WO2008093367A1

WO2008093367A1 - System for pasteurising foodstuffs

Info

Publication number: WO2008093367A1
Application number: PCT/IT2007/000060
Authority: WO
Inventors: Dino Veronesi
Original assignee: Verinox S.P.A.
Priority date: 2007-01-30
Filing date: 2007-01-30
Publication date: 2008-08-07

Abstract

A system for pasteurising foodstuffs comprises: a pasteurising chamber (3); a cooling station (7); means (13) for feeding foodstuffs (2) towards the chamber (3); means (14) for inserting the foodstuffs (2) in the chamber (3); means (18) for extracting the foodstuffs (2) from the chamber (3); means (19) which feed the foodstuffs (2) forward through the cooling station (7); means for supplying steam in the pasteurising chamber (3); means (26) for spraying water on the foodstuffs (2) in the cooling station (7); and at least one system (1) operation electronic control system. The electronic system is programmed to carry out in sequence the operating steps of inserting a plurality of foodstuffs (2) in the chamber (3), supplying steam at a temperature of between 100°C and 120°C in the pasteurising chamber (3) to create an overpressure in the chamber relative to the environment, greater than 0.01 bar and less than 0.5 bar, and a relative humidity of between 22 and 99%.

Description

System for pasteurising foodstuffs

Technical Field

The present invention relates to a system for pasteurising foodstuffs, and in particular a system for pasteurising packaged hams and dressed pork products.

Disclosure of the Invention

Although there are currently various prior art methods for pasteurising packaged hams and dressed pork products, the technical purpose which forms the basis of the present invention is to produce a system for pasteurising foodstuffs which allows the achievement of better performance than with existing systems.

In particular the technical purpose of the present invention is to produce a system for pasteurising foodstuffs which guarantees a high speed of penetration of the temperature in the foodstuff, and greater safety in killing off the most common pathogens such as salmonella, colon bacilli and listeria. The technical purpose specified and the aims indicated are substantially achieved by a system for pasteurising foodstuffs as described in the claims herein.

Brief Description of the Drawings

Further features and advantages of the present invention are more apparent in the detailed description below, with reference to several preferred, non-limiting embodiments of a system for pasteurising foodstuffs, illustrated in the accompanying drawings, in which:

Figure 1 is a schematic plan view of a system made in accordance with the present invention;

Figure 2 is a perspective top view of a structure for supporting foodstuffs to be pasteurised which can be used in the system of Figure 1;

Figure 3 is a vertical cross-section of a pasteurising chamber of a system made in accordance with the present invention;

Figure 4 is a vertical cross-section of a cooling station of a pasteurising system made in accordance with the present invention;

Figures 5 to 8 are front views of the detail of the upper part of the structure of Figure 2 at different sections of the system (feeding zone, pasteurising chamber, first cooling sub- station, second cooling sub-station) ;

Figure 9 is a schematic top view of an embodiment of a system made in accordance with the present invention showing the initial and final parts of the forward feed path for the foodstuffs in the system; Figures 10 and 11 are enlarged views respectively of the details X ad XI of Figure 9;

Figure 12 is a schematic lateral cross-section of the pasteurising chamber and the cooling station of a pasteurising system made in accordance with the present invention; Figure 13 is a vertical cross-section of the detail of the hooking of the structure of Figure 2 to the rest of the system at a first cooling sub-station; "

Figures 14 and 15 are enlarged views respectively of the details XIV and XV of Figure 12; Figure 16 is a perspective view with some parts cut away of a detail of the forward feed system for the supporting structures in the second cooling sub-station;

Figure 17 is a perspective top view with some parts cut away of a detail of a first part of the cooling station; Figure 18 is a perspective view with some parts cut away of a detail of the forward feed system for the supporting structures upstream of the pasteurising chamber; and

Figure 19 is a schematic lateral cross-section of a another embodiment of a pasteurising system made in accordance with the present invention.

