US20180282044A1

US20180282044A1 - Packaging system, container therefor and process for packaging a product

Info

Publication number: US20180282044A1
Application number: US15/766,529
Authority: US
Inventors: Craig HARDWICK; Alan Davey
Original assignee: Linpac Packaging Ltd
Current assignee: Linpac Packaging Ltd
Priority date: 2015-10-07
Filing date: 2016-07-28
Publication date: 2018-10-04
Also published as: CA3001276A1; WO2017060668A1; EP3359466A1; GB201517741D0; AU2016333733A1; GB2543074A

Abstract

A process for packaging a product, such as a food product, including a step of creating a vacuum reservoir. Also, a packaging system comprising a vacuum reservoir

Description

The present invention relates to containers suitable for use in the packaging, storage, transportation and/or display of a product, such as a fresh food product, and to processes for making such containers. More particularly, the present invention relates to containers for the vacuum skin packaging of products and corresponding processes.
It is known to use plastic containers to package, store, transport and display fresh food. These containers may be sealed with a lidding film to protect the food within the container from the surrounding environment. Additionally, the atmosphere within such containers may be modified to enhance the shelf life and/or appearance of the fresh food within the container.
Alternatively, the products can be packaged by way of known vacuum packaging processes. For example, vacuum skin packaging processes are widely used for packaging fresh products such as meat, poultry, fish, cheese and the like. The product is typically placed on a support; a film is positioned above the product and heated; the air between the product and the film is evacuated and vacuum is applied so that the film contacts the product and the support thereby forming a tight “skin” around the product and a seal with the support. Vacuum skin packaging usually increases the shelf life of fresh products.
It has also been observed, both in conventional containers and in vacuum packaging, that juices exuded by products, such as blood from meat, remain in contact with the product and, as well as being unsightly, affect its quality and freshness. Absorbent pads can be inserted and although the exudates are absorbed, they remain in contact with the product. Other packaging designs have been developed wherein the exudates is isolated from the products (for example in EP 2 540 642 and U.S. Pat. No. 7,921,992) but these packaging often have intricate designs, which complicate the manufacturing processes and increase the associated costs. In a similar way, the ongoing aging of a natural product such as meat, can generate some gaseous products which progressively degrade the vacuum between product and skin film, and thus reduce its effectiveness.
It is an object of the invention to at least alleviate the above-mentioned disadvantages, or to provide an alternative to existing products.
According to a first aspect of the invention, there is provided a process for packaging a product comprising the step of creating a vacuum reservoir in a container. The vacuum reservoir can take up the liquids exuded from the product as well as any gases arising from the aging of the product to maintain a desired level of vacuum within the pack. This can increase the shelf life of fresh products when compared to conventional vacuum packaging systems as well as improve organoleptics and eating quality.
In a preferred embodiment, the process comprises the steps of positioning a support for the product into a container so as to create a reservoir beneath the support; placing the product(s) onto the support; placing a thermoplastic film over the product(s) the container; and removing the air between the container, the product(s), and the film.
Preferably, the process further comprises the step of lifting and heating the film above the container. For example, the film is drawn upwards by vacuum to form a dome shape above the container and heated to soften the material of the film.
Preferably, the process comprises the step of applying vacuum so that the film contacts the product and the support.
Preferably, the process comprises the step of applying vacuum so as to create a vacuum reservoir between the support and the container. The air is removed from the container and the film is sucked downwards onto and around the product and onto the upper surface of the support.
Preferably, the container comprises a base and one or more side walls extending from the base. This feature is particularly advantageous in that the container provides rigidity and protection to the packaged product. In addition, it facilitates the packaging, handling, transport and display of the packaged product. The base of the container may be substantially rectangular, square, or circular or any shape suitable for the intended use.
The packaging system according to the present invention may be a two-part system comprising a container and a support, which are detachably coupled. The support can be inserted and positioned into the container so as to create a space between the base of the container and the lower surface of the support, for a vacuum reservoir. Within the context of the invention, a packaging system in which the container and the support are not detachable and/or integrally formed is also considered.
In a preferred embodiment, the container comprises means for positioning the support within the container. This allows the support to be positioned so as to create a vacuum chamber of suitable dimensions and shape. By controlling the position of the support, the volume and therefore the vacuum capacity of the vacuum reservoir can be adjusted according to the intended use.
