Fresh-keeping and antifungal packaging device

Abstract

The present invention relates to a preservation and / or antifungal device for fresh fruits and / or vegetables, including tomatoes, grapes and in particular soft fruits, such as, but not limited to, blueberries, strawberries, raspberries and / or blackberries, wherein the device comprises a packaging container for the fruits or vegetables and a multi-layer laminated film generating sulfur dioxide (SO2) adapted to seal the container after the fruits or vegetables are packaged in the container. The invention also relates to a method for preserving fruits or vegetables and / or inhibiting the growth of fungi using the preservation and / or antifungal device.

Description

TECHNICAL FIELD

[0001] The present invention relates to a preservation and / or anti-fungal device for fresh fruits and / or vegetables, including tomatoes, grapes, and in particular soft fruits, such as but not limited to blueberries, strawberries, raspberries and / or blackberries, wherein the device comprises a packaging container for the fruits or vegetables and a multi-layered lamination film generating sulphur dioxide (S02) adapted to seal the container after the fruits or vegetables are packaged in the container. The present invention also relates to a method of preserving fruits or vegetables and / or inhibiting fungal growth using the preservation and / or anti-fungal device. BACKGROUND

[0002] It is estimated that up to 50% loss in total soft fruit, such as berries, sales can occur due to post-harvest damage or rotting of the berries. This is in part due to the fact that as non-climacteric fruits, berries must be picked at almost full ripeness and will not further ripen after picking.

[0003] Currently, the most common method of maintaining quality over a period of post-harvest is prompt pre-cooling and storage at low temperatures.

[0004] Soft fruits, such as berries, are often packaged in wide and shallow containers, no more than three layers of fruit, in order to prevent the fruit at the bottom from being crushed by the fruit at the top. Even more commonly, packaging in the form of flip-top or shallow boxes with lids are used to prevent moisture loss. These also provide mechanical protection for the delicate fruit, can be transparent or clear to allow the consumer to inspect the fruit as desired at the time of purchase, and are relatively inexpensive. Typically, the containers are vented on the top surface and / or sides.

[0005] However, another method for packaging soft fruits is to use film-sealable containers with or without additional lids, but preferably without additional lids. Such packaging can be plastic or paper pulp shallow boxes or trays with heat- or cold-seal film closures and are typically constructed of recyclable materials, such as polyethylene terephthalate (PET) packaging.

[0006] Typically, the source of infection that causes fresh fruits and vegetables to rot is fungi and / or bacteria. It is crucial to prevent the development of rot that pre-cooling to about 0°C is preferably done immediately after picking. Generally, a high relative humidity of about 85% to 95% is maintained in the transport containers or storage rooms, although the moisture on the actual fruits or vegetables or in the packaging should be kept to a minimum in order to reduce the level of fungal spoilage. Typically, the transport and storage temperatures are kept below 5°C, usually by forced air cooling.

[0007] Soft fruits such as strawberries, raspberries, blueberries and blackberries also have a high respiration rate and are particularly susceptible to rotting caused by pathogenic agents that cause rot (such as Botrytis cinerea which causes grey mould rot). The presence of ethylene can further stimulate respiration and promote growth of Botrytis.

[0008] SO2 generating devices are mainly used for blueberries, typically utilising small packs containing SO2 generating chemicals such as sodium metabisulphite (SMBS) at concentrations of about 8 to 15% and generated in the pack.

[0009] However, these SO2 generating packs are associated with bleaching of the berries. Furthermore, the type of pack used plays an important role in maintaining the freshness and quality of the fruit and vegetables and it has been found that heat-sealed containers such as punnets are more effective than those with lids in reducing weight loss of the product over time. It would be useful if such heat-sealed films could be adapted to contain preservative and anti-fungal agents in order to provide protection for fresh produce from farm to consumer, thereby helping to maintain the quality of fresh produce, extend its shelf life, prevent the development of rot and reduce food loss and waste.

[0010] Although laminated films generating controlled release SO2 are known, such as described by Clemes et al (US 5,106,596 and US 7,045,182), when used for soft fruits such as berries, these are found to cause significant phytotoxicity due to the sensitive nature of berries compared to grapes for which such products are typically designed. It would be useful to have a product that can be used not only for a variety of fresh produce applications from vegetables (such as tomatoes) to fruits (such as grapes) but also including problematic fruits such as soft fruits.

[0011] Furthermore, as berries are required to be picked close to maturity, it would be beneficial if additional additives such as ethylene scavengers could be included.

[0012] Therefore, there remains a need for a method or device for maintaining the quality of fruits and vegetables including tomatoes and grapes and in particular soft fruits such as berries in containers during shipping or storage and when left on display at the retailer, particularly when temperatures are elevated during shipping, transhipment or storage which in turn causes an increase in the fungal growth capacity of fungi including Botrytis sp. on the fruit or vegetable and its stem.

[0013] Furthermore, the multi-layered films currently used for the preservation of grapes such as those described by Clemes et al are not recyclable, being produced by a mixture of polymer sheets having a wax layer laminated therebetween. Given the commercial importance of providing recyclable materials nowadays, such a device should also be recyclable. SUMMARY

[0014] According to a first aspect of the present invention, there is provided a preservation and / or anti-fungal device for fruits and / or vegetables, including tomatoes, grapes, and particularly soft fruits such as berries including but not limited to blueberries, strawberries, raspberries, and / or blackberries, wherein the device comprises: a packaging container for containing the fruits and / or vegetables comprising a shallow box; and a multi-layered lamination film generating sulfur dioxide (SO2) adapted to seal the container by a sealable contact of a first operatively inwardly facing layer of the multi-layered lamination film with an open end of the container after the fruits and / or vegetables are packed in the container; wherein the SO2-generating multi-layered lamination film comprises:

[0015] (i) a first operatively inwardly facing layer which can comprise a material selected from: a thermoplastic material; a material coated with a thermoplastic coating such as a heat-seal lacquer comprising, for example, a binder containing a copolymer, an inorganic cross-linking agent, a solvent-free polyester resin, or an aqueous dispersion of a copolyester emulsion, and a filler; or a material selected from a non-thermoplastic polymer or paper without a thermoplastic coating;

[0016] (ii) a second operatively outwardly facing layer which can comprise a material selected from: a thermoplastic material; a material coated with a thermoplastic coating such as a heat-seal lacquer comprising, for example, a binder containing a copolymer, an inorganic cross-linking agent, a solvent-free polyester resin, or an aqueous dispersion of a copolyester emulsion, and a filler; or a material selected from a non-thermoplastic polymer or paper without a thermoplastic coating; and

[0017] (iii) an inner adhesive layer between the first and second layers having a coating weight of about 1 GSM to about 100 GSM or any sub-range contained therein, comprising an adhesive composition including a polyurethane adhesive composition, more preferably a solvent-free polyurethane adhesive composition, at a concentration of about 30% to about 90% weight / weight (w / w) or any sub-range contained therein; and sodium metabisulfite (SMBS) microparticles having a diameter of about 1 pm to about 250 pm or any sub-range contained therein at a concentration of about 10% to about 70% (w / w) or any sub-range contained therein,

[0018] wherein, when the first operatively inwardly facing layer comprises a material selected from a non-thermoplastic polymer or paper without a thermoplastic coating, the edge of the open end of the container or the edge of the operatively inwardly facing layer in contact with the edge of the open end of the container is coated with an adhesive including but not limited to a cold-seal adhesive, a pressure-sensitive adhesive, a peelable adhesive, and the like.

[0019] Optionally, even when the first operatively inwardly facing layer is a thermoplastic material or a material coated with a thermoplastic coating, the open end of the container may be coated with an adhesive, although this is generally not necessary.

[0020] In particular, the first operatively inwardly facing layer and / or the second operatively outwardly facing layer may comprise: paper, including kraft paper or machine glazed bleached kraft (MGBK) paper; a polyolefin film comprising biaxially oriented polypropylene (BOPP), low-density polyethylene (LDPE), high-density polyethylene (HDPE); or a polyester film comprising polyethylene terephthalate (PET). The first and second layers may be of the same or different materials.

