Methods of simultaneously forming feed particles of different densities involves extruding a heated feed through an extruder having an extruder die defining a plurality of die openings. A first plurality of the die openings comprises a land length that is at least two times as long compared to a diameter of a respective die opening. A second plurality of the die openings comprises a land length that is equal to or less than a diameter of a respective die opening. Extrusion through the first plurality of the die forms extruded ribbons with a first density, while extrusion through the second plurality of the die openings forms extruded ribbons with a second density that is lower than the first density. The method proceeds by cutting the first and second plurality of extruded ribbons to simultaneously form feed particles of the first and second densities.