Apparatus and method for pasteurizing eggs at low temperature

Abstract

The apparatus (11) for pasteurizing eggs comprises a feeding device (2) for receiving and transferring eggs (11) to a carrier (10), a chamber (3) for heating and pasteurizing the eggs (11), a conveyor device for moving the carrier (10) with the eggs (11) through the chamber (3), a transfer station for transferring the eggs (11) from the carrier (10) to a transport device (21, 22) and a packing station (7) for packaging the coated eggs (11), and is provided with a spraying device (15) by which the eggs (11) in the chamber (3) are sprayed with a liquid.Furthermore, the present invention relates to a method for pasteurizing eggs.

Description

[Technical field]

[0001] The present invention relates to an apparatus for pasteurizing eggs, the apparatus comprising a feeder for receiving eggs and transferring them to a carrier, a chamber for heating and pasteurizing the eggs, a conveyor for moving the carrier with the eggs through the chamber, a transfer station for transferring the eggs from the carrier to a transport device, and a packing station for packaging the coated eggs.

[0002] The present invention further relates to a method of pasteurization, including the steps of feeding eggs to a feeding device that receives the eggs and transfers them to a carrier, moving the carrier with the eggs through a chamber and heating the eggs for pasteurization, transferring the eggs from the carrier to a transport device, coating the eggs in a coating device, and packaging the coated eggs. [Background technology]

[0003] US Patent Publication 2011 / 0300023 discloses an apparatus and method for pasteurizing eggs, in which eggs are loaded into carriers in layers. These carriers with the stacked eggs are placed in a hot water bath in a cold state, and then the eggs are passed through a bath that heats them to a predetermined temperature, thereby killing the Salmonella bacteria in the eggs.

[0004] After the carriers are drawn through the bath, they are removed with the eggs for further processing, e.g., coating and packaging. Disadvantages of this process are the relatively high energy required to heat and circulate the water bath and the complicated temperature control in the water bath. In addition, because the eggs are tightly positioned in the carriers, the yolks can migrate upwards during pasteurization, adversely affecting the appearance of the cooked eggs. Summary of the Invention [Problem to be solved by the invention]

[0005] The object of the present invention is therefore to create an apparatus and a method for pasteurizing eggs at low temperatures, which is able to operate with a low energy input and which avoids the above mentioned drawbacks. [Means for solving the problem]

[0006] This problem is solved by a device having the features of claim 1 and by a method having the features of claim 9.

[0007] In the device according to the invention, a spraying device for heating and pasteurizing the eggs is provided in the chamber, which can spray a liquid onto the eggs in the chamber, so that the eggs no longer have to be passed through a water bath via a carrier, but can be pasteurized via the sprayed heated or warmed liquid, in particular water.

[0008] The sprayed liquid can be easily adjusted in temperature, reducing the amount of control required to set the temperature inside the chamber. The chamber can be divided into different areas to first heat and then pasteurize the eggs, whereby the temperature and / or amount of sprayed liquid is constant or different. This process is also effective and can be carried out with low energy consumption, especially if the walls around the chamber are properly insulated.

[0009] The eggs are preferably rotated at least in sections via the carrier during their movement through the chamber, for which purpose the carrier is guided in a serpentine manner through the conveyor device, so that the eggs can rotate together with the carrier at least in the bends of the conveyor device. The carrier can be moved up and down along the vertical portions so that, for example, a spraying device can be positioned between the two vertical portions for a compact configuration so that liquid can be sprayed on both sides to wet the carrier and the eggs placed within the carrier.

[0010] Each carrier is preferably channel-shaped with multiple egg receptacles. Each receptacle is configured as an opening to allow the eggs to be wetted with liquid from different sides. The channel-shaped configuration of the carriers allows the eggs to initially rest on one leg of the carrier as they pass through the chamber and then rotate from this leg onto the other leg as the carrier passes through the bend in the serpentine guideway. This rotational movement of the eggs during pasteurization prevents the yolk from migrating upwards during pasteurization, so that the yolk remains in the center of the egg after pasteurization.

[0011] For efficient use of the liquid, it is desirable to circulate the liquid through a pump so that the liquid ejected and collected from the chamber can be fed back to the ejector via the pump, which also reduces the energy required to heat the liquid.