Detailed Description of the Preferred Embodiments of the Invention With reference to the accompanying drawings, the numeral 1 denotes as a whole a system for pasteurising foodstuffs 2 made in accordance with the present invention.

In accordance with the present invention, the system 1 for pasteurising foodstuffs 2 comprises at least one pasteurising chamber 3 with at least one opening 4, 5 and with closing means 6 for sealing closed the opening 4, 5, and at least one cooling station 7 into which the foodstuffs 2 are brought once the treatment in the pasteurising chamber 3 is complete. In the embodiment illustrated in Figure 3, the pasteurising chamber 3 is delimited internally by a substantially cylindrical wall 8 which, thanks to its shape, allows it to better withstand the overpressures generated- in the pasteurising chamber 3.

-The chamber closing means 6 may, for example, comprise either at least one swing door 9 preferably able to open towards the inside of the pasteurising chamber 3 (as in the case in Figure 1 where there are two doors 9 each having two wings) , or a sliding door 10 (as in the case in Figure 19 where the doors are of the type which move vertically) . In the preferred embodiments the pasteurising chamber 3 has a first, foodstuffs 2 inlet opening 4 and a second, foodstuffs 2 outlet opening 5, both fitted with closing means 6. The system 1 preferably has a linear foodstuffs 2 forward feed path along which the pasteurising chamber 3 and the cooling station 7 are located one after another.

The cooling station 7 may in turn be divided into a number of sub-stations (a first sub-station 11 and a second sub-station 12 in Figure 12), each preferably able to house a number of foodstuffs 2 substantially corresponding to that which can be housed in the pasteurising chamber 3, since the time needed for cooling the foodstuffs 2 is usually greater than that necessary for the pasteurising heat treatment.

The system 1 also comprises feeding means 13 for feeding a plurality of foodstuffs 2 towards the pasteurising chamber 3 and insertion means 14 for inserting the foodstuffs 2 in the pasteurising chamber 3 through the relative opening 4, 5 (first opening 4 in the accompanying drawings) . Movement means 15 allow the foodstuffs 2 to be moved once they have been inserted in the pasteurising chamber 3, and in particular, in the embodiment illustrated, at least from one inlet section 16 close to the first opening 4 to at least one outlet section 17 close to the second opening 5.

The system also has extracting means 18 designed to allow the foodstuffs 2 to be extracted from the pasteurising chamber 3 through the relative opening 4, 5 (second opening 5 in the accompanying drawings) and forward feed means 19 which allow the foodstuffs 2 to be fed forward through the cooling station 7.

Finally, advantageously, pick up means 20 allow the foodstuffs 2 to be picked up from the cooling station 7 then sent on to other systems/departments. Moreover, in the embodiments illustrated, the pick up means 20 have a structural shape similar to that of the feeding means 13.

The structure of the various elements is examined in more detail below.

Supply means are associated with the pasteurising chamber 3 and allow steam to be supplied in the pasteurising chamber 3 at a predetermined temperature. Such supply means comprise a steam generator (of the known type and not illustrated) and a plurality of nozzles fed by the steam generator (by means of suitable first pipes 22) and distributed in the pasteurising chamber 3. Figure 3 shows a cross-section of the pasteurising chamber 3 in which it is possible to identify six different nozzles positioned symmetrically relative to the vertical longitudinal middle plane. There are two tangential main nozzles 23 positioned in the upper part of the pasteurising chamber 3 so as to supply the steam at a tangent to the wall of the--'chamber 3 and two tangential secondary nozzles 24 positioned in the lower part of the pasteurising chamber 3, also so as to supply the steam at a tangent to the wall of the chamber 3.