[0021] In a preferred embodiment of the present invention, the first operatively inwardly facing layer and / or the second operatively outwardly facing layer may comprise: a polyolefin film layer in the range of about 9 μm to 150 μm or any subranges subsumed therein; or a paper layer in the range of about 13 GSM to 300 GSM or any subranges subsumed therein; or a polyester film in the range of about 3 μm to 100 μm or any subranges subsumed therein. It should be understood that the applicant has found that the above size ranges are critical for effectively controlling the water vapor transmission rate (WVTR) and oxygen transmission rate (OTR) to generate an effective amount of SO2 gas for keeping the packaged fruits and / or vegetables fresh and inhibiting fungal growth in the packaged fruits and / or vegetables during the typical time period of transportation and storage of fruits and / or vegetables through the SO2-generating multilayer laminate film.

[0022] The polyolefin film or polyester film layer of the first operatively inwardly facing layer may comprise a heat sealable material or may have an adhesive coating applied thereto. In the case of a paper layer of the first operatively inwardly facing layer, it may be coated with an adhesive coating to allow it to be sealable to the container of the device.

[0023] The container or packet may comprise a substrate comprising foil, polymer (including PET or BOPP), or a paper, pulp or card substrate (including recycled polymer or paper substrates).

[0024] The first operatively inwardly facing layer and / or the second operatively outwardly facing layer can optionally be micro-perforated, for example by heat needle perforation, cold needle perforation or laser perforation. The diameter of the perforations, the number of perforations and the arrangement of the perforations on the layer can be adjusted as desired by the user for controlling moisture and S02gas generation, for use in the preservation packaging of fruits and / or vegetables by the multi-layer S02-generating film in the range of micro-perforation diameters of about 0.05 mm to 2.8 mm or any sub-range contained therein, for fruits and / or vegetables during the typical time period of transport and storage of fruits and / or vegetables, including when on display at a retailer, and inhibiting fungal growth in the packaged fruits and / or vegetables. The spacing between the micro-perforations can optionally be 5 mm horizontally and 10 mm vertically, but it will be appreciated that the dimensions of the spacing can be adjusted as desired by the user.

[0025] In an alternative embodiment of the present application, wherein neither the first operatively inwardly facing layer nor the second operatively outwardly facing layer of the material are micro-perforated, the multi-layer S02-generating film can be micro-perforated after being laminated together, wherein the diameter of the micro-perforations ranges from about 0.05 mm to 2.8 mm or any sub-range contained therein. The spacing between the micro-perforations can optionally be 5 mm horizontally and 10 mm vertically, but it will be appreciated that the dimensions of the spacing can be adjusted as desired by the user.

[0026] Additionally optionally, the multi-layer S02-generating film can include macro-perforations for controlling air flow and moisture levels in the container, wherein the diameter of the macro-perforations ranges from about 2 mm to 100 mm or any sub-range contained therein.

[0027] It will be appreciated that the arrangement of the micro-perforations and / or macro-perforations can be such that selected regions or zones of the multi-layer S02-generating film contain micro-perforations and / or macro-perforations.

[0028] Optionally, either or both of the first operatively inwardly facing layer and the second operatively outwardly facing layer can be treated with one or more additional treatments including an anti-fog treatment, a corona treatment or a chemical treatment for ink adhesion. The first operatively inwardly facing layer and the second operatively outwardly facing layer can comprise a substantially transparent polymer.

[0029] In particular, the concentration of the solventless polyurethane adhesive composition can be about 40% to about 80% (w / w), or about 50% to about 70% (w / w) or any sub-range contained therein, and the concentration of the sodium metabisulfite (SMBS) microparticles having a diameter of about 10 pm to about 70 pm, or about 20 pm to about 50 pm or any sub-range contained therein, is about 40% to about 80% (w / w), or about 50% to about 70% (w / w) or any sub-range contained therein.

[0030] The paper may be coated on one or both surfaces with a coating (such as, but not limited to, a WVTR or OTR control coating, or any one or more of a hydrophobic coating, a hydrophilic coating, or a primer coating, as known in the art), or may be uncoated. Alternatively, the paper may be coated on one or both surfaces with a polyolefin film comprising BOPP, LDPE, or HDPE, or a polyester film comprising PET. When the paper is coated on one surface, the inner adhesive layer is applied to the coated surface of the paper.

[0031] The thickness of the first and second layers of paper (polyolefin or polyester film) are specifically selected for optimal permeability to allow water vapor from the air in the container to pass inwardly through the paper (polyolefin or polyester film) and reach the SMBS microparticles in the inner adhesive layer, thereby activating the SMBS to release SO2 gas, which in turn travels outwardly through the paper (polyolefin or polyester film) to reach the fruit or vegetables in the container at a concentration effective to reduce the level of pathogen growth or inhibit the growth of pathogens, including Botrytis cinerea in the packaged fruit or vegetables.

[0032] In particular, the first polyolefin film layer or the second polyolefin film layer may have a thickness ranging from 10 μm to 50 μm, or from 10 μm to 30 μm, or any subranges subsumed therein, and the first polyester film layer or the second polyester film layer may have a thickness ranging from 10 μm to 50 μm, or from 10 μm to 30 μm, or any subranges subsumed therein.

[0033] Furthermore, the concentration and SMBS particle diameter are specifically selected and produce effective levels of SO2 gas in the vessel of about 1 ppm to about 200 ppm for a duration of 5 days to 70 days, more typically about 20 days to about 30 days.

[0034] According to a second aspect of the present invention, there is provided a freshness-preserving and / or antifungal device for use during transport or storage (including while on hold at a retailer) of fruits and / or vegetables, including tomatoes, grapes, and in particular soft fruits, such as berries including, but not limited to, blueberries, strawberries, raspberries, and / or blackberries, wherein the device comprises: a packaging container comprising a shallow box for containing the fruits and / or vegetables; and a sulphur dioxide (SO2)-generating multilayer laminate film, the sulphur dioxide-generating multilayer laminate film being adapted to flow wrap the container with the multilayer laminate film, comprising contacting a first operatively inwardly facing layer of the multilayer laminate film with an open end of the container after the fruits and / or vegetables are packaged in the container; wherein the SO2-generating multilayer laminate film comprises:

[0035] (i) a first operatively inwardly facing layer comprising a polymer selected from the group comprising: a polyolefin film comprising biaxially oriented polypropylene (BOPP), low density polyethylene (LDPE), high density polyethylene (HDPE); or a polyester film comprising polyethylene terephthalate (PET);

[0036] (ii) a second operatively outwardly facing layer comprising a polymer selected from the group comprising: a polyolefin film comprising biaxially oriented polypropylene (BOPP), low density polyethylene (LDPE), high density polyethylene (HDPE); or a polyester film comprising polyethylene terephthalate (PET); and

[0037] (iii) an inner adhesive layer between the first and second layers having a coating weight of about 1 GSM to about 100 GSM or any sub-range contained therein, comprising an adhesive composition, including a polyurethane adhesive composition, more preferably a solventless polyurethane adhesive composition, at a concentration of about 30% to about 90% (w / w) or any sub-range contained therein; and sodium metabisulfite (SMBS) microparticles having a diameter of about 1 pm to about 250 pm or any sub-range contained therein at a concentration of about 10% to about 70% (w / w) or any sub-range contained therein.

[0038] In a preferred embodiment of this second aspect of the application, the first operatively inwardly facing layer and / or the second operatively outwardly facing layer can comprise: a polyolefin film layer ranging from about 9 pm to 150 pm or any sub-range contained therein; or a polyester film ranging from about 3 pm to 100 pm or any sub-range contained therein. It will be appreciated that the Applicant has found that the above-mentioned size ranges are critical for effective control of water vapour transmission rate (WVTR) and oxygen transmission rate (OTR) to produce an effective amount of SO2 gas by the SO2 generating multilayer film for the preservation of fruits and / or vegetables in preservation packaging and to inhibit fungal growth in the packaged fruits and / or vegetables over the typical time period of transit and storage of the fruits and / or vegetables and shelving at the retailer.