[0012] An inspection station with a scanner is preferably provided behind the chamber, by means of which cracks in the surface structure of the eggs can be detected, which facilitates the sorting of defective eggs. The inspection station is preferably arranged upstream of a coating station for coating the eggs, so that smaller remaining cracks can be sealed via the coating station. Means for cooling the coated eggs are preferably provided behind the coating station in order to preserve them as long as possible.

[0013] In the process according to the invention, the eggs are picked up at a feed station and preferably transferred to a carrier at a transfer point via a roller conveyor. The carrier with the eggs then moves through a room, in particular in a serpentine manner, for heating and pasteurizing the eggs. The eggs are then transferred from the carrier to a transport device for optional coating and packaging. For heating and pasteurization, eggs are sprayed with a liquid and exposed to predetermined temperatures, for example 55° C. and 65° C., to kill the Salmonella bacteria by heating the eggs. This process can be carried out in a particularly energy-efficient manner by spraying with a liquid, particularly warm water.

[0014] During its passage through the chamber the egg is preferably rotated over at least a portion of its path so that the yolk remains in the centre of the egg. To this end the egg is moved along a serpentine path via a carrier whereby the egg is rotated at least around the bends in the serpentine path. Egg carriers can be moved around the room on a conveyor system, so there is no need to heat them every time a new egg is removed.

[0015] The carriers can pick up the eggs to be pasteurized at the entrance of the room and then discharge the pasteurized eggs at the exit of the room, which can be more energy efficient and maintain a constant temperature level in the room if the carriers are circulated within the room and do not leave the room.

[0016] The residence time of the eggs in the room is preferably between 20 and 60 minutes, depending on how high the log level needs to be to reduce the Salmonella load, with a residence time of 30 to 50 minutes in the room proving to be particularly advantageous.

[0017] The liquid used to spray the eggs is preferably collected in a collection basin within the chamber and circulated in a circulation process. The collected liquid is then purified using filters and optionally a UV station where the liquid is sterilized using UV light. This makes it easy to bring the liquid up to the desired temperature.

[0018] An inspection station for detecting cracks in the surface structure is provided behind the chamber, whereby the eggs are preferably scanned and rotated on the transport device during scanning so that defective eggs can be easily sorted out.

[0019] The pasteurization device also makes it possible to transport the eggs in a continuous process so that each egg can be accurately tracked. The conveying and transport device is preferably configured so that the eggs are guided without contact with other eggs and each egg is assigned to a predefined location by a control system, so that it is possible to identify which batch of eggs is arranged in a predefined package. [Brief description of the drawings]

[0020] The invention is explained in more detail below with reference to the accompanying drawings. [Figure 1A] FIG. 1 is a side view of an egg pasteurization apparatus according to the present invention; [Figure 1B] FIG. 2 is a top view of the device shown in FIG. [Diagram 2] FIG. 1 is a schematic diagram of a chamber conveyor. [Diagram 3] FIG. 13 is a detailed view of eggs at the coating station. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0021] 1A and 1B show an apparatus for pasteurizing eggs, which initially has a loading station 1, to which the eggs are fed via a carrier. The eggs are then transferred from the loading station 1 to a feeding device 2, which removes the eggs from the carrier, for example via a suction device. The eggs are then transported and separated via a roller conveyor 25, each egg being placed on two rollers which are moved in the transport direction and which rotate the eggs so that their longitudinal axis is aligned parallel to the longitudinal axis of the rollers. This roller conveyor 25 can then transfer the eggs at a transfer point 26 to a carrier, which guides the eggs through a chamber 3 for heating and pasteurization.

[0022] From room 3, the pasteurized eggs are transferred from a carrier to a transport device and passed to inspection station 4 where any cracks in the surface structure can be detected and defective eggs can be sorted out. After inspection station 4, the eggs are fed to coating station 5 before being cooled in cooling station 6.

[0023] Figure 2 shows the chamber 3 for pasteurisation. The eggs to be pasteurised come from a roller conveyor 25, which carries several parallel tracks of eggs to the chamber 3. Each egg is located between two rollers which rotate and move towards the chamber 3 so that the row of eggs can be transferred to the carrier 10 at the transfer point 26, where the eggs are guided in circulation on a conveyor device in the chamber 3.