The pasteurising chamber 3 also comprises a showering circuit whose two central nozzles 25 are visible, positioned in the upper part of the pasteurising chamber 3 so as to spray cold water towards the foodstuffs 2 for depressurising the pasteurising chamber 3 at the end of the heating cycle. The arrangement illustrated in Figure 3 is repeated several times along the pasteurising chamber 3. The alignment of the main and secondary nozzles 23, 24 at a tangent to the wall of the pasteurising chamber 3, together with a suitable activation mode (intermittent), guarantees continuous mixing of the steam in the chamber 3.

In the preferred embodiments the cooling station 7 is a tunnel in which there are spraying means 26 for spraying water on the foodstuffs 2 inside it. As shown in Figure 4 (which is a vertical cross-section of the cooling station I)₁ the spraying means 26 comprise second pipes 27 which feed water to a plurality of nozzles 28. A collection system 29 recovers the water on the base of the cooling station 7 and puts it back into circulation using a suitable pumping unit 30. In the preferred embodiments the spraying means also comprise an evaporation tower recovery system to keep the temperature of the cooling water at a value not higher than 18 - 20⁰C. When said temperature is exceeded, the evaporation tower has a water - glycol heat exchanger added to it. Operation of the entire system 1 is managed by at least one electronic control system operatively connected to the various parts of the system 1 (not illustrated) .

In accordance with the present invention, the electronic system is programmed to carry out in sequence a first operating step of inserting a plurality of foodstuffs 2 in the pasteurising chamber 3 using the feeding means 13, a second operating step of closing the pasteurising chamber 3 with the sealing closing means 6, and a third operating step of supplying steam at a temperature of between 100⁰C and 120⁰C in the pasteurising chamber 3 using the ' supply means. Moreover, the supply of steam is controlled in such a way that an overpressure is created in the pasteurising chamber 3 relative to the environment, greater than 0.01 bar and less than 0.5 bar and with a rela-tive humidity of between 22 and 99%. Depending on the type of foodstuff to be pasteurised, the step of supplying steam lasts for a predetermined time.

At the end of the step of supplying steam (step of treatment in the pasteurising chamber 3), the electronic system is also programmed to feed the foodstuffs 2 forward along the cooling station 7 using the forward feed means 19 and to spray water, with the spraying means 26, on the foodstuffs 2 positioned along the cooling station 7 to cool them. Depending on the embodiments, the methods for moving the foodstuffs 2 may vary.

In particular, in the accompanying drawings two possible movement methods are illustrated, a direct movement of the foodstuffs 2 (Figure 19) and an indirect movement (Figures 1 - 18).

For the direct movem&n-fe, in general, the feeding means 13, the movement means 15 and the forward feed means 19 respectively comprise one or more first conveyors 31, one or more second conveyors 32 and one or more third conveyors 33 on which the foodstuffs 2 may be directly loaded.

In the embodiment in Figure 19, in particular, the conveyors 31, 32, 33 are repeated on four levels on top of one another.

Moreover, downstream of the forward feed means 19 the pick up means 20 comprise one or more fourth conveyors 34 similarly to the feeding means 13. Suitable loading and unloading devices 35, 36 (of the known type, therefore not illustrated in detail) allow foodstuffs 2 to be loaded on the feeding means 13 and unloaded from the pick up means 20.

Finally, it should be noticed that the insertion means 14 and extracting means operate in a way similar to those described below relative to the second foodstuffs 2 movement method.

The indirect movement of foodstuffs 2 involves the use of a plurality of movable supporting structures 37 on which the foodstuffs 2 are positioned and on which at least the feeding means 13, the movement means 15 and the forward feed means 19 act.

In the embodiment illustrated (Figure 2), the supporting structure 37 comprises a frame 38 on which a plurality of shelves

39 for foodstuffs 2 is mounted, and which has an upper hooking end

40. The latter can be operatively associated with at least the feeding means 13, movement means 15 and forward feed means 19 to allow the foodstuffs 2 to^e moved along the pasteurising system

1. The ,' supporting structure 37 is preferably suspended by the upper hooking end 40 so that, in practice, its lower part is raised off the ground (Figures..2 and 3) .