Preferably, the container comprises one or more positioning recesses in one or more side walls. For example, the outer edge of the support can be inserted or slotted into one or more recesses so as to be retained in the correct position. Preferably, the container comprises one or more positioning ribs in one or more side walls. More preferably, the support can be slotted and/or retained between two or more ribs. Preferably, the container comprises a positioning platform to support the support above the base of the container. The platform may run along the whole or part of the inner periphery of the side walls. It may be one or more platforms. Preferably, the base of the container comprises one or more positioning ribs. Preferably, the highest portions of the ribs are aligned within a same plane. The highest portion of the ribs preferably comprises a substantially flat surface. Preferably, the ribs extend from the side wall(s) of the container. In addition or alternatively, ribs and/or platforms are located in one or more corners of the container.
Preferably the process comprises the step of applying adhesive onto the positioning means of the container, prior to positioning the support onto the positioning means. The adhesive may be applied by means of one or more rollers, nozzles and/or any other suitable technique, to apply a homogenous layer of adhesive, or more preferably using a robot, such as an automated robot, programmed to apply one or more beads of adhesive, which will be flattened by the support in position. In some applications, the use of adhesive is not required. Clipping features can also be employed in the design of the sidewalls of the container as an additional or alternative way of securing the support.
In a preferred embodiment, the container is nestable and/or stackable with other containers of the same type. The container may comprise one or more features to facilitate the separation of nested or stacked containers, for example denesting recesses. The packaging system of the present invention is therefore easy to store and transport, as the containers can be nested or stacked onto each other. The supports can be provided separately and the system assembled at the point of packaging, or the containers can be manufactured with integral supports and shipped in that format to their point of use.
Preferably, the container comprises or consists of a rigid or semi-rigid sheet, suitably formed into the useful container shape. Preferably, the container comprises or consists of one or more commonly thermo-formed thermoplastic materials such as polyethylene terephthalate (PET), recycled polyethylene terephthalate (rPET), polypropylene (PP), polyethylene (PE), polystyrene (PS), expanded polystyrene (EPS), each of which can have various advantages in terms of recyclability, recycled content, rigidity, gas barrier properties, visual appearance and the like. Other preferred materials include Polyethylene peelable (PEP), PET/PE, PET/PEP, rPET/PE and rPET/PEP layers. Containers comprising PET/PEP or rPET/PEP layers are preferred in peelable applications, whereas PET/PE or rPET/PE layers are preferred for lock-sealed but non-peelable applications.
Preferably the container and/or the support comprise of a polyethylene surface layer (or liner) to improve the sealing characteristics of the skin film to the tray and provide a seal that can be easily peeled during opening.. preferred material for the container is PET, which provides an efficient barrier to gas and prevents the loss of vacuum. Thus, the container may comprise or consist of PET.
Preferably the liner (food contact side) has good sealing properties and for example comprises or consists of PE or a modified PE material with peelable properties brought about by techniques known in the art.
Preferably, the skin film comprises material combinations known in the art that give good skinning performance including but not limited to puncture resistance, high gas barrier, good conformability to complex product shapes, good sealing properties with lock-seal and peelable tray substrates. In addition, the skin film preferably comprises a gas barrier layer (for example oxygen and/or carbon dioxide barrier) to prevent loss of the vacuum.
The support may be a substantially flat insert. The outer perimeter of the support may have substantially the same shape as the inner perimeter of the container. The outer perimeter may have slightly smaller dimensions than the same dimensions as those of an inner perimeter of the container. The outer perimeter of the support may be such that there is one or more gaps between the outer perimeter of the support and the inner periphery of the container to allow for the passage of gas and/or fluids. The support may have angular or curved corners. The support may be clipped, slotted, placed, glued or otherwise fitted into position.
Alternatively the substantially flat insert may itself be thermoformed so as to confer additional features, such as aids to efficient stacking, strengthening ribs, or lugs to prevent inadvertent movement of the product to be packaged.
Preferably, the support comprises one or more apertures and/or perforations. More preferably, the support comprises perforations arranged in a pattern, for example so that the perforation locations correspond to recesses in the base of the tray. The perforations may be aligned which each other or staggered. In addition or alternatively, the support may comprise one or more slits. For example, the slits may be parallel to the longitudinal walls or the lateral walls of a substantially rectangular container. The apertures, perforations and/or slits are such that they allow for the passage of gas and/or fluids. The apertures are a useful feature for adjusting the performance of the whole package of this invention, and can he used to adjust the rate and amount of the passage of exudates or gases between the packed product and the vacuum reservoir.
According to a second aspect of the invention, there is provided a packaging system for use in the process as described above, wherein the system comprising a vacuum reservoir.
According to a third aspect of the invention, there is provided a container for use in a packaging system according to the present invention and as defined in any one of the preceding paragraphs.