[0024] The carrier 10 may be constructed as disclosed in EP 3 087 017, which is incorporated herein by reference. The carrier 10 is channel-like and has a number of receptacles in the form of openings into which an egg is inserted. Depending on the length of the carrier, for example, 5-30 eggs, in particular 8-18 eggs, may be inserted into one carrier.

[0025] A part of the conveyor system in the room 3 is shown diagrammatically in the central region of Figure 2. The carriers 10 are channel-shaped, U-shaped in cross section and comprise a rear leg 12 and a front leg 13 in the conveying direction. In Figure 2 only one egg 11 is shown on the carrier 10, whereas multiple eggs 11 are arranged one behind the other in the longitudinal direction of the carrier 10, and furthermore every carrier can be filled with one or more eggs 11.

[0026] The carrier 10 is guided in a serpentine manner on the conveyor system, moving up and down between the vertical sections. Between the two vertical sections there is a deflection, which is shown diagrammatically by a curved arrow. It can be seen that the deflection causes the carrier 10 to rotate approximately 180°, with the rear leg 12 being initially at the bottom and then at the top after the deflection.

[0027] Due to the rotational movement of the carrier 10 in the region of the bend, the egg 11 placed in the carrier 10 also rotates, so that the upward floating of the egg yolk is prevented by the stationary alignment and long residence time in the chamber 3. The carrier 10 and the egg 11 are rotating in opposite directions at the bend. The rotation of the carrier 10 and the egg 11 occurs at both the upper and lower bend points.

[0028] The eggs 11 are heated to a predetermined temperature, for example between 55°C and 65°C, for pasteurization, whereby the eggs 11 are sprayed with a liquid, in particular hot water, for this purpose. Optionally, additives can also be added to the hot water. A spraying device 15 with a number of nozzles is arranged adjacent to the carrier 10, which sprays a warm or hot liquid onto the eggs 11 arranged in the carrier 10. The spraying device 15 is equipped with nozzles, which are arranged between two vertical parts of the conveyor device, so that the nozzles can spray the warm or hot liquid on both sides. The spraying device 15 with nozzles is supplied via a line 14.

[0029] Figure 2 shows only a small section of the conveyor system passing through the chamber 3. The carriers 10 are circulated in the chamber 3 and therefore do not reach an environment requiring reheating. The eggs 11 taken over by the feeder 2 are first preheated in the chamber 3, for example by air and mist. After a preheating time, the eggs 11 in the carriers 10 are sprayed with a liquid, preferably at a temperature between 58°C and 62°C. The sprayed water is then added to the carriers 10.

[0030] The sprayed water is then collected in a sediment basin and directed to drainage. From there, the collected water is transferred via a pump to a line connected to line 14, whereby hot water is sprayed again onto the eggs 11. Upstream or downstream of the pump, there can be provided a device for cleaning the liquid, in particular a filter and a UV cleaning station where the liquid is irradiated with UV light in order to sterilize it. The purified liquid can then be circulated.

[0031] After the eggs 11 have been in the chamber 3 for between 30 and 60 minutes, in particular between 40 and 50 minutes, they are transferred from the carriers 10 to a transport device 21. The transport device 21 can be configured as a roller conveyor on which the eggs rest on two roller bars which move in the transport direction and also rotate.

[0032] The transport device 21 guides the eggs 11 through an inspection station 4, which may include a scanner, whereby the eggs 11 are rotated during scanning via the transport device 21 to detect any cracks in the surface structure. In this way, defective eggs can be easily sorted out after the inspection station 4, optionally via an automatic removal device. Additionally or alternatively, a manual quality control of the surface structure of the eggs 11 can also be performed.

[0033] Behind the inspection station 4, the eggs 11 are transported to the coating station 5 via a transport device 21, which is shown in detail in figure 3. Each egg 11 sits on two adjacent supports 22, which are curved and adapted to the outer contour of the egg 11. Each support 22 is arranged on a rotating rod 27, which moves in the transport direction, such that the eggs 11 rotate also during the transport movement.

[0034] One or more spray nozzles 23 are positioned around the eggs 11, which spray coating liquid 24 onto the eggs 11. Optionally, the transport device support 22 is star-shaped in cross section and has multiple outwardly projecting projections so that there is only a small contact surface between the eggs and the support 22. Thus, the eggs 11 can be coated in a continuous process, whereby shellac, wax, or another food-approved coating material can be used for the coating.