For this purpose, the supporting structure 37 has a plurality of idle wheels 41 (four in Figures 2, 16 and 18) mounted at the upper hooking end 40.

In particular, the upper hooking end 40 comprises a longitudinal element 42 centrally pivoting at the rest of the frame 38 (which is therefore free to rotate relative to the longitudinal element 42) having at each end two bars 43 extending upwards, at the top of each of which two idle wheels 41 are transversally pivoting on both sides.

Figures 5 to 8, Figure 13, Figure 16 and Figure 18 show how such supporting structures 37 interact with the feeding means 13, movement means 15 and forward feed means 19 to allow the foodstuffs 2 to be moved along the system 1.

As shown in Figures 5 and 18, the feeding means 13 comprise a guide 44 extending according to its own trajectory and on which the idle wheels 41 of the supporting structures 37 move, and a mechanism 45 for pushing the supporting structures 37 along the guide 44. As Figure 18 in particular shows, the guide 44 comprises two tracks 46 set side by side and distanced from one another, in the middle of which the two vertical bars 43 are inserted, and on which the idle wheels 41 rest.

The pushing mechanism 45 is schematically illustrated in Figures 9 and 18. It is a stepping mechanism which allows each supporting structure 37 to be fed forward by a predetermined distance each time it is activated. It comprises a plurality of engagement elements 47, distributed along the guide 44 extension trajectory, which can be moved in a synchronised fashion along the trajectory, each from a back position to a forward position. The pushing mechanism 45 is also sized in such a way that the distance between the back position and the forward position of each engagement element 47 is at least equal to the distance between one engagement element 47 and the next along the trajectory, so that a supporting structure 37 left at the forward position of one engagement element 47 can be hooked by the next engagement element From the structural viewpoint, each engagement element 47 comprises a supporting part 48 driven with a to and fro movement, and a movable part 49 associated with the supporting part 48. The movable part 49 moves with the supporting part 48, but may also move, relative to it, between a first position and a second position. When it is in the first position (Figure 18) the movable part 49 is transversal to the movement trajectory of the supporting structures 37, so that it can make contact with a supporting structure 37 (and in particular with its longitudinal element 42) located on the guide 44 at the movement zone of the engagement element 47 to which the movable part 49 belongs. In contrast, when it is in the second position (not illustrated) , the movable part 49 is rotated relative to the first position, and is practically aligned with the guide 44 for the supporting structures, so that it cannot make contact with supporting structures 37 hooked on the guide 44.

In the absence of external stresses, the movable part 49 is kept in the first position_^by suitable elastic return means (not illustrated) . When the movable part 49, in its first position, makes contact with a supporting structure 37 as illustrated in Figure 18 (that is to say, during movement of the engagement element 47 from the back position to the forward position) , it causes the supporting structure 37 to be pulled along the guide 44. In contrast, when the movable part 49, in its first position, makes contact with a supporting structure 37 during movement of the engagement element 47 from the forward position to the back position (that is to say on the opposite side to that illustrated in Figure 18), the reaction of the supporting structure 37 overcomes the resistance of the elastic return means and causes the movable part 49 to rofa'te/move from the first to the second position, consequently disengaging the engagement -element 47 from the supporting structure 37. In this way, the engagement element 47 which returns to the back position can "get over" the supporting structure 37 previously moved forward by the engagement element 47 immediately upstream of it.

Finally, the feeding means may also comprise mechanical stops (not illustrated) associated one with the back position of each engagement element 47 to prevent the supporting structures 37 from continuing their forward and/or backward movement due to any unfavourable gradients. Advantageously, the pick up means 20 downstream of the cooling station 7 (not illustrated) may also have a similar configuration. However, as shown in Figure 11 (in two different positions), the pick up means 20 also comprise a pulling tooth 50 which can be operated witn"'a to and fro motion by means of a specific first actuator 51, able to unload the supporting structures from the forward feed means 19.