The invention will be further described with reference to the drawings and figures, in which

FIGS. 1 and 2 are schematic perspective representations of a first packaging system according to the present invention, wherein the container and the support are shown prior to assembly;

FIG. 3 is a schematic perspective representation of the packaging system of FIGS. 1 and 2, wherein the container and the support are shown in an assembled configuration;

FIG. 4 is a schematic top representation of the packaging system of FIG. 3; FIGS. 5A and 5B are cross-sectional views of the packaging system of FIG. 3;

FIGS. 6 and 7 are schematic perspective representations of a second packaging system according to the present invention, wherein the container and the support are shown prior to assembly;

FIG. 8 is a schematic perspective representation of the packaging system of FIGS. 6 and 7, wherein the container and the support are shown in an assembled configuration;

FIG. 9 is a schematic top representation of the packaging system of FIG. 8, shown without its support;

FIGS. 10A and 10B are side and front representations of the packaging system of FIG. 8;

FIG. 11 is a schematic representation of a support comprising a series of slits for use in a packaging system according to the present invention;

FIG. 12 is a schematic perspective representation of a third packaging system according to the present invention, wherein the container and the support are shown prior to assembly;

FIG. 13 is a schematic perspective representation of the packaging system of FIG. 1:2, wherein the container and the support are shown in an assembled configuration;

FIG. 14 is a schematic top representation of the packaging system of FIGS. 12 and 13, shown without its support; and

FIGS. 15A and 15B are side and front representations of the packaging system of FIGS. 12 and 13.