[0039] In particular, the concentration of the solventless polyurethane adhesive composition can be about 40% to about 80% (w / w), or about 50% to about 70% (w / w) or any sub-range contained therein, and the concentration of sodium metabisulfite (SMBS) microparticles having a diameter of about 10 pm to about 70 pm, or about 20 pm to about 50 pm or any sub-range contained therein is about 40% to about 80% (w / w), or about 50% to about 70% (w / w) or any sub-range contained therein.

[0040] The thickness of the first and second polyolefin or polyester film is specifically selected for optimal permeability to allow water vapor from the air in the container to pass inwardly through the polyolefin or polyester film and to the SMBS microparticles in the inner adhesive layer, thereby activating the SMBS to release SO2 gas which in turn passes outwardly through the polyolefin or polyester film to reach the fruit or vegetable in the container at a concentration effective to reduce or inhibit the level of growth of a pathogen, including Botrytis cinerea in packaged fruit or vegetable.

[0041] In particular, the first or second polyolefin film layer can range from 10 pm to 50 pm, or 10 pm to 30 pm or any sub-range contained therein, and the thickness of the first or second polyester film layer can range from 10 pm to 50 pm, or 10 pm to 30 pm or any sub-range contained therein.

[0042] Further, the concentration and SMBS particle diameter are specifically selected and result in an effective level of SO2 gas in the container of about 1 ppm to about 200 ppm for a period of 5 days to 70 days, more typically about 20 days to about 30 days.

[0043] The inner adhesive layer of any aspect of the present application can also optionally comprise a chemical ethylene scavenger selected from the group comprising potassium permanganate, zeolite, activated carbon, pumice and other chemical ethylene scavengers known in the art.

[0044] According to a third aspect of the present application, there is provided a method for manufacturing a SO2 generating multi-layered lamination film for use in the preservation and / or anti-fungal device of the present application, comprising the steps of:

[0045] (a) providing a first operatively inwardly facing layer which can comprise a material selected from the group consisting of: a thermoplastic material; a material coated with a thermoplastic coating such as a heat seal lacquer including for example a binder containing a copolymer, an inorganic cross-linking agent, a solventless polyester resin or a copolyester aqueous dispersion and a filler; or a material selected from a non-thermoplastic polymer or a paper without a thermoplastic coating;

[0046] (b) applying an adhesive layer to the first base material layer using a laminator or a coater, the adhesive layer having a coating weight of about 1 GSM to about 100 GSM or any sub-range contained therein, comprising an adhesive composition including a polyurethane adhesive composition, more preferably a solventless polyurethane adhesive composition, at a concentration of about 30% to about 90% (w / w) or any sub-range contained therein; and sodium metabisulfite (SMBS) microparticles having a diameter of about 1 pm to about 250 pm or any sub-range contained therein at a concentration of about 10% to about 70% (w / w) or any sub-range contained therein;

[0047] (c) laminating a second operatively outwardly facing layer to the adhesive layer using a laminator such that the adhesive layer is sandwiched between the first layer and the second layer, the second operatively outwardly facing layer can comprise a material selected from the group consisting of: a thermoplastic material; a material coated with a thermoplastic coating such as a heat seal lacquer, the heat seal lacquer including for example an adhesive containing a copolymer, an inorganic crosslinking agent, a solventless polyester resin or a copolyester aqueous dispersion and a filler in an aqueous emulsion; or a material selected from a non-thermoplastic polymer or a paper that does not have a thermoplastic coating; and

[0048] (d) optionally wherein, when the first operatively inwardly facing layer comprises a material selected from a non-thermoplastic polymer or a paper that does not have a thermoplastic coating, an additional step of coating the operatively inwardly facing surface of the first layer with a thermoplastic coating such as a heat seal lacquer, the heat seal lacquer including for example an adhesive containing a copolymer, an inorganic crosslinking agent, a solventless polyester resin or a copolyester aqueous dispersion and a filler in an aqueous emulsion, is performed.

[0049] The adhesive layer can also optionally comprise a chemical ethylene scavenger selected from the group comprising potassium permanganate, zeolite, activated carbon, pumice and other chemical ethylene scavengers known in the art.

[0050] In particular, the first operatively inwardly facing layer and / or the second operatively outwardly facing layer can comprise: a paper, including Kraft paper or MGBK paper; a polyolefin film comprising BOPP, LDPE, HDPE; or a polyester film comprising PET. The first layer and the second layer can have the same or different materials.

[0051] In particular, the first operatively inwardly facing paper layer and / or the second operatively outwardly facing paper layer can have a thickness in the range of about 13 GSM to about 300 GSM or any sub-range contained therein, the first operatively inwardly facing polyolefin layer and / or the second operatively outwardly facing polyolefin film layer can have a thickness in the range of 9 pm to 150 pm or any sub-range contained therein, and the first operatively inwardly facing polyester layer and / or the second operatively outwardly facing polyester film layer can have a thickness in the range of 3 pm to 100 pm or any sub-range contained therein.

[0052] The first operatively inwardly facing layer and / or the second operatively outwardly facing layer can optionally be micro-perforated, for example, by heat needle perforation, cold needle perforation, or laser perforation. The diameter of the perforations, the number of perforations, and the arrangement of the perforations on the layer are adjusted to control moisture and S02gas generation, in the typical time period for the fruit and / or vegetable to be transported and stored and to sit at the retailer, in the case of micro-perforations having a diameter in the range of about 0.05 mm to 2.8 mm, or any sub-range contained therein, for fresh-keeping packaging of fruit and / or vegetables by the S02-generating multi-layered laminate film, and to inhibit fungal growth in the packaged fruit and / or vegetables. The spacing between the micro-perforations can optionally be 5 mm horizontally and 10 mm vertically, but it should be understood that the dimensions of the spacing can be adjusted as desired by the user.

[0053] In an alternative embodiment of this third aspect of the application, wherein neither the first operatively inwardly facing layer nor the second operatively outwardly facing layer of the material are micro-perforated, the S02-generating multi-layered laminate film can be micro-perforated after being laminated together, wherein the diameter of the micro-perforations ranges from about 0.05 mm to 2.8 mm, or any sub-range contained therein. The spacing between the micro-perforations can optionally be 5 mm horizontally and 10 mm vertically, but it should be understood that the dimensions of the spacing can be adjusted as desired by the user.

[0054] Additionally optionally, the S02-generating multi-layered laminate film can include macro-perforations for controlling air flow and moisture levels in the container, wherein the diameter of the macro-perforations ranges from about 2 mm to 100 mm, or any sub-range contained therein. The spacing between the macro-perforations can optionally be 5 mm horizontally and 10 mm vertically, but it should be understood that the dimensions of the spacing can be adjusted as desired by the user.

[0055] It should be understood that the arrangement of the micro-perforations and / or macro-perforations can be such that selected areas or zones of the S02-generating multi-layered laminate film contain micro-perforations or macro-perforations.

[0056] Optionally, either or both of the first operatively inwardly facing layer and the second operatively outwardly facing layer can be further treated with one or more additional treatments including an anti-fog treatment, a corona treatment, or a chemical treatment for ink adhesion.

[0057] Prior to use in the fresh-keeping and / or anti-fungal device of the application, the S02-generating multi-layered laminate film can be cut to the desired size.

[0058] According to a fourth aspect of the present application, there is provided a method of preserving fresh fruit and / or vegetables including tomatoes, grapes and in particular soft fruit such as but not limited to blueberries, strawberries, raspberries and / or blackberries, packaged in a container or punnet during transport and / or storage, including when on display at a retailer, or inhibiting fungal growth, in particular Botrytis, in fresh fruit and / or vegetables including tomatoes, grapes and in particular soft fruit such as but not limited to blueberries, strawberries, raspberries and / or blackberries, packaged in a container or punnet, using a preservation and / or anti-fungal device according to any aspect of the present application.