As shown in Figure 9, the feeding means 13 may comprise means 52 for orientation of the supporting structures 37 which allow the structures to be oriented in the most suitable way for their entry in the pasteurising chamber 3. In particular, in the embodiment illustrated, the orientation means 52 allow first orientation of the supporting structures 37 longitudinally along the guide 44 then again transversally to it. Longitudinal orientation is achieved by means of a fixed guide element 53 (Figure 9), whilst subsequent transversal orientation is achieved with a suitable cylinder 54 (Figure 10] . In both cases, it is the frame 38 of the supporting structures 37 which rotates relative to its upper hooking end 40 (therefore about an axis of rotation which is in practice vertical, indicated with a dotted and dashed line in Figure 2) .

The movement means 15 and forward feed means 19 respectively comprise at least a first pulling chain 55 and a second pulling chain 56 designed to feed forward the supporting structures 37 on which the foodstuffs 2 are supported. In particular, the movement means 15 and the forward feed means 19 respectively comprise at least two first chains 55 parallel with one another and two second chains 56 parallel with one another (distanced from one another like the tacks 46 of the feeding means 13 described-atoove - Figures 13 and 16) . As shown in Figure 15 relative to the cooling station 7, there may also be two or more pairs of first chains 55 and second chains 56 positioned one after another. Figures 10, 12, 14, 15 and 17 schematically illustrate the insertion means 14 and the extracting means 18.

In the preferred embodiment, the insertion means 14 allow the reciprocal movement of at least part of the feeding means 13 and/or the movement means 15 in such a way that the movement means 15 can directly pick 'up the foodstuffs 2 unloaded by the feeding means 13. In other words, the insertion means 14 are able to move at least part of the feeding means 13 and/or the movement means 15 respectively towards the movement means 15 and the feeding means 13, through the openings in the pasteurising chamber 3. In the embodiment illustrated, in particular, the insertion means 14 comprise a portion 57 of.,, the feeding means 13 which is telescopically movable between a retracted position in which it is outside the pasteurising chamber 3 (position indicated with a continuous line in Figure 10) and an extended position in which it is inserted in the pasteurising chamber 3 through the first opening 4 (position indicated with a dashed line in Figure 10) and draws near to the movement means 15. Movement of the telescopic portion 57 is guaranteed by two second actuators 58. Pneumatic pushers (not illustrated) allow movement of the supporting structures 37 on the telescopic portion 57 in the extended position and their loading on the first chains 55.

Alternatively, the insertion means 14 may comprise a similar portion of the movement means 15 movable between a retracted position in which it is Tri¹" the pasteurising chamber 3 and an extended position in which it projects outside the pasteurising chamber 3 through the first opening 4 to draw near to the feeding means 13 (solution not illustrated) .

The extracting means 18 can allow reciprocal movement of at least part of the movement means 15 and/or the forward feed means 19 in such a way that the forward feed means 19 can directly pick up the foodstuffs 2 unloaded by the movement means 15. In particular, in the embodiment illustrated, the extracting means 18 comprise a portion 59 of the forward feed means 19 movable between a retracted position in which it is outside the pasteurising chamber 3 (indicated with a continuous line in Figures 12, 14 and 15) and an extended position in which it is inserted in the pasteurising chamber 3 through the second opening 5 (indicated with a dashed line in Figures 12, 14 and 15) .

In more detail, it is the entire portion 59 of the forward feed means 19 positioned at the first cooling 7 sub-station 11. As shown in Figure 17, at the first sub-station 11, the forward feed means 19 are supported by a secondary structure 60 having the shape of a carriage and equipped with a plurality of wheels 61 mounted on a main structure 62 of the cooling station 7. Correct positioning of the forward feed means 19 is guaranteed by a rack 63 integral with the secondary structure 60 meshing with a motor- driven gearwheel 64 mounted on the main structure 62 and controlled by the electronic control system.