Referring to FIG. 1, there is illustrated a packaging system 1 comprising a container 2 and a support 3. A vacuum reservoir 4 is illustrated on FIGS. 5A and 5B.
The container 2 comprises a base 5 and side walls 6 extending from the base 5. The container 2 can be manufactured by thereto-forming or injection moulding processes as known in the art. An advantage of the present invention is that the elements of the packaging system 1 are simple to manufacture and little modification to existing manufacturing tools is required. Furthermore, the tray described herein can be utilised on typical industrial vacuum skinning equipment in exactly the same way as trays of the prior art and yet confers the benefits of extended shelf life and improved organoleptic and eating qualities without any adaptations to the machinery.
The container 2 consists of or comprises one or more materials and/or layers selected from PET, rPET, PP, PE, PS, EPS, PET/PE, PET/PEP, rPET/PE and rPET/PEP.
One or more, in this case several, ribs 7 formed in the base 5 of the container 2. These ribs 7 have a substantially flat upper surface and form a supporting and positioning platform for the support 3. One or more ribs 8 are formed in the side walls 6 of the container 2. The ribs 8 have a slopped upper surface (relative to the side wall) to facilitate the insertion of the support 3 and a lower surface which is substantially perpendicular to the side wall 6 so as to prevent the support 3 from dislodging itself. Thus, the support 3 is retained between the base ribs 7 and the wall ribs 8. Other configurations may be envisaged. For example, the side walls 6 may comprise recesses, such as recesses formed by two ribs, between which the support 3 can be inserted.
In this embodiment, the container 2 is nestable with other containers of the same type and comprises recesses 9 located adjacent or at one more corners so as to facilitate the separation of nested containers. The container 2. comprises a peripheral flange 10 surrounding the mouth of the container 2 to facilitate handling, packaging, nesting and/or stacking.
The support 3 consists of a substantially flat insert with an upper surface 3 a for supporting a product (not shown) and a lower surface 3b. In the assembled configuration shown in FIGS. 3 to 5, the vacuum reservoir 4 is defined by the lower surface 3b of the support 3, the base 5 and side walls 6 of the container 2. The support 3 comprises a semi-rigid or rigid material. The support 3 comprises or consists of a rigid or semi-rigid flat sheet or a thermo-formed shaped platform comprising or consisting of a thereto-plastic material such as PET, recycled PET, PP, PS, PE. The simple structure of the support 3 is particularly advantageous for manufacture, transport and handling purposes. Although substantially flat, the insert can itself be thermo-formed with features to define product placement area or to increase stiffness of the insert
In the preferred embodiment, the support comprises one or more apertures, more preferably a series of perforations 15. For example, the support may be formed from a sheet comprising from 2,000 to 2,500 perforations per square meter, which is then cut into supports of for example 220 mm by 137 mm each comprising 60 to 70 holes. The perforations 15 facilitate both the generation of the vacuum reservoir and the flow of blood and meat juices from the product into the vacuum reservoir. Flow of gas and meat juices can be controlled and adapted by changing the pattern, frequency and size of the perforations.
Preferably, each perforation 15 has a diameter of 1 mm to 1.5 mm. Within this diameter range, the perforations 15 are large enough for liquids to seep through, but small enough so that the meat product is not bowing into the apertures thereby blocking fluid passage. However, it has been observed that diameters of 2 mm or more leads to some extrusion of meat through the holes. Preferably, the perforations 15 are located at around 25 mm from each other.
In another embodiment, the container 2 and the support 3 are integrally formed. Alternatively, in use, the support 3 is coupled to the container 2 is a non-detachable manner. In another embodiment, the support 3 is partly connected to the container 2. For example, the support 3 may be hingedly connected to the container 2.
FIGS. 6 to 10 illustrate a second packaging system according to the present invention. The system 1 comprises a support 3 with an upper surface 3 a and a lower surface 3 b, a container 2, and a vacuum reservoir 4. The container 1 comprises a base 5 and side walls 6. The differences between the containers of the first and second packaging system are discussed below.
The container 1 comprises positioning ribs 11 formed in the base 5 of the container 1 and extending from the side walls 6 of the container 1. In addition, the container 1 comprises a positioning platform 12 located at each corner of the container 1. In this embodiment, the positioning ribs 11 and the platforms 12 comprise a substantially flat upper surface for placing the support 3 thereon. The upper surfaces are located within a same place to receive the substantially flat support 3. The support 3 is therefore positioned above but not against the base 5, so as to create a vacuum reservoir 4 between the lower surface 3 a of the support 3 and the base 5.
The base 5 of the container 1 comprises absorption features 13 comprises a plurality of recesses and protusions; recesses to receive any fluid seeping from the product and protrusions to direct the fluid towards the recesses, and to support the platform so as to resist the collapsing influence of the vacuum in the reservoir. With reference to FIG. 11, the fluid can seep from the product, through slits 1.4, into the vacuum reservoir 4. Where the support 3 comprises apertures and/or perforations (not shown), the fluid can seep through said apertures and/or perforations.
FIGS. 12 to 15 illustrate a third packaging system according to the present invention. The system 1 comprises a support 3 with an upper surface 3 a and a lower surface 3 b, a container 2, and a vacuum reservoir 4. The container 1 comprises a base 5 and side walls 6. The support 3 comprises a plurality of perforations 15.
In use, a container 2 is formed by a thereto-forming process from a plastics material. The packaging system is assembled by inserting a support 3 into the container 2. Pressure is applied to push the support 2 along the sloped surface of the ribs 8, until the support 2 slots itself between the lower surface of the wall ribs 8 and the upper surface of the base ribs 7.