[0059] According to a fifth aspect of the present application, there is provided a preservation and / or anti-fungal device according to the present application, substantially as herein described with reference to any one of the illustrative examples. BRIEF DESCRIPTION OF DRAWINGS

[0060] The present application should be described with reference to the following illustrative drawings, which should not be considered limiting of the scope of the application:

[0061] Figure 1 : shows the percentage of Botrytis growth inhibition over time (7 days) in vitro for various PET heat-seal sheets;

[0062] Figure 2 : shows the percentage of Alternaria growth inhibition over time (7 days) in vitro for various PET heat-seal sheets;

[0063] Figure 3 : shows the development of rot in 300g heat-sealed punnets of blueberries over the chilled and shelf life period;

[0064] Figure 4 : shows the development of rot in 750g heat-sealed punnets of blueberries over the chilled and shelf life period;

[0065] Figure 5 : shows the percentage of defects recorded for blackberries after 5 days of cold storage at 2°C in flow-wrap and after a further 7 days of shelf life at 15°C;

[0066] Figure 6 : shows the development of rot in blueberries over the chilled and shelf life period with the application of a heat-seal film;

[0067] Figure 7 : shows the inhibition of rot in blueberries over the chilled and shelf life period with the application of a heat-seal film;

[0068] Figure 8 : shows the development of rot in blueberries over the chilled and shelf life period with the application of a flow-wrap film;

[0069] Figure 9 : shows the inhibition of rot in blueberries over the chilled and shelf life period with the application of a flow-wrap film;

[0070] Figure 10 : shows SO2 injury of blueberries over the cold storage and shelf life period with application of heat-seal film;

[0071] Figure 11 : shows SO2 injury of blueberries over the cold storage and shelf life period with application of flow-wrapped film;

[0072] Figure 12 : shows decay inhibition of tomatoes over the cold storage and shelf life period with application of heat-seal film; and

[0073] Figure 13 : shows decay inhibition of tomatoes over the cold storage and shelf life period with application of flow-wrapped film. DETAILED DESCRIPTION

[0074] The present invention relates to a preservation and / or anti-fungal device for use during transport or storage of fresh fruits or vegetables, including when left at a retailer, including tomatoes, grapes, and in particular soft fruits such as, but not limited to, blueberries, strawberries, raspberries and / or blackberries, wherein the device comprises a packaging container for the fruits or vegetables and a multi-layer laminated film generating sulphur dioxide (SO2) adapted to seal the container after the berries are packed in the container. The present invention also relates to a method of manufacturing the device of the present invention and to a method of preserving fruits or vegetables, in particular soft fruits, and inhibiting the growth of fungal pathogens including B. cinerea with the device of the present invention.

[0075] The following description of the invention is provided as an enabling teaching of the invention and is not intended to limit the scope of the invention. Those skilled in the art will recognise that modifications and alterations of the described embodiments can be made without departing from the scope of the invention. In addition, the present invention will recognise that some benefit can be obtained from the described embodiments that do not specifically utilize all of the recited features. Accordingly, the application is not limited as described unless otherwise specifically stated.

[0076] In one illustrative embodiment of the application, the Applicant has developed a preservation and / or anti-fungal device comprising a SO2 generating multi-layered lamination film having a first operatively inwardly facing layer capable of sealable contact with the rim of the open end of a punnet after the fruit, for example berries, have been packed. In a preferred embodiment, the first layer is made of a heat sealable (thermoplastic) material or is coated with a thermoplastic coating such as a heat seal lacquer or similar coating known to those skilled in the art, such that the first layer is heat sealable to various punnet types. There are many such commercially available heat seal coatings that can be adhered to a number of types of substrates including films, foils and paper. One example includes a binder such as an aqueous emulsion containing a copolymer, an inorganic crosslinker, a solventless polyester resin or a copolyester aqueous dispersion and a filler.

[0077] The second operatively outwardly facing layer of the SO2 generating multi-layered lamination film can optionally be made of a thermoplastic material, coated with a thermoplastic coating or simply be a standard substrate material (i.e. non-thermoplastic or uncoated).

[0078] First layer

[0079] The first layer can be any of the following materials: paper including Kraft or single side light bleached Kraft (MGBK) paper; polyolefin film including BOPP, LDPE or HDPE; or polyester film including PET.

[0080] In particular:

[0081] • The polyolefin film layer can range from 9 pm to 150 pm.

[0082] • The paper layer can range from 13 GSM to 300 GSM

[0083] • The polyester film layer can range from 3 pm to 100 pm.

[0084] The polymeric film can be heat sealable or have an applied coating to make it heat sealable. The paper needs to have an applied coating to make it sealable to punnets. This makes the substrate material sealable to all available punnets (e.g. PET, BOPP or paper punnets).

[0085] The thickness and coating applied to the paper or polymeric film layer is selected to control the WVTR and OTR so as to provide an effective amount of SO2 gas for the required period of time in transit and / or storage (including when on display at a retailer).

[0086] In one embodiment of the application, the paper or polymeric film layer is micro-perforated by a perforation technique such as (hot needle perforation, cold needle perforation or laser perforation). The diameter of the perforations, the number of perforations and the arrangement of the perforations (including the possibility of having perforated and non-perforated areas on one film) are selected to control the moisture and SO2 gas release from the substrate to the fruit and / or vegetable in the package.

[0087] In particular the micro-perforation diameter can range from 0.05 mm to 2.8 mm.

[0088] Second layer

[0089] The second paper or polymeric film layer can be any of a variety of substrate materials such as: paper, including Kraft or single side light bleached Kraft (MGBK) paper; polyolefin film comprising BOPP, LDPE or HDPE; or polyester film comprising PET.

[0090] In particular:

[0091] • the polyolefin film layer can range from 9 μιη to 150 μιη

[0092] • the paper layer can range from 13 GSM to 300 GSM

[0093] • the polyester film layer can range from 3 μιη to 100 μιη.

[0094] As in the first layer, the polymeric film can be heat sealable or have a coating applied to make it heat sealable. The paper needs to have a coating applied to make it sealable to the punnet. This is desirable if you want to have a reversible product. If the product does not need to be reversible, the material used does not need to be heat sealable or coated.

[0095] The thickness and coating applied to the paper layer or polymeric film layer is selected to control the WVTR and OTR so as to provide an effective amount of SO2 gas for the required period of time in transit and / or storage (including when on display at the retailer).

[0096] Laminate formulation

[0097] The first and second layers are laminated together using an adhesive mixture of solventless polyurethane and SMBS as the active ingredient. If required, an ethylene scavenger can also be included. Many chemical ethylene scavengers are known to those skilled in the art and can be incorporated at the concentration recommended by the supplier.

[0098] The concentration of the adhesive can be from about 30% to about 90% weight / weight (w / w) with the SMBS concentration being from 10% to about 70% (w / w).

[0099] The diameter of the SMBS microparticles is typically from about 1 pm to about 250 pm.

[0100] The coating weight of the applied adhesive layer can be from 1 GSM to about 100 GSM.

[0101] Other application methods

[0102] Sealing film adhesive on punnet

[0103] This product uses the same materials and ranges as the SO2 generating multilayer film described above, with the main difference being the method of sealing the punnet containing the fruit and / or vegetables with the product. The adhesive is applied to the punnet or the SO2 generating multilayer film and the film is then applied to the punnet to form a seal, instead of heat sealing the SO2 generating multilayer film to the punnet. Although a heat sealable layer can still be used, in this case the SO2 generating multilayer film does not require a heat sealable layer. The adhesive used can be any food safe adhesive, including cold seal adhesives, pressure sensitive adhesives, peelable adhesives, etc.

