Abstract: An improved, dual-shaft preconditioner (10, 70, 102) is provided having independent drive mechanism (18, 20, 78, 80) operatively coupled with a corresponding preconditioner shaft (14, 16, 74, 76, 106, 108) and permitting selective rotation of the shafts (14, 16, 74, 76, 106, 108) at rotational speeds and directions independent of each other. Preferably, the speed differential between the shafts (14, 16, 74, 76, 106, 108) is at least about 5:1. The mechanisms (18, 20, 78, 80) are operatively coupled with a digital control device (60) to allow rotational speed and direction control. Preferably, the preconditioner (10, 70, 102) is supported on load cells (62, 100) also coupled with control device (60) to permit on-the-go changes in material retention time within the preconditioner (10, 70, 102).

Abstract: Improved preconditioners (10) are provided for partial moisturization of human food or animal feed ingredients prior to downstream final processing thereof in an extruder (56) or pellet mill. The preconditioner (10) preferably includes an elongated housing (12) having a wall (14) with an inlet (20) and an opposed outlet (22). The housing (12) also has a larger diameter end wall (16) proximal to the inlet (20), a smaller diameter end wall (18) proximal to outlet (22), and a progressively converging housing wall (14) with a taper angle of from about 2-9°. A shaft (36) extends along the length of housing (14) and supports a plurality of outwardly extending mixing elements (46) positioned in axially and circumferentially spaced relationship along the length of the shaft (36). The outer margins (54) of the mixing elements (46) cooperatively define a taper along the length of the housing wall (14).

Abstract: High-capacity extrusion die assemblies (20, 90, 130, 140, 180, 252) each having a tubular sections (44, 146, 162, 268) and an elongated, axially rotatable, helically flighted screw section (56, 56a, 152, 168, 276, 278) which cooperatively define frustoconical, outwardly diverging material flow paths (75, 160, 291) at constant or differing divergence angles of from about 1-11°. The use of diverging tubular sections (44, 146, 162, 268) and screw sections (56, 56a, 152, 168, 276, 278) permits the use of larger die plates (76, 118, 292) with an increased number of die openings (80, 124, 296). This allows significant increases in extrusion production rates. The die assemblies (20, 90, 130, 140, 180, 252) can be used in the production of a wide number of human foods or animal feeds, and particularly aquatic feeds of the floating or sinking variety.

Abstract: The present invention is directed to improved preconditioners (12) especially useful for the production of high meat-content pet foods. The preconditioners (12) include an elongated housing (16) with one or more elongated, axially rotatable mixing shafts (18, 20) therein, each having a plurality of outwardly extending mixing elements (42, 44). The preconditioner (12) is provided with apparatus (56) for directing relatively large quantities of heated non-steam gas into the preconditioner (12) in lieu of most or all of the steam normally used with preconditioners. This serves to heat material passing through the preconditioner (12) without the addition of substantial moisture.

Abstract: Improved, low- or no-waste control methods for food processing systems including a preconditioner (14) and a downstream processing device such as an extruder (16) are provided. The control methods include both startup and shutdown sequences, and an optional flush sequence. During startup, a gate (64) of preconditioner (14) is initially closed and is thereafter sequentially opened to a full open, normal operating position after predetermined preconditioner temperature and/or weight set points are achieved. Shutdown involves terminating the flow of ingredients to the preconditioner (14) while the gate (64) remains open, with the preconditioner operated to deliver the preconditioned material within the preconditioner (14) to the extruder (16) for as long as possible in order to minimize any residual waste within the preconditioner.

Abstract: High-capacity extrusion die assemblies (20, 90, 130, 140, 180, 252) each having a tubular section (44, 146, 162, 268) and an elongated, axially rotatable, helically flighted screw section (56, 56a, 152, 168, 276, 278) which cooperatively define frustoconical, outwardly diverging material flow paths (75, 160, 291) at constant or differing divergence angles of from about 1-11°. The use of diverging tubular sections (44, 146, 162, 268) and screw sections (56, 56a, 152, 168, 276, 278) permits the use of larger die plates (76, 118, 292) with an increased number of die openings (80, 124, 296). This allows significant increases in extrusion production rates. The die assemblies (20, 90, 130, 140, 180, 252) can be used in the production of a wide number of human foods or animal feeds, and particularly aquatic feeds of the floating or sinking variety.

Abstract: Improved extruded starch-bearing grain products (e.g., corn and wheat) are provided having relatively high cook values and low cold water viscosities. The products are prepared by initial preconditioning to partially cook the starting material(s), followed by low shear extrusion cooking, with a total STE/SME ratio of at least about 4.