A layer of adhesive is applied onto the flat upper surfaces of the positioning ribs 11 and platforms 12 formed in the base 5 of the container 1, prior to positioning the support 3. The adhesive can be applied using an automated robot programmed to drop a bead of adhesive onto the upper surfaces. The use of the adhesive is not always required, as the vacuum combined with the weight of the product also maintain the support 3 into position.
Where the container 1 comprises a positioning platform (not shown) along the inner periphery of the side walls 6, then the support 3 can be placed directly onto the platform or adhesive can be applied onto the platform prior to placing the support 3.
The product is placed on the upper surface of the support 3 and a film (not shown) is placed over the container 2 containing the product and the support 3. The film consists of or comprises a plastics material such as those typically used in other skin packaging applications, for example multi-layer combinations of PE, an ethylene copolymer such as Surlyn® (Dupont Ionomer), and one or more gas barrier materials such as EVOH and/or PA.
In a preferred embodiment, the film comprises an outer layer of cross-linked material. This crosslinking process transforms the normally thermo-plastic layers to materials which are semi-thermosetting in nature. This allows, as one particular benefit, that the outer layer (for example comprising polyethylene) can be in contact with the heating dome of the vacuum skinning apparatus, which may be at up to 240° C., without melting or sticking to that dome as an untreated polymer material normally would.
The film can comprise a moisture-barrier layer or material to prevent moisture loss from the product, in particular meat products. The film can comprise an oxygen-permeable layer or material to prevent the product, in particular meat products, from drying out and to preserve its red colour.
The film is lifted above the container 2, for example by being drawn upwards by applying a vacuum, to form a dome shape above the container 2. The film is heated at temperatures ranging from 160° C. to 240° C., which are high enough so that the film material softens. The film is then sucked downwards towards the product and the support, preferably by application of vacuum. Enough vacuum is applied so that (1) the film contacts and partially surrounds the product, (2) the film contacts and adheres to the upper surface 3 a of the support 3 and to the container 2, (3) the air in the vacuum chamber 4 is evacuated, thereby creating a vacuum reservoir. The evacuation of air can be through the apertures, perforations and/or slits 14 formed in the support 3, and/or through any gap between the support 3 and the side walls 6. The product is vacuum skin packaged in a packaging system 1 comprising a container 2.
Products can be packaged in the packaging system according to the present invention through vacuum skinning processes known in the art and little or no modification of packaging machinery is required. What distinguishes the present invention is the vacuum reservoir positioned below the support and its interconnection with the food product placed on the support.
It has been observed that the shelf life of a product thus packaged is increased up to at least six weeks due to the presence of the vacuum reservoir 4 compared to 1 to 2 weeks for a product packaged in a conventional film-lidded container and 3 to 4 for a product in a conventional vacuum skin packaging without a vacuum reservoir. In addition, any exudate from the product is drawn into the vacuum chamber 4, which further decreases the risk of product degradation and produces a fresher, more appealing appearance.
The present packaging process and system have been found to he particularly advantageous when used for packaging minced meat(s) or products comprising minced meat(s). Due to its form, minced meat has a tendency to retain air and residual air may remain in the meat after the vacuum stage. In the present invention, this residual air is slowly drawn out of the meat, sucked towards and retained in the vacuum reservoir. Consequently, the shelf life of the mince meat can be further extended.
The present packaging process and system have been found to have unexpected advantages when used for packaging meat products, such as beef. Aged beef can be obtained by a dry-aging process or a wet-aging process. In a dry-aging process, beef is hung or placed on a rack to dry for several weeks under specific conditions. Once the meat has lost enough moisture, the dry crust is trimmed off and discarded. By this process, up to half of the original meat weight can be lost through drying and trimming. In a wet-aging process, the meat is typically aged in a vacuum sealed bag to retain its moisture. Generally, dry-aged beef is considered to have superior taste compared to wet-aged beef. Wet-aged beef obtained using the packaging system according to the present invention has been found to have dry-aging taste characteristics, without the associated weight loss.
In a process according to the present invention, it has been observed that a searing step prior to packaging improves the quality and taste of a meat product. Before placing the meat product, for example a beef joint, the meat is seared. The seared meat is placed onto the tray, then vacuum skinned packaged. After a period of a few days, the packaged meat is cooked sous vide for example at a temperature of from 40° C. to 70° C. for a period of from 3 to 7 hours. The product is then ready for transport and sale. The customer can cook the joint in a reduced amount of time. The resulting meat is of consistent high quality and improved taste. The implication is that it may be possible for a meat suppliers to use lower quality meat cuts and yet for the customer to enjoy a tasty meat product.
Thus, from the above description, it can he seen that the present invention provides a process and packaging system which increases the shelf-life and improves the eating quality of fresh products. This is achieved through the use of a vacuum chamber. The packaging system is simple to manufacture, to use and to transport and combines an extended shelf life compared to conventional vacuum skin film packaging with the presentation and protection benefits of rigid or semi-rigid containers.