[0104] Example 1

[0105] Heat seal product

[0106] The following preservation and / or fungal inhibition heat seal devices were tested in a blueberry trial:

[0107] 1. Laminate a first layer of perforated heat sealable PET film of about 5 pm to about 20 pm thick to a second layer of unperforated PET film of about 5 pm to about 20 pm thick with an adhesive mix of 45% to 60% SMBS to 40% to 55% adhesive (where the coating weight is about 15 GSM to 30 GSM and the SMSB particle size is about 20 pm to 50 pm). Use a perforation hole size of 1 mm to 5 mm - HS 8.1

[0108] 2. Laminate a first layer of heat sealable PET film of about 5 pm to about 20 pm thick with a strip of perforations (having 50 mm of unperforated area over the length of the punnet) to a second layer of unperforated PET film of about 5 pm to about 20 pm thick with an adhesive mix of 45% to 60% SMBS to 40% to 55% adhesive (where the coating weight is about 15 GSM to 30 GSM and the SMSB particle size is about 20 pm to 50 pm). Use a perforation hole size of 1 mm to 5 mm - HS 8.2

[0109] 3. Laminating a first layer of heat sealable PET film of about 5 microns to about 20 microns thick to a second layer of unperforated PET film of about 5 microns to about 20 microns thick with an adhesive mixture having 45% to 60% SMBS to 40% to 55% adhesive (wherein the coating weight is about 10 GSM to 20 GSM and the SMSB particle size is about 20 microns to 50 microns) - HS7.1

[0110] 4. Laminating a first layer of heat sealable PET film of about 5 microns to about 20 microns thick to a second layer of unperforated PET film of about 5 microns to about 20 microns thick with an adhesive mixture having 45% to 60% SMBS to 40% to 55% adhesive (wherein the coating weight is about 12 GSM to 20 GSM and the SMSB particle size is about 20 microns to 50 microns) - HS7.2

[0111] Pathology test

[0112] Materials and Methods

[0113] The efficacy of heat seal prototypes selected from above was tested in vitro by exposing spores and mycelial plugs of Botrytis cinerea and Alternaria alternata to the technology. Each pathogen and treatment was performed in triplicate over a 7 day time period.

[0114] Results

[0115] Results are shown in Figure 1 and Figure 2 .

[0116] Blueberry test

[0117] Materials and Methods

[0118] Preparation of pathogen inoculum

[0119] To obtain a spore suspension of Botrytis cinerea, the fungus was grown on Potato Dextrose Agar (39 g.L -1 , PDA, Merck) at 20°C for 7 days. Spores were collected from the surface of the plates by adding 10 mL of sterile distilled water to the culture plate and gently scraping the surface with a sterile hockey stick. The collected spore suspension was then filtered through a single layer of sterile coffee filter to prepare a stock solution. The spore concentration was counted by using a hemocytometer. The inoculum was prepared on the same day of the inoculation of the fruits.

[0120] Infection technique

[0121] Each blueberry fruit was wounded three times using a sterile wound scarer, approximately 200 blueberries were wounded. The wounded berries were placed in a fruit cup and inoculated by spraying with freshly prepared Botrytis suspension. The berries were sprayed until the spore suspension overflowed. These berries were air dried in laminar flow for 45 minutes. To promote spore germination, the cups containing the inoculated berries were placed in a black bag with a wet paper towel to increase humidity and stored at 20°C for 22 hours.

[0122] Plant material and storage conditions

[0123] Blueberries were obtained and kept fresh at 4°C upon delivery. For each treatment, 12 heat-seal punnets were used. Eight of these heat-seal punnets were filled with two blueberry clamshells to produce 300g heat-seal punnets, and four of these heat-seal punnets were filled with five blueberry clamshells to produce 750g heat-seal punnets. This was done to monitor the effect of berry number on efficacy. Each heat-seal punnet was then filled with two / inoculated berries, heat-sealed according to the treatments listed in Table 1, and kept cold at 4°C for three days. Treatments and controls were kept fresh in separate storage rooms. After 3 days of cold storage, 2 x 300g heat-seal punnets and 1 x 750g heat-seal punnet were evaluated for each treatment. The remaining punnets were stored at 10°C and evaluated after 3, 5 and 7 days in similar groups to the 3 days cold storage to mimic retail storage.

[0124] Table 1: Treatments used in this trial

[0125]

[0126]

[0127] Results and discussion

[0128] Figure 3 and Figure 4 show the percentage of rot development for 300g and 750g heat-seal punnets, respectively. Rot development increased over time. When evaluated after 3 days of cold storage, the initial percentage of rot was low, however, as the shelf life was extended, rot development increased. At the end of the shelf life, the untreated control had more rot development compared to all treatments. In Figure 3 , all berries treated with different heat-seal films showed less rot development when compared to the control. The full micro-perforation treatment with / without additional ventilation holes and the striped micro-perforation treatment without additional ventilation holes were the most effective on 300g punnets during storage. In Figure 4 , the lowest amount of rot was detected in the full micro-perforation treatment, when the punnets were filled to 750g, the highest amount of rot was observed in the striped micro-perforation + ventilation holes treatment when compared to the other treatments.

[0129] The inhibition efficacy of each treatment was calculated as the weight of rotting berries relative to the weight of the untreated control berries. The highest percentage of inhibition was detected in 750 g punnets treated with the full micro-perforated heat-seal film after 3 days of cold storage. This treatment also had the highest rot inhibition over the different shelf life intervals. For 300 g punnets, the highest rot inhibition was observed in the full micro-perforated and strip micro-perforated + hole treatments after 3 days of cold storage. However, over the shelf life period, the strip micro-perforated treatment had the highest average percentage of rot inhibition followed by the full micro-perforated treatment. The percentage of rot inhibition is inversely linear to the percentage of rot development, therefore the results of the percentage of inhibition correspond to the percentage of rot development (Table 2).

[0130] Table 2. Percentage of inhibition of treatments in 300 g and 750 g heat-seal punnets under cold storage and shelf life.

[0131]

[0132]

[0133] Conclusions

[0134] The results obtained from the trial indicate that the different prototypes evaluated were effective for different berry weights. The full micro-perforated film was the most effective in controlling rot in berries in 750 g punnets. However the trial results indicate that all berries treated with the different heat-seal films showed less rot development when stored in 300 g punnets compared to the control. A correlation between rot development and SO2 emissions can be drawn. Treatments with higher SO2 emissions had less rot development, indicating that the released SO2 inhibited the growth of Botrytis cinerea on the berries. Studies have shown that SO2 limits the production of proteins and enzymes required for pathogen development. The SO2 emissions were higher in 750 g punnets compared to the emissions detected in 300 g punnets. This smaller headspace (the space between the berries and the heat-seal film) results in a smaller volume for the release of SO2 gas particles, which results in a higher concentration of SO2 gas produced.

[0135] Example 2

[0136] Flow-wrapped products

[0137] The product uses the same materials and range, the main difference being the application method. Instead of being sealed onto the punnet, the product is flow-wrapped onto the punnet and sealed to itself to make a complete enclosure of the punnet containing the berries and the laminated product.

[0138] The following trial of the flow-wrapped apparatus was conducted using blackberries.

[0139] 1. Laminating 10 to 20 micron BOPP first layer to 10 to 20 micron BOPP second layer with adhesive mixture of 45 to 60% SMBS to 40 to 55% adhesive (where coating weight is about 10 GSM to 20 GSM and SMSB particle size is about 20 micron to 50 micron)-FSL 7

[0140] 2. Laminating 15 to 25 micron BOPP first layer to 15 to 25 micron BOPP second layer with adhesive mixture of 45 to 60% SMBS to 40 to 55% adhesive (where coating weight is about 10 GSM to 20 GSM and SMSB particle size is about 20 micron to 50 micron)-FSL 8

[0141] 3. Laminating 20 to 40 micron BOPP first layer to 20 to 40 micron BOPP second layer with adhesive mixture of 45 to 60% SMBS to 40 to 55% adhesive (where coating weight is about 10 GSM to 20 GSM and SMSB particle size is about 20 micron to 50 micron)-FSL 9

[0142] Flow wrapped pathology test

[0143] Materials and Methods

[0144] In this particular example, the SO2 film tested was hand flow wrapped by cutting it to size and wrapping these around punnets containing 125g blackberries. The film was then sealed around the punnets using a heat sealer. The blackberry punnets were initially held in cold storage at 2°C for up to 5 days, after which the flow wrapping process was applied and the flow wrapped punnets stored for a further 7 days at a shelf life temperature of 15°C. It should be noted however that the flow wrapping can be applied directly after picking and this can be the preferred method.