[0035] The coated eggs are now fed to the cooling station 6 shown in Figures 1A and 1B via a transport device which transfers the eggs to individual transport elements which, at least in certain areas, move through the cooling chamber in a serpentine manner. The transport elements are guided around the periphery of the cooling station 6 in order to minimize the heat transfer from the outside to the cooling chamber.

[0036] Downstream of the cooling station 6 is a packaging station 7 where the coated and cooled eggs can be transferred into the desired packaging container, in particular egg cartons. The egg cartons can thus be labelled, thereby making it possible to separate the eggs at the start of the process and still keep track of which eggs they are, i.e. which batch they come from. [Explanation of symbols]

[0037] Reference Code List 1 Loading Station 2 Feeding device 3 rooms 4. Inspection Station 5. Coating Station 6. Cooling Station 7 Packaging Station 10. Career 11 Eggs 12 Legs 13 Legs 14 Line 15 Spraying device 21 Transport equipment 22 Transport equipment 23 Spray nozzle 24 Coating Liquid 25 Roller Conveyor 26 Transfer Point 27 Rod

Claims

1. An apparatus for pasteurizing eggs (11), comprising: a) a feeding device (2) for receiving and transferring eggs (11) to a carrier (10); b) a chamber (3) for heating and pasteurizing eggs (11); c) a conveyor system for moving the carriers (10) with the eggs (11) through the chamber (3); d) a transfer station for transferring eggs (11) from the carrier (10) to the transport device (21, 22); e) a packing station (7) for packing the coated eggs (11); The apparatus is characterized in that it is provided with a spraying device (15) by which the eggs (11) in the chamber (3) are sprayed with a liquid.

2. 2. The device according to claim 1, wherein the eggs (11) are rotatable at least in part via the carrier (10) during their movement through the chamber (3).

3. 3. The device according to claim 1 or 2, wherein the carrier (10) is guided in a serpentine manner on a conveyor device, and the eggs (11) are rotatable together with the carrier (10) at at least one bend in the conveyor device.

4. 4. The device according to claim 3, wherein the carrier (10) is movable up and down along vertical sections, and the spraying device (15) is arranged between two vertical sections.

5. 3. Device according to claim 1 or 2, wherein each carrier (10) is in the form of a channel with a plurality of receptacles for the eggs (11).

6. 3. Apparatus according to claim 1 or 2, wherein a pump (19) is provided to return the liquid recovered from the chamber (3) to the spray device (15).

7. 3. An apparatus according to claim 1 or 2, wherein an inspection station (4) equipped with a scanner is provided, by means of which cracks in the surface structure of the eggs (11) can be detected.

8. 3. The device according to claim 1 or 2, further comprising a coating station (5) for coating the eggs (11) and a cooling station (6) for cooling the coated eggs (11).

9. A method for pasteurizing eggs (11), comprising: feeding the eggs (11) to a feeding station (2) that receives the eggs (11) and transfers the eggs (11) to a carrier (10); moving the carrier (10) with the eggs (11) through the chamber (3) and heating the eggs (11) for pasteurization; transferring eggs (11) from the carrier (10) to a transport device (21, 22); Packing eggs (11), 1. A method characterized in that eggs (11) are sprayed in a chamber (3) with a liquid for heating and pasteurization.

10. 10. The method of claim 9, wherein the eggs (11) rotate over at least part of their path as they pass through the chamber (3).

11. 11. A method according to claim 9 or 10, wherein the eggs (11) move on the carrier (10) along a serpentine path, the eggs (11) rotating at the bends of the serpentine path.

12. 11. The method according to claim 9 or 10, wherein the residence time of the eggs (11) in the chamber (3) is between 20 and 60 minutes.

13. 11. The method according to claim 9 or 10, wherein the liquid sprayed onto the eggs is collected and circulated in a circulation step.

14. 14. The method according to claim 13, wherein the circulating liquid is purified through a filter (17) and a UV station (18).

15. 11. The method according to claim 9 or 10, wherein the eggs (11) are scanned in an inspection station (4) for detecting cracks in the surface structure, the eggs (11) being rotated via a conveying device (21, 22) during scanning.

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