Abstract: Improved processes are provided for the production of grain-based products and especially multi-grain chips. The preferred process makes use of a single mixture of dry ingredients containing respective starch fractions having different levels of gelatinization. The starting mixture is preconditioned and extruded so as to form the mixture but without any substantial additional gelatinization of the starches. Moisture is added to the mixture during both preconditioning and extruding such that the extrudate exhibits both different levels of gelatinization in the starches therein, and also has portions with different levels of moisturization.

Abstract: High-capacity extrusion die assemblies (20, 90, 130, 140, 180, 252) each having a tubular sections (44, 146, 162, 268) and an elongated, axially rotatable, helically flighted screw section (56, 56a, 152, 168, 276, 278) which cooperatively define frustoconical, outwardly diverging material flow paths (75, 160, 291) at constant or differing divergence angles of from about 1-11°. The use of diverging tubular sections (44, 146, 162, 268) and screw sections (56, 56a, 152, 168, 276, 278) permits the use of larger die plates (76, 118, 292) with an increased number of die openings (80, 124, 296). This allows significant increases in extrusion production rates. The die assemblies (20, 90, 130, 140, 180, 252) can be used in the production of a wide number of human foods or animal feeds, and particularly aquatic feeds of the floating or sinking variety.

Abstract: Improved extruders and methods for the extrusion cooking of comestible products such as human foods or animal feeds are provided wherein the products may be produced with very low specific mechanical energy (SME) inputs as compared with conventional processing. The methods preferably involve introduction of very high levels of steam into the extruder barrel (12) during processing, which concomitantly reduces necessary SME inputs required to achieve desired cook and expansion levels in the products. In accordance with the invention, fully-cooked pet foods can be fabricated with SME inputs of up to about 18 kWhr/T, whereas aquatic feeds can be fabricated with SME inputs of up to about 16 kWhr/T.

Abstract: An improved, dual-shaft preconditioner (10, 70, 102) is provided having independent drive mechanism (18, 20, 78, 80) operatively coupled with a corresponding preconditioner shaft (14, 16, 74, 76, 106, 108) and permitting selective rotation of the shafts (14, 16, 74, 76, 106, 108) at rotational speeds and directions independent of each other. Preferably, the speed differential between the shafts (14, 16, 74, 76, 106, 108) is at least about 5:1. The mechanisms (18, 20, 78, 80) are operatively coupled with a digital control device (60) to allow rotational speed and direction control. Preferably, the preconditioner (10, 70, 102) is supported on load cells (62, 100) also coupled with control device (60) to permit on-the-go changes in material retention time within the preconditioner (10, 70, 102).

Abstract: A knife assembly (10) particularly adapted for coupling with an extruder barrel (26) is provided having a knife shaft (16) supporting a knife unit (14), with the knife shaft (16) axially rotatable and axially shiftable through fore and aft limits. The assembly (10) may be adjusted during operation without interrupting the axially rotation of shaft (16), using adjustment mechanism (24) located in a safely remote position from knife unit (14). The preferred assembly (10) includes axial shift limiting structure (114, 116, 124) serving to limit the extent of fore and aft axial movement of shaft (16). The mechanism (24) allows fine adjustment of the position of knife unit (14) relative to the extruder barrel (26), and also permits monitoring of the wear of knife unit (14).

Abstract: High-capacity extrusion die assemblies (20, 90, 130, 140, 180, 252) each having a tubular sections (44, 146, 162, 268) and an elongated, axially rotatable, helically flighted screw section (56, 56a, 152, 168, 276, 278) which cooperatively define frustoconical, outwardly diverging material flow paths (75, 160, 291) at constant or differing divergence angles of from about 1-11°. The use of diverging tubular sections (44, 146, 162, 268) and screw sections (56, 56a, 152, 168, 276, 278) permits the use of larger die plates (76, 118, 292) with an increased number of die openings (80, 124, 296). This allows significant increases in extrusion production rates. The die assemblies (20, 90, 130, 140, 180, 252) can be used in the production of a wide number of human foods or animal feeds, and particularly aquatic feeds of the floating or sinking variety.

Abstract: High-capacity extrusion die assemblies (20, 90, 130, 140, 180, 252) each having a tubular sections (44, 146, 162, 268) and an elongated, axially rotatable, helically flighted screw section (56, 56a, 152, 168, 276, 278) which cooperatively define frustoconical, outwardly diverging material flow paths (75, 160, 291) at constant or differing divergence angles of from about 1-11°. The use of diverging tubular sections (44, 146, 162, 268) and screw sections (56, 56a, 152, 168, 276, 278) permits the use of larger die plates (76, 118, 292) with an increased number of die openings (80, 124, 296). This allows significant increases in extrusion production rates. The die assemblies (20, 90, 130, 140, 180, 252) can be used in the production of a wide number of human foods or animal feeds, and particularly aquatic feeds of the floating or sinking variety.