[0145] Results

[0146] The results are shown in Figure 5

[0147] Example 3

[0148]

[0149]

[0150] 1. Introduction

[0151] ​Blueberry fruit crops are mainly sold fresh worldwide, with cold storage being the most effective method used to limit losses in the short term. The significant growth in global demand for blueberries puts the industry under great pressure to find ways to extend the storage life of this crop, which can create market opportunities and increase exports. Blueberries are perishable and easily damaged, with fruit rot caused by fungal pathogens being the main factor limiting the storage and shelf life of blueberries. Sulfur dioxide (SO2) gas is commonly used for table grapes to prevent rot during storage, either by fumigating the fruit from the field first and then fumigating the storage room every week, or by the presence of pads containing sodium metabisulfite in the packaging. These SO2 pads are composed of a series of laminated plastic films glued together by a layer of wax or a solvent-free adhesive containing the exact concentration and particle size of SMBS. The moisture in the fruit packaging is absorbed by the pads and reacts with the sulfite to produce SO2.

[0152] Recently, the use of SO2 gas has been investigated as a potential postharvest solution for blueberry rot. However, to achieve the full potential of this technology, several factors must be considered, as the kinetics of SO2 releasing pads can be influenced. These factors include the quality of the fruit, the appropriate exposure time and concentration, the time elapsed between picking and gassing, the temperature and relative humidity (RH) in the packaging and storage room, the fruit variety, the packaging material, the amount of berries and the free space inside the carton, and the handling of the cold chain during storage. The type and method of SO2 generation must be carefully chosen, as high concentrations of gas can affect the biochemical and sensory properties of the fruit and are harmful to humans and the environment at high doses.

[0153] In view of the above, the experiment aimed to evaluate the efficacy of different heat-seal films and flow-wrapped films in reducing Botrytis rot on blueberries without affecting other quality parameters.

[0154] 2. Objectives

[0155] To evaluate the efficacy of PET heat-seal and flow-wrapped prototypes on Botrytis rot development on blueberries during cold storage and shelf life at retail.

[0156] 3. Materials and Methods

[0157] 3.1.1. Preparation of the pathogen inoculum

[0158] To obtain a spore suspension of Botrytis cinerea, the fungus was grown on Potato Dextrose Agar (39 g.L -1 , PDA, Merck) at 20°C for 7 days. Spores were collected from the surface of the plates by adding 10 mL of sterile distilled water to the culture plate and gently scraping the surface with a sterile hockey stick. The collected spore suspension was filtered through a single layer of sterile coffee filter. The spore concentration was counted by using a hemocytometer. The inoculum was prepared on the same day of the infection.

[0159] 3.1.2. Infection technique

[0160] Each fruit was wounded with a sterile wound scarifier. 20 ul of freshly prepared Botrytis suspension was placed into each wound. The berries were placed in laminar flow to air dry for 45 minutes.

[0161] 3.1.3. Test packaging and storage conditions

[0162] High quality blueberries were obtained from six 33 blueberry growers. For each treatment (Table 3 and Table 4), nine heat-seal punnets were used per treatment. Single inoculated Botrytis berries were added to each heat-seal punnet containing blueberries. Pre-cut heat-seal film for each treatment was placed on top of the respective punnet. For flow-wrapped treatments, the punnets were closed and sealed. Berries were moved to a cold room at 0.5°C. After 7 days at 0.5°C, all punnets were removed. Thereafter, 1 punnet per treatment was removed for evaluation. The remaining with heat-seal film and flow- wrapped were moved to 10°C. The same procedure was followed for the 4 and 7 day shelf-life studies (10°C).

[0163] Table 3: Heat-seal treatment list

[0164] Treatment Prototype 1 7-layer SO2 sheet - "Vivo 1" 2 5-layer SO2 sheet - "Tomasys" 3 3-layer SO2 sheet - "Fast Fresh" 4 Heat sealed 8.1 full perforated 5 Heat sealed 7.1 thin coating 6 Control

[0165] Table 4: Flow-wrapped treatment list

[0166]

[0167]

[0168] 4. Quality measures

[0169] 4.1.1 Postharvest rot

[0170] Rotted berries were weighed and expressed as a percentage per sample. No pathogen was identified in this experiment and the focus was mainly on the percentage of berries that could not be sold due to postharvest rot in general.

[0171] 4.1.2. Sulphur dioxide / SO2 emissions

[0172] Damaged berries were counted and expressed as a percentage per sample. SO2 emissions were measured at each evaluation period.

[0173] 5. Results and discussion

[0174] 5.1.1. Postharvest rot

[0175] Heat-seal

[0176] All products were highly effective against Botrytis. There were no significant differences between all treatments except Fast Fresh which showed significantly more rot development after 7 days of shelf life Figure 6 Both Heat Seal 8.1 (full perforated) and 7.1 (thin coating) showed more than 80% effectiveness after all storage periods Figure 7

[0177] Botrytis development was significantly increased for the control compared to SO2 treatment from 4 to 7 days of shelf life. This can be attributed to the membrane releasing SO2 gas over time at the required dose, which sterilizes the berry surface by killing and eliminating any actively growing pathogenic spores during cold storage and shelf life storage. SO2 gas reacts with the water content of the product and forms sulfurous acid of low pH. Sulfurous acid (H2SO2) reacts with cell membranes and blocks the enzymes of microorganisms by reducing essential disulfide (-S-S-) linkages.

[0178] Flow wrapping

[0179] All treatments were highly effective against Botrytis development after cold storage and shelf life. FSL 13 was the most effective of the prototypes tested Figure 8 and Figure 9 ).

[0180] 5.1.2. Sulphur dioxide / SO2 emissions

[0181] Heat sealing

[0182] The results showed that berries treated with full perforated Heat Seal 8.1 and Heat Seal 7.1 thin coating did not show SO2 damage during all storage periods. The 5 layer SO2 sheet - Tomasys heat seal film caused the highest percentage of damage, followed by 7 layer SO2 sheet - Vivo 1 and 3 layer SO2 sheet - Fast Fresh Figure 10 ).

[0183] Flow wrapping

[0184] The results showed that berries treated with FSL-12 only showed SO2 damage during shelf life storage, increasing with increasing shelf life storage days. FSL 13 only showed SO2 damage after 7 days. For FSL-12 at perforation, very low to no SO2 damage was recorded after 4 and 7 days of shelf life storage. Berries treated with the remaining treatments included could not be sold due to high percentage of SO2 damage Figure 11 ).

[0185] 6. Conclusion

[0186] ​The results obtained from the trials indicate that the different heat seal prototypes evaluated were effective against development of Botrytis on the berries. Both heat seal 8.1 (full perforation) and 7.1 (thin coating) showed more than 80% effectiveness after all storage periods. In comparison to SO2 treatment, the control showed a significant increase in Botrytis development from 4 to 7 days of shelf life.

[0187] The flow-wrapped berries treated with FSL indicate that all treatments were highly effective against Botrytis development after cold storage and shelf life. However, FSL 13 was the most effective prototype against Botrytis rot tested in the trial. FSL-12 showed a decrease in efficacy when perforation holes were included, although it was still effective.

[0188] In summary, both heat seal prototypes tested have the potential to reduce postharvest losses in blueberries without affecting the appearance or other quality parameters of the blueberries. However, for the flow-wrapped prototypes, perforation holes should be included to prevent SO2 damage due to the higher gas release concentration, although effective.

[0189] Example 4

[0190]

[0191]

[0192] 1. Introduction

[0193] Fruits and vegetables serve as suitable substrates for fungal pathogens that cause rotting during storage and transport, making the fruits unsuitable for trade purposes, resulting in huge postharvest economic losses. Botrytis is considered the most important postharvest fungal pathogen causing significant losses in fresh fruits, vegetables, and ornamentals. It can attack a wide range of crops using various modes of infection. The fungus can also develop under conditions during storage, shipping, and trade, making control of this disease a challenge. Picked crops are particularly susceptible to Botrytis infection because, unlike tissues with vigour, picked produce is senescing rather than growing. Another major postharvest disease causing significant losses is the Alternaria fruit rot. This disease is caused by the filamentous fungus Alternaria alternata. The infection of Alternaria occurs when the fruit is damaged or becomes vulnerable during long-term storage. Control of Alternaria includes the use of fungicides, however, the negative effects of residual fungicides in edible fruits and vegetables on human health are undeniable, necessitating the search for alternative control products.