Similarly, the extracting means 18 may comprise a portion of the movement means 15 movable between a retracted position in which it is in the pasteurising chamber 3 and an extended position in which it projects outside, the pasteurising chamber 3 through the second opening 5 and is in contact with the forward feed means 19.

Operation of the system 1 disclosed is, as already indicated, controlled directly by the electronic control system.

With reference to the embodiment in Figures 1 to 18, each batch of foodstuffs 2 to be pasteurised (where the term batch indicates the quantity of foodstuffs 2 which can simultaneously be inserted in the pasteurising chamber 3) is loaded on a plurality of supporting structures 37 which are hooked one after another by the feeding means 13, one for each engagement element 47. As the feeding means 13 move forwards the supporting structures 37 are oriented first longitudinally and then transversally by the orientation means 52. At this point, thanks to the insertion means 14, the feeding means 13 are brought into operating contact with the movement means 15 and the supporting structures 37 are pushed one after another onto the first chains 55 which in the meantime move forward one predetermined step after loading each supporting structure 37. When the pasteurising chamber 3 is full, the insertion means 14 return to their home condition and the closing means 6 close the chamber . The control system then activates the supply means which supply steam in the pasteurising chamber 3 until a predetermined temperature, pressure and relative humidity in the range indicated above are established. When the heat treatment is complete, the overpressure in the chamber is eliminated and the closing means 6 open the first and the second opening 5.

The extracting means 18 then bring the forward feed means 19 into operative contact with the movement means 15 and the synchronised forward movement of the first and second chains 56 causes the transfer of the supporting structures 37 from the movement means 15 to the forward feed means 19.

When, as shown in Figure 12, the cooling station 7 is divided into two sub-stations and the extracting means 18 only affect the first sub-station 11, during the treatment of a batch of foodstuffs 2 in the pasteurising chamber 3, the previous batch is transferred from the first sub-station 11 to the second substation 12 which in the meantime is emptied of the foodstuffs 2 present in it. When a batch is in _^the second sub-station 12 and has completed the cooling cycle, the second chains 56 cause it to move forward in such a way as to transfer it onto the pick up means 20 which carry it away from the pasteurising system 1.

The present invention brings important advantages. The system disclosed guarantees a high speed of penetration of the temperature in the foodstuff and greater safety in killing off the most common pathogens such as salmonella, colon bacilli and listeria.

Moreover, the system disclosed has a high level of productivity.

It should also be noticed that the present invention is relatively easy to produce and even the cost linked to implementation of the invention is not very high.

The invention described may be modified and adapted in several ways without thereby departing from the scope of the inventive concept .

All details of the invention may be substituted by other technically equivalent elements and, in practice, all of the materials used, as well as the shapes and dimensions of the various components, may be any according to requirements.

Claims

1. A system for pasteurising foodstuffs, characterised in that it comprises: at least one pasteurising chamber (3) having at least one opening (4), (5) and closing means (6) for sealing closed the opening (4), (5) ; at least one cooling station (7) ; feeding means (13) for feeding a plurality of foodstuffs (2) towards the pasteurising chamber (3) ; insertion means (14) for inserting the foodstuffs (2) fed by the feeding means (13) in the pasteurising chamber (3) through the opening (4), (5) ; movement means (15) for moving the foodstuffs (2) in the pasteurising chamber (3); extracting means' (18) for allowing the foodstuffs (2) to be extracted from the pasteurising chamber (3) ; forward feed means (19) to feed the foodstuffs (2) forward out of the pasteurising chamber (3) through the cooling station (7); supply means for supplying steam in the pasteurising chamber (3); spraying means (26) for spraying water on the foodstuffs (2) at the cooling station (7); at least one system (1) operation electronic control system operatively connected to the various parts of the system (1) ; the electronic systenu-.being programmed to carry out in sequence the following operating steps: inserting a plurality of foodstuffs (2) in the pasteurising chamber (3) using the feeding means (13); closing the pasteurising chamber (3) using the sealing closing means (6); supplying, using the supply means, steam at a temperature of between 100⁰C and 120°C in the pasteurising chamber (3) to create an overpressure in it relative to the environment greater than

0.01 bar and less than 0.5 bar and a relative humidity of between 22 and 99%.