Claims

1. A packaging system for vacuum skin packaging a product, wherein the packaging system comprises a container and a support arranged and configured to create a vacuum reservoir.

2. The packaging system according to claim 1, wherein the container comprises a base and one or more side walls extending from the base.

3. The packaging system according to claim 1, wherein the container comprises means for positioning the support to create a vacuum reservoir.

4. The packaging system according to claim 3, wherein the container comprises one or more recesses in one or more side walls.

5. The packaging system according to claim 3, wherein the container comprises one or more positioning ribs in or more side walls.

6. The packaging system according to clai herein the support can be retained between two or more ribs.

7. The packaging system according to claim 3, wherein the container comprises a positioning platform along one or more side walls.

8. The packaging system according to claim 3, wherein the base of the container comprises one or more positioning ribs and/or platforms.

9. The packaging system according to claim 1, wherein the container comprises or consists of one or more materials selected from PET, rPET, PP, PE, PS and EPS.

10. The packaging system according to claim 9, wherein the container comprises or consists of PEP, PET/PE, PET/PEP, rPET/PE or rPET/PEP layers.

11. The packaging system according to claim 1, wherein the container is nestable and/or stackable with other containers of the same type.

12. The packaging system ccording to claim 1, wherein the support is substantially flat.

13. The packaging system according to claim 1, wherein the support comprises one or more apertures, perforations and/or longitudinal slits.

14. The packaging system according to claim 1, wherein the system comprises a vacuum reservoir.

15. A container as defined in any claim 1.

16. A process for packaging a product comprising the step of creating a vacuum reservoir in a container.

17. The process according to claim 16, comprising the steps of:

a. positioning a support for the product into a container so as to create a reservoir;

b. placing the product onto the support;

c. placing a thermoplastic film over the container; and

d. removing the air between the container and the film.

18. The process according to claim 16, comprising the step of ing and heating the film above the container prior to the application of vacuum.

19. The process according to claim 16, comprising the step of applying vacuum so that the film contacts the product and the support.

20. The process according to any claim 16, comprising the step of applying vacuum so as to create a vacuum reservoir between the support and the container.

21. The process according to claim 16, wherein the film comprises one or more materials selected from PE, an ethylene copolymer, a gas and/or moisture barrier material.

22. The process according to claim 16, wherein the film comprises a sealing layer and/or a peelable layer.

23. (canceled)

24. (canceled)

25. (canceled)