[0194] Due to the low health risk and availability of SO2 generating pads, extensive research has been conducted on alternative uses of SO2 generating pads as a fungicide. In response to the industry call for "active packaging" that can reduce the waste of pre-packaged fresh fruits and vegetables, the present applicant has sought to develop a SMBS coated heat seal film and flow wrap film to provide protection for fresh produce from farm to consumer. These are intended to help maintain the quality of the fruit, extend the shelf life, prevent rot development and reduce food loss and waste. The proposed technology is different from the commercial technology currently used in the form of SO2 pads as it involves a SMBS coated heat seal film or flow wrap film for punnets. Unlike existing heat seal films and flow wrap films, the new SMBS coated product will be biodegradable or 100% recyclable. Because the technology is new and will be used for fresh tomatoes, it is important to understand the release profile of the prototypes. The present applicant has developed different types of pads in which the rate of SO2 is controlled. There are two different release phases (fast and / or slow) and many different sizes of pads are available. PET heat sealable film and flow wrap film are preferred as these are recyclable as these can be used are punnets. Therefore, the efficacy of SO2 containing heat sealable PET film and flow wrap PET film against Botrytis cinerea was investigated.

[0195] 2. Objectives

[0196] To evaluate the efficacy of PET heat seal and flow wrap prototypes against Botrytis cinerea rot development on tomatoes during cold storage and shelf life.

[0197] 3. Materials and Methods

[0198] 3.1.1. Preparation of pathogen inoculum

[0199] To obtain a spore suspension of Botrytis cinerea, the fungus was grown on Potato Dextrose Agar (39 g.L -1 , PDA, Merck) at 20°C for 7 days. Spores were collected from the surface of the plates by adding 10 mL of sterile distilled water to the culture plate and gently scraping the surface with a sterile hockey stick. The collected spore suspension was filtered through a single layer of sterile coffee filter. The spore concentration was counted by using a hemocytometer. The inoculum was prepared on the same day of the infection.

[0200] 3.1.2. Infection technique

[0201] Each tomato was wounded with a sterile wound scarifier. 20 ul of freshly prepared Botrytis cinerea suspension was placed into each wound. These tomatoes were placed in a laminar flow to air dry for 45 minutes.

[0202] 3.1.3. Test packaging and storage conditions

[0203] For each treatment (Table 5 and Table 6), nine heat-seal trays were used for each treatment. Three inoculated Botrytis tomatoes were added to each heat-seal and flow-wrap tray. The pre-cut heat-seal film of each treatment was placed on top of the tray. For flow-wrap treatments, the tray was closed with the film and sealed. The tomato trays were moved to a cold room at 10 °C. After 7 days at 10 °C, all trays were removed. One tray of each treatment was removed for evaluation. The remaining, still with heat-seal film and flow-wrap, were moved to 18 °C. The same procedure was followed for the 4-day and 7-day shelf-life studies (18 °C).

[0204] Table 5: Heat-seal treatment list

[0205]

[0206]

[0207] Table 6: Flow-wrap treatment list

[0208] Treatment Prototype 1 7-layer SO2 sheet - "Vivo 1" 2 5-layer SO2 sheet - "Tomasys" 3 3-layer SO2 sheet - "Fast Fresh" 4 FSL 12 5 FSL 13 6 FSL 12 - 2 perforated 7 FSL 12 - 4 perforated 8 Control

[0209] 4. Quality measures

[0210] 4.1.1 Postharvest decay

[0211] To determine the percent inhibition, the lesion diameter of the inoculated area was measured with a digital caliper.

[0212] 4.1.2. Sulfur dioxide / S02 emissions

[0213] Damaged berries were expressed as yes / no.

[0214] 5. Results and discussion

[0215] 5.1.1. Postharvest decay

[0216] Heat-seal

[0217] All five SO2 products were highly effective against Botrytis growth. There were no significant differences between the two prototypes for a specific heat-seal prototype during the entire storage period. As the storage period increased, the efficacy decreased, however, both Heat-seal 8.1 (fully perforated) and 7.1 (thin coating) still showed more than 70% effectiveness after all storage periods. Figure 12

[0218] Flow-wrap

[0219] ​Similar results were shown for flow-wrapping treatments. The prototypes included were highly effective against development of Botrytis after 4 days shelf life. However, when shelf life storage was increased to 7 days, the efficacy of the specially formulated flow- wrapped prototypes (T4 to T7) decreased significantly. This trend was more pronounced when perforations were added to FSL 12. This prototype with 4 perforation holes was the least effective of all treatments Figure 13

[0220] 5.1.2. Sulphur dioxide / SO2 emissions

[0221] Heat-seal

[0222] Results showed that tomatoes treated with the fully perforated heat-seal 8.1 showed slight SO2 damage signs (Table 7). The thin-coat heat-seal 7.1 did not show SO2 damage over all shelf life periods. However, 7-layer SO2 sheet - Vivo 1, 3-layer SO2 sheet - Fast Fresh and 5-layer SO2 sheet - Tomasys resulted in severe SO2 damage causing the fruits to be unsalable.

[0223] Flow-wrapping

[0224] Due to the higher emissions released by flow-wrapping treatments, results reflected more severe SO2 damage, especially for the 7-layer SO2 sheet - Vivo 1, 3-layer SO2 sheet - Fast Fresh and 5-layer SO2 sheet - Tomasys treatments. Tomatoes treated with FSL 12, FSL 12 + 2 holes and FSL 13 showed slight SO2 damage over all shelf life periods. FSL 12 did not result in SO2 damage when perforated with 4 holes.

[0225] Table 7: SO2 damage of tomatoes treated with heat-seal films.

[0226] Treatment SO2 injury 7-layer SO2 sheet - Vivo 1 Yes 5-layer SO2 sheet - Tomasys Yes 3-layer SO2 sheet - Fast Fresh Yes Heat sealed 8.1 full perforated Yes Heat sealed 7.1 thin coating No Control No

[0227] 6. Conclusion

[0228] Results obtained from the trial showed that the different heat-seal prototypes evaluated were effective against Botrytis development on tomatoes. Both heat-seal 8.1 (fully perforated) and 7.1 (thin-coat) showed more than 70% effectiveness after all shelf life periods. Efficacy decreased but not significantly as shelf life storage was increased to 7 days. Tomatoes treated with flow-wrapping films showed that FSL 12 and FSL 13 were highly effective. However, as perforations were increased, the efficacy of FSL-12 decreased as shelf life storage was extended.

[0229] The trial showed that flow-wrapping bags with few perforations can be the most successful in limiting SO2 damage.

[0230] ​In summary, the trials showed that 7.1 (thin coating) heat seal and FSL 12+2 hole flow wrap could be suitable products for reducing postharvest losses of tomatoes without affecting other quality parameters.

Claims

1. A preservation and / or anti-fungal device for fresh fruits and / or vegetables, including tomatoes, grapes, soft fruits, berries including blueberries, strawberries, raspberries and blackberries, wherein the device comprises: a packaging container comprising a punnet for containing the fruit and / or vegetable; and a sulfur dioxide (SO2)-generating multilayer lamination film adapted to seal the packaging container by a first operatively inwardly facing layer of the multilayer lamination film in sealable contact with an open end of the packaging container after the fruit and / or vegetable is packed in the packaging container; wherein the SO2-generating multilayer lamination film comprises: (i) a first operatively inwardly facing layer and a second operatively outwardly facing layer, each comprising a material selected from the group comprising: A. a thermoplastic material, B. a material coated with a thermoplastic coating comprising a heat seal lacquer selected from the group comprising a binder comprising a copolymer, an inorganic crosslinking agent, a solventless polyester resin or a copolyester aqueous dispersion, and a filler, or C. a non-thermoplastic polymer or paper without a thermoplastic coating; and (ii) an inner adhesive layer between the first layer and the second layer, having a coating weight of about 1 GSM to about 100 GSM or any sub-range contained therein, comprising an adhesive composition comprising a polyurethane adhesive composition comprising a solventless polyurethane adhesive composition at a concentration of about 30% to about 90% weight / weight (w / w) or any sub-range contained therein; and sodium metabisulfite (SMBS) microparticles having a diameter of about 1 pm to about 250 pm or any sub-range contained therein at a concentration of about 10% to about 70% (w / w) or any sub-range contained therein; and optionally a chemical ethylene scavenger selected from the group comprising potassium permanganate, zeolite, activated carbon or pumice, wherein, when the first operatively inwardly facing layer comprises a material selected from a non-thermoplastic polymer or paper without a thermoplastic coating, the edge of the open end of the packaging container or the edge of the operatively inwardly facing layer in contact with the edge of the open end of the packaging container is coated with an adhesive comprising a cold seal adhesive, a pressure sensitive adhesive or a peelable adhesive.