2. The pasteurising system according to claim 1, characterised in that the electronic system is programmed to carry out the step of supplying steam for a predetermined time interval.

3. The pasteurising system according to claim 1 or 2, characterised in that the electronic system is also programmed to subsequently carry out the following operating steps: feed the foodstuffs (2) forward along the cooling station (7) using the forward feed means (19); and spray water on the foodstuffs (2) in the cooling station (7) to cool them using the spraying means (26) .

4. The pasteurising system according to any of the foregoing claims, characterised in that it also comprises a plurality of movable supporting structures (37) for the foodstuffs (2), at least the feeding means (13) , movement means and forward feed means acting on the support-ing structures (37).

5. The pasteurising system according to claim 4, characterised in that the supporting structure (37) comprises a frame (38) and a plurality of shelves (39) mounted on the frame (38) .

6. The pasteurising system according to claim 5, characterised in that the frame (38) has an upper hooking end (40) which can be operatively associated with at least the feeding means (13) , movement means and forward feed means .

7. The pasteurising system according to claim 6, characterised in that in practice the supporting structure (37) is raised off the ground.

8. The pasteurising system according to any of the claims from 4 to 7, characterised in that the supporting structure (37) has a plurality of idle wheels (41) designed to allow it to be fed forward.

9. The pasteurising system according to claim 8, characterised in that the feeding means (13) comprise a guide (44) extending according to its ^'own trajectory and with which the idle wheels (41) engage, and a mechanism (45) for pushing the supporting structures (37) along the guide (44).

10. The pasteurising system according to claim 9, characterised in that the pushing mechanism (45) is a stepping mechanism.

11. The pasteurising system according to claim 10, characterised in that the pushing mechanism (45) comprises a plurality of engagement elements (47) distributed along the guide (44) extension trajectory and able to move along the trajectory in a synchronised fashion, each from a back position to a forward position, the distance between the back position and the forward position of each engagement element (47) being at least equal to the distance between one engagement element (47) and the next along the trajectory.

12. The pasteurising system according to claim 11, characterised in that each engagement element (47) comprises a supporting part (48) and a movable part (49) associated with the supporting part (48) and able to move between a first position in which it is positioned in such a way that it makes contact with a supporting structure (37) located on the guide (44) at the engagement element (47) movement zone, and a second position in which it cannot make contact with such a supporting structure (37), there being elastic return means to hold the movable part (49) in the first position in the absence of external stresses, contact between the movable part (49), in the first position, and a supporting structure (37), during engagement element (47) movement from the back position to the forward position causing the supporting structure (37) to be pulled along the guide (44), and contact between the movable part (49), in the first position, and a supporting structure (37) during engagement element (47) movement from the forward position to the back position causing the movable part (49) to move to its second position and consequent disengagement of the engagement element (47) from the supporting structure (37).

13. The pasteurising system according to any of the claims from 4 to 12, characterised in that the feeding means (13) also comprise orientation means (52) for the supporting structures (37) .

14. The pasteurising system according to claim 13, characterised in that the supporting structures (37) can rotate relative to their own fixed portion, according to an axis of rotation which is in practice vertical.

15. The pasteurising system according to any of the claims from 4 to 14, characterised in that the movement means (15) comprise at least a first pulling chain (55) designed to feed forward the supporting structures (37) on which the foodstuffs (2) are positioned.

16. The pasteurising system according to any of the claims from 4 to 15, characterised in that the forward feed means (19) comprise at least a second pulling chain (56) designed to feed forward the supporting structures (37) on which the foodstuffs (2) are positioned.

