High Specific Mechanical Energy extruder screw assemblies (14, 88, 98) and complete extruders (10, 86, 96) are provided, which include wide-flight intermediate screw sections (104) having axial flight widths greater than the flight widths of the inlet and outlet screw sections (102, 106) on opposite sides of the intermediate sections (104). The intermediate sections (104) provide increased friction and shear serving to enhance the SMEs imparted to comestible food materials during processing thereof.

An extruder for making meat analogue products, where the extruder comprises a product outlet (22), and a longitudinal barrel (8) comprising an inner surface (14) and an outer surface, and where the extruder further comprises heating means for heating at least a part of said inner surface, where said barrel (8) interconnects with said product inlet (5) and outlet (22), where the extruder further comprises a rotor (16) arranged coaxially inside said barrel (8), where said rotor (16) comprises drive means (19) for rotating said rotor (16) in relation to the barrel (8).

Puck and collar alignment device embodiments facilitate simultaneous insertion of free end portions of screw shafts into open end portions of complementary drive couplings. The embodiments have alignment keys that correct deviations in alignment and rotation introduced while moving the screw shafts though a barrel of an extruder. Tapered front faces of the alignment keys incrementally adjust coaxial alignment, and tapered side faces of the alignment keys incrementally adjust rotational position cooperatively between the alignment devices and drive couplings. The coaxial and rotational position adjustments cooperate to simultaneously guide multiple alignment keys to fit within corresponding keyway sections while providing alignment of external splines on the screw shafts to interlock in a timed relationship with internal splines on the drive couplings during the simultaneous insertion.

An extruder screw including an elongated cylindrical tension rod; screw segments including radially protruding functional elements configured to feed, mix, and/or knead an extrudate, and a respective pass through bore hole oriented in a longitudinal direction of the extruder screw, wherein the screw segments are slid onto the tension rod with the pass through bore hole and axially supported at a tip of the tension rod; a counter element that clamps the screw segments against the tip of the tension rod at an end of the tension rod wherein the end is arranged distal from the tip; and a locking element that is clamped between the screw segments and the counter element.

An extruder screw having a worm shaft and a plurality of screw elements that are releasably plugged or pluggable thereon, wherein each screw element has a defined axial minimum length or a length that corresponds to a multiple of the minimum length. The worm shaft has an external toothing and the screw elements have an internal toothing engaging therewith. The external toothing has, forming individual gear rings extending around the circumference, a plurality of recesses extending around the circumference in an offset manner along its axial length, which are spaced apart from one another by the minimum length, such that the internal toothing of each screw element extends, at both axial ends, into the region of the recess, and the ends of the internal toothing are not engaged with the external toothing.