A compression system includes a compression device and a controller. A treated material is pressed longitudinally through a compression chamber by simultaneously applying a lateral pressure and a two-dimensional cross-section compression which includes a pressure applied in a direction traverse to a direction of transport and a pressure applied in a direction parallel to the direction of transport. The controller controls the two-dimensional cross-section compression applied to the treated material such that, during compression, liquids in the treated material migrate to the outer surface of the treated material upon reaching the outlet orifice.

An extruder (100) for comestible material comprises a tubular barrel (104) and one or more elongated, axially rotatable, helically flighted screws (120, 122) within the barrel (104), where the barrel (104) has a delivery opening (114a). The extruder barrel (104) is equipped with an assembly (22) for delivery of fluid to the interior thereof, including a static mixing section (54) operable to blend the steam and water to create a blended mixture; the blended mixture is delivered to the barrel opening (114a) by means of a conveying assembly (84, 86) having a pipe assembly (86) with an outlet in communication with the barrel opening (114a); the pipe assembly (86) and opening (114a) have diameters less than maximum internal diameter of the static mixer casing (72).

A method for extruding a comestible material comprises the steps of passing comestible material into an extruder (100) with rotation of the extruder screw(s) (120, 122) and delivery of fluid comprising steam and water into an opening (114a) of the extruder barrel (104). The fluid delivery step comprises separately directing individual quantities of steam and water into the casing (72) of a static mixing section (54), and blending the steam and water to create a blended mixture, and then delivering the blended mixture into the barrel (114a). The blended mixture is delivered to the barrel opening (114a) by means of a conveying assembly (84, 86) having a pipe assembly (86) with an outlet in communication with the barrel opening (114a); the pipe assembly (86) and opening (114a) have diameters less than maximum internal diameter of the static mixer casing (72).

Described herein are chewable articles intended to be provided to animals for purposes including dental cleaning, breath freshening, nutrition, administration to the animal of beneficial agents, satisfaction of the animal's urge to chew, and general enjoyment by the animal. Also disclosed are apparatus and methods for making such chewable articles, the methods including the use of a processing aid to lubricate the article-forming apparatus, such as extruders, portioners, and molds, and to reduce the power requirements of such apparatus in the forming process.

Apparatus (20) for injection of fluid into extrusion system components such as a preconditioner (24) or extruder (100) is provided, preferably as a composite assembly including a fluid injection valve (52) and an interconnected static mixer section (54). Alternately, use may be made of the fluid injection valve (52) or static mixer section (54) alone. The invention greatly simplifies the fluid injection apparatus used in extrusion systems, while giving more efficient absorption of thermal energy with a minimum of environmental contamination, and the ability to inject multiple streams into the extrusion systems.

A method for extruding a comestible material comprises the steps of passing comestible material into an extruder (100) with rotation of the extruder screw(s) (120, 122) and delivery of fluid comprising steam and water into an opening (114a) of the extruder barrel (104). The fluid delivery step comprises separately directing individual quantities of steam and water into the casing (72) of a static mixing section (54), and blending the steam and water to create a blended mixture, and then delivering the blended mixture into the barrel (114a). The blended mixture is delivered to the barrel opening (114a) by a conveying assembly (84, 86) having a pipe assembly (86) with an outlet in communication with the barrel opening (114a); the pipe assembly (86) and opening (114a) have diameters less than maximum internal diameter of the static mixer casing (72).

An extruder (100) for comestible material comprises a tubular barrel (104) and one or more elongated, axially rotatable, helically flighted screws (120, 122) within the barrel (104), where the barrel (104) has a delivery opening (114a). The extruder barrel (104) is equipped with an assembly (22) for delivery of fluid to the interior thereof, including a static mixing section (54) operable to blend steam and water to create a blended mixture; the blended mixture is delivered to the barrel opening (114a) by of a conveying assembly (84, 86) having a pipe assembly (86) with an outlet in communication with the barrel opening (114a); the pipe assembly (86) and opening (114a) have diameters less than maximum internal diameter of the static mixer casing (72).

An animal feed producing system comprises a compression screw assembly. The compression screw assembly includes at least a first screw, a second screw and a plurality of barrels. The first and second screws include a plurality of flights and roots. The plurality of screws is configured such that they include a plurality of sections. Each section comprises a set of plurality of flights and a plurality of roots configured to perform a specific compression function, such as perpendicular compression and lateral compression.

Methods of preconditioning comestible materials such as foods or feeds include the step of separately injecting steam and water into a static mixer in order to create a blend, which is then injected into the materials within a preconditioner barrel. The methods yield increased cook values in the preconditioned materials, with a reduction in evolved steam from the preconditioner.

Described herein are chewable articles intended to be provided to animals for purposes including dental cleaning, breath freshening, nutrition, administration to the animal of beneficial agents, satisfaction of the animal's urge to chew, and general enjoyment by the animal. The chews are made to be appetizing to the animal, to satisfy an urge to chew, to effect abrasive cleaning of the animal's teeth, to deliver one or more active agents to the oral cavity of the animal, or a combination of these. The chews have a resilient, chewable texture and are shaped to facilitate dental cleaning, to facilitate oral grasping by the animal, to appeal to human owners of the animal, to enhance the human-animal bond, or a combination of these. Also disclosed are apparatus and methods for making such chewable articles and for formulating and using them to effect dental health in animals.