17. The pasteurising system according to any of the claims from 1 to 3, characterised in that the feeding means (13) comprise one or more first conveyors (31) on which the foodstuffs (2) can be loaded.

18. The pasteurising system according to claim 17, characterised in that the movement means (15) comprise one or more second conveyors, (32) on which the foodstuffs (2) can be loaded.

19. The pasteurising system according to claim 18, characterised in that the forward feed means (19) comprise one or more third conveyors (33) on which the foodstuffs (2) can be loaded.

20. The pasteurising system according to any of the foregoing claims, characterised in thafe it also comprises means (20) for picking up the foodstuffs (2) from the cooling station (7) .

21. The pasteurising system according to claim 20, characterised in that the pick up means (20) have a structural shape similar to that of the feeding means (13) .

22. The pasteurising system according to any of the foregoing claims, characterised in that the insertion means (14) allow the reciprocal movement of at least part of the feeding means (13) and/or the movement means (15) so that the movement means (15) can directly pick up the foodstuffs (2) unloaded by the feeding means (13).

23. The pasteurising system according to claim 22, characterised in that the insertion means (14) comprise a portion of the feeding means (13) movable between a retracted position in which it is ■ outside the pasteurising chamber (3) and an extended position in which it is inserted in the pasteurising chamber (3) through the opening (4) , (5) .

24. The pasteurising system according to claim 22, characterised in that the insertion means (14) comprise a portion of the movement means (15) movable between a retracted position in which it is in the pasteurising chamber (3) and an extended position in which it projects outside the_a pasteurising chamber (3) through the opening (4) , (5) .

25. The pasteurising system according to any of the foregoing claims, characterised in that the extracting means (18) allow the reciprocal movement of at least part of the movement means (15) and/or the forward feed means (19) so that the forward feed means (19) can directly pick up the foodstuffs (2) unloaded by the movement means (15) .

26. The pasteurising system according to claim 25, characterised in that the extracting means (18) comprise a portion of the forward feed means (19) movable between a retracted position in which it is outside the pasteurising chamber (3) and an extended position in which it . is inserted in the pasteurising chamber (3) through the opening (4), (5).

27. The pasteurising system according to claim 25, characterised in that the extracting means (18) comprise a portion of the movement means (15) movable between a retracted position in which it is in the pasteurising chamber (3) and an extended position in which it projects outside the pasteurising chamber (3) through the opening (4) , (5) .

28. The pasteurising system according to any of the foregoing claims, characterised in that the pasteurising chamber (3) has a first opening (4) through which the insertion means (14) act, and a second opening (5) through which the extracting means (18) act, the closing means (6) acting—on both openings.

29. The pasteurising system according to claim 28, characterised in that the movement means (15) allow the foodstuffs (2) to be fed forward in the pasteurising chamber (3) at least from one inlet section (16) close to the first opening (4) to at least one outlet section (17) close to the second opening (5) .

30. The pasteurising system according to any of the foregoing claims, characterised in that the pasteurising chamber (3) closing means (6) comprise at least one door having at least one wing which can open towards the inside of the pasteurising chamber (3) .

31. The pasteurising system according to any of the claims from 1 to 29, characterised in that the pasteurising chamber (3) closing means (6) comprise at least one sliding door.

32. The pasteurising system according to any of the foregoing claims, characterised in that the cooling station (7) is divided into two sub-stations .

33. The pasteurising system according to claim 32, characterised in that each of the sub-stations can house a number of foodstuffs (2) substantially corresponding to that which can be housed in the pasteurising chamber (3) .

34. The pasteurising system according to any of the foregoing claims, characterised in that the electronic control system is programmed to supply steam in the pasteurising chamber (3), using the supply means, creating an average temperature of between 100⁰C and HO⁰C inside it.

35. The pasteurising system according to any of the foregoing claims, characterised in that the electronic control system is programmed to supply steam in the pasteurising chamber (3), using the supply means, creating less than 0.46 bar inside it.