Co-extrusion of food material and product resulting thereof

1. A system for dosing a food product onto a support comprising:

a dosing device for co-extruding at least two food materials at the same time to form a multi-component food product, the dosing device comprising

a static core element housing at least a first and a second supply, the first supply having at least one orifice connected to an extrusion channel which is positioned coaxially to an extrusion channel connected to an orifice of the second supply; and

a cylindrical tube element rotatable relative to and enclosing the core element, having a plurality of apertures distributed over an entirety of a circumference of the tube element, the apertures designed to be selectively brought into a coaxial position to the extrusion channels of the first and second supplies by rotating the cylindrical tube element, allowing a co-extrusion of food materials to be introduced into the first and second supplies of the core element, the first and second supplies in the tube element are cylinders that differ in diameter and are arranged co-parallel to the longitudinal axis of the core element and to each other and perpendicular to the extrusion channels.

2. The dosing system of claim 1 , wherein the core element houses a third supply, the third supply has at least one extrusion channel coaxially positioned to the extrusion channels of the first and second supplies, and the extrusion channels differ in diameter such that the extrusion channel of the first supply is placed within the extrusion channel of the second supply which is placed within the extrusion channel of the third supply.

3. The dosing system of claim 1 , wherein the lengths of the extrusion channels connected to the first and second supplies is such that an outlet of the extrusion channel connected to the first supply is positioned at a distance (L 1 ) from an outlet of the extrusion channel connected to the second supply.

4. The dosing system of claim 3 , wherein the distance (L 1 ) is equal or greater than 1 mm.

5. The dosing system of claim 1 , wherein the supplies are horizontally aligned so that the longitudinal axes of the supplies are co-parallel with the longitudinal axis of the core element.

6. The dosing system of claim 1 , wherein at least one of the extrusion channels is detachably connected to the orifice of the corresponding supply.

7. The dosing system of claim 1 , wherein at least one of the extrusion channels is closed.

8. The dosing system of claim 1 , wherein the tube element includes a plurality of apertures located over its circumference such that they can be aligned with at least one of the extrusion channels.

9. The dosing system of claim 8 , wherein each aperture of the tube element is equipped with a nozzle, the nozzles being connected to the tube element in a detachable manner or being integrally formed within the tube element.

10. The dosing system of claim 9 , wherein the dimension of at least one of the nozzles or the cross section of an opening of the nozzles is different for each nozzle.

11. The dosing system of claim 10 , wherein the nozzles comprise teeth of a different shape which project towards the centre axis of the openings.

12. The dosing system of claim 11 , wherein the teeth of the nozzles are formed so as to project in the direction of the food product flow dosed by the dosing device.

13. The dosing system of claim 1 , wherein delivering means are connected to the first and second supplies of the dosing device for providing a flow of food product to the device, and controlling means for controlling the flow of food product.

14. The dosing system of claim 1 , wherein the system comprises a support onto which the food product is dosed, the support being static or relatively movable to the dosing device in a continuous or intermittent manner.

15. The dosing system of claim 14 , wherein the support is a conveyor belt.

16. The dosing system of claim 15 , wherein the conveyor belt has a chilled surface.

17. The dosing system of claim 14 , wherein at least one object is carried by the support.

18. The dosing system of claim 17 , wherein the object is selected from the group consisting of a tray, a moulding surface and a food product.

19. The dosing system of claim 1 , wherein the system is provided with drive means for rotating the tube element about its longitudinal axis.

20. The dosing system of claim 1 , wherein the tube element comprises a plurality of apertures, and the apertures are designed to be selectively brought into a coaxial position to the extrusion channels of the first and second supplies by continuously rotating the cylindrical tube element.

21. The dosing system of claim 20 , wherein the tube element allows a continuous co-extrusion of portioned food materials introduced into the first and second supplies of the core element.

22. The dosing system of claim 1 , further comprising cylindrical recesses distributed over the circumference of the tube element and aligned with the apertures.

23. The dosing system of claim 1 , wherein each of the extrusion channels comprises an outlet at an opposite end of the extrusion channel from the corresponding supply, and the extrusion channel of the first supply extends perpendicularly from the first supply through one side of the second supply to an opposite side of the second supply and into the extrusion channel of the second supply such that the second supply is between the first supply and the outlet of the extrusion channel of the first supply, in a radial direction relative to the longitudinal axis of the core element.

24. The dosing system of claim 1 , wherein the extrusion channel of the first supply extends through the orifice in the second supply.