder at a first temperature and first shear conditions, wherein the starch-containing pet food mixture does not include a hydration competitive components or a temperature or shear sensitive ingredient;
• next passing the extruded starch-containing mixture through the manifold to form a plurality of separate material streams and directing each of the streams to an inlet of one of the satellite extruders;
• adding a hydration competitive component and a temperature or shear sensitive ingredient to at least one of the satellite extruders and not to the primary extruder;
• and
• processing the material streams, the hydration competitive component, and the temperature or shear sensitive ingredient by extrusion through the at least one of the satellite extruders at a second temperature that is lower than the first temperature and the second shear conditions that are lower than the first shear conditions;
• wherein the bioavailability of the shear or temperature sensitive ingredient is increased in the final extrusion product in comparison to final extrusion products processed in a single extruder.