Abstract: Improved, high Specific Mechanical Energy extrusion systems (20) are provided including a single or twin extruder (22) and an upstream preconditioner (24). The extruder (22) includes an elongated barrel (26) with at least one elongated, axially flighted, rotatable screw assembly (58) therein. The barrel (26) includes a mid-barrel variable restriction valve assembly (32), and the screw assembly (58) has a disrupting/homogenizing screw section (66) therein upstream of the valve assembly (32). The screw section (66) includes a plurality of alternating pitch screw parts (82-92). Preferably, the barrel (26) also has an atmospheric vent (36) downstream of the valve assembly (32).

Abstract: High-capacity extrusion die assemblies (20, 90, 130, 140, 180, 252) each having a tubular sections (44, 146, 162, 268) and an elongated, axially rotatable, helically flighted screw section (56, 56a, 152, 168, 276, 278) which cooperatively define frustoconical, outwardly diverging material flow paths (75, 160, 291) at constant or differing divergence angles of from about 1-11°. The use of diverging tubular sections (44, 146, 162, 268) and screw sections (56, 56a, 152, 168, 276, 278) permits the use of larger die plates (76, 118, 292) with an increased number of die openings (80, 124, 296). This allows significant increases in extrusion production rates. The die assemblies (20, 90, 130, 140, 180, 252) can be used in the production of a wide number of human foods or animal feeds, and particularly aquatic feeds of the floating or sinking variety.

Abstract: High-capacity extrusion die assemblies (20, 90, 130, 140, 180, 252) each having a tubular sections (44, 146, 162, 268) and an elongated, axially rotatable, helically flighted screw section (56, 56a, 152, 168, 276, 278) which cooperatively define frustoconical, outwardly diverging material flow paths (75, 160, 291) at constant or differing divergence angles of from about 1-11°. The use of diverging tubular sections (44, 146, 162, 268) and screw sections (56, 56a, 152, 168, 276, 278) permits the use of larger die plates (76, 118, 292) with an increased number of die openings (80, 124, 296). This allows significant increases in extrusion production rates. The die assemblies (20, 90, 130, 140, 180, 252) can be used in the production of a wide number of human foods or animal feeds, and particularly aquatic feeds of the floating or sinking variety.

Abstract: Improved, high Specific Mechanical Energy extrusion systems (20) are provided including a single or twin extruder (22) and an upstream preconditioner (24). The extruder (22) includes an elongated barrel (26) with at least one elongated, axially flighted, rotatable screw assembly (58) therein. The barrel (26) includes a mid-barrel variable restriction valve assembly (32), and the screw assembly (58) has a disrupting/homogenizing screw section (66) therein upstream of the valve assembly (32). The screw section (66) includes a plurality of alternating pitch screw parts (82-92). Preferably, the barrel (26) also has an atmospheric vent (36) downstream of the valve assembly (32).

Abstract: Improved single screw extruders systems (40) are provided including a single screw extruder (42, 92) as well as an upstream preconditioner (44). The extruders (42, 92) include a single, internal, elongated, helically flighted, axially rotatable screw assembly (52) having one or more improved screw sections (74, 74a, 76). The screw sections (74, 74a, 76) include specially configured flighting (86) wherein adjacent flighting portions (86a, 86b) have smoothly arcuate surfaces (88) extending between the respective flighting portion peripheries (90a, 90b). This flighting design provides smooth, substantially surge-free operation while increasing SME and cook values. The preferred preconditioner (44) has independently controlled mixing shafts (106, 108) allowing the shafts (106, 108) to be rotated at different rotational speeds and/or directions.

Abstract: Improved extruders and methods for the extrusion cooking of comestible products such as human foods or animal feeds are provided wherein the products may be produced with very low specific mechanical energy (SME) inputs as compared with conventional processing. The methods preferably involve introduction of very high levels of steam into the extruder barrel (12) during processing, which concomitantly reduces necessary SME inputs required to achieve desired cook and expansion levels in the products. In accordance with the invention, fully-cooked pet foods can be fabricated with SME inputs of up to about 18 kWhr/T, whereas aquatic feeds can be fabricated with SME inputs of up to about 16 kWhr/T.