2. The fresh keeping and / or anti-fungal device according to claim 1, wherein the first operatively inwardly facing layer and / or the second operatively outwardly facing layer is selected from the group comprising paper, including Kraft paper or single side light bleached Kraft (MGBK) paper; a polyolefin film comprising biaxially oriented polypropylene (BOPP), low density polyethylene (LDPE), high density polyethylene (HDPE); or a polyester film comprising polyethylene terephthalate (PET), and wherein the first layer and the second layer have the same or different materials.

3. The fresh keeping and / or anti-fungal device according to claim 1 or claim 2, wherein the first operatively inwardly facing layer and / or the second operatively outwardly facing layer comprises: (i) a polyolefin film layer ranging from about 9 pm to 150 pm or any sub-range contained therein; or (ii) a paper layer without a thermoplastic coating. (ii) a paper layer ranging from about 13 GSM to 300 GSM or any sub-range contained therein; or (iii) a polyester film ranging from about 3 pm to 100 pm or any sub-range contained therein.

4. The fresh-keeping and / or anti-fungal device according to any one of the preceding claims, wherein the polyolefin film or polyester film layer of the first operatively inwardly facing layer comprises a heat sealable material or has the heat seal lacquer applied thereto.

5. The fresh-keeping and / or anti-fungal device according to any one of claims 1 to 3, wherein the paper layer of the first operatively inwardly facing layer is coated with a heat seal lacquer or adhesive to make it sealable to the packaging container.

6. The fresh-keeping and / or anti-fungal device according to any one of the preceding claims, wherein the packaging container comprises a substrate comprising a recycled substrate selected from the group comprising foil, a polymer comprising PET or BOPP, or paper, pulp or card.

7. The fresh-keeping and / or anti-fungal device according to any one of the preceding claims, wherein the first operatively inwardly facing layer and / or the second operatively outwardly facing layer is micro-perforated and the micro-perforations range in diameter from about 0.05 mm to 2.8 mm or any sub-range contained therein.

8. The fresh-keeping and / or anti-fungal device according to any one of claims 1 to 6, wherein the first operatively inwardly facing layer and / or the second operatively outwardly facing layer is macro-perforated and the macro-perforations range in diameter from about 2 mm to 100 mm or any sub-range contained therein.

9. The fresh-keeping and / or anti-fungal device according to claim 7 or 8, wherein the SO2 generating multi-layered film comprises selected areas or zones with micro-perforations and selected areas or zones with macro-perforations.

10. The fresh-keeping and / or anti-fungal device according to any one of the preceding claims, wherein either or both of the first operatively inwardly facing layer and the second operatively outwardly facing layer are treated with one or more additional treatments selected from the group comprising an anti-fog treatment, a corona treatment or a chemical treatment for ink adhesion.

11. The fresh-keeping and / or anti-fungal device according to any one of the preceding claims, wherein the first operatively inwardly facing layer and / or the second operatively outwardly facing layer comprises a substantially transparent polymer.

12. The fresh-keeping and / or anti-fungal device according to any one of the preceding claims, wherein the concentration of the solventless polyurethane adhesive composition is from about 40% to about 80% (w / w), or from about 50% to about 70% (w / w), and the sodium metabisulfite (SMBS) microparticles have a diameter of from about 10 pm to about 70 pm, or from about 20 pm to about 50 pm, and a concentration of from about 40% to about 80% (w / w), or from about 50% to about 70% (w / w).

13. The fresh keeping and / or anti-fungal device according to any one of the preceding claims, wherein the paper is coated on one or both surfaces with any one or more of a WVTR or OTR control coating, or a hydrophobic coating, a hydrophilic coating, or a primer coating, or wherein the paper is uncoated.

14. The fresh keeping and / or anti-fungal device according to any one of the preceding claims, wherein the paper is coated on one or both surfaces with a polyolefin film comprising BOPP, LDPE, or HDPE, or a polyester film comprising PET, such that when the paper is coated on one surface, the inner adhesive layer is coated on the coated surface of the paper.

15. The fresh keeping and / or anti-fungal device according to any one of the preceding claims, wherein the first or second polyolefin film layer has a thickness ranging from 10 pm to 50 pm or 10 pm to 30 pm, and the first or second polyester film layer has a thickness ranging from 10 pm to 50 pm or 10 pm to 30 pm.

16. A preservation and / or anti-fungal device for use during the transport or storage of fresh fruit and / or vegetables, including tomatoes, grapes, soft fruit, berries including blueberries, strawberries, raspberries and blackberries, wherein the device comprises: a packaging container comprising a punnet for containing the fruit and / or vegetables; and a multi-layer laminated film that generates sulfur dioxide (SO2), the multi-layer laminated film being adapted for flow-wrapping the packaging container with the multi-layer laminated film such that a first operatively inwardly facing layer of the multi-layer laminated film is in contact with an open end of the container after the fruit and / or vegetables are packaged in the container; and wherein the SO2 generating multi-layer laminated film comprises: (i) the first operatively inwardly facing layer and a second operatively outwardly facing layer, each comprising a polymer selected from the group comprising a polyolefin film comprising biaxially oriented polypropylene (BOPP), low-density polyethylene (LDPE), high-density polyethylene (HDPE); or a polyester film comprising polyethylene terephthalate (PET); and (ii) an inner adhesive layer between the first layer and the second layer, the inner adhesive layer having a coating weight of about 1 GSM to about 100 GSM or any sub-range contained therein, comprising an adhesive composition, including a polyurethane adhesive composition, further including a solventless polyurethane adhesive composition, at a concentration of about 30% to about 90% weight / weight (w / w) or any sub-range contained therein; and sodium metabisulfite (SMBS) microparticles having a diameter of about 1 pm to about 250 pm or any sub-range contained therein at a concentration of about 10% to about 70% (w / w) or any sub-range contained therein; and optionally a chemical ethylene scavenger selected from the group comprising potassium permanganate, zeolite, activated carbon, or pumice.

17. The fresh keeping and / or anti-fungal device according to claim 16, wherein the first operatively inwardly facing layer and / or the second operatively outwardly facing layer comprises a polyolefin film layer ranging from about 9 pm to 150 pm or any sub-range contained therein; or a polyester film ranging from about 3 pm to 100 pm or any sub-range contained therein. ​ 18. The fresh keeping and / or anti-fungal device of claim 16 or 17, wherein the concentration of the solventless polyurethane adhesive composition is about 40% to about 80% (w / w), or about 50% to about 70% (w / w) or any sub-range contained therein, and the sodium metabisulfite (SMBS) microparticles have a diameter of about 10 pm to about 70 pm, or about 20 pm to about 50 pm, or any sub-range contained therein and have a concentration of about 40% to about 80% (w / w), or about 50% to about 70% (w / w), or any sub-range contained therein.

19. The fresh keeping and / or anti-fungal device of any one of claims 16 to 18, wherein the thickness of the first or second polyolefin film layer ranges from 10 pm to 50 pm or 10 pm to 30 pm or any sub-range therein, and the thickness of the first or second polyester film layer ranges from 10 pm to 50 pm or 10 pm to 30 pm or any sub-range therein.

20. A method of manufacturing a SO2 generating multi-layered laminated film for use in the fresh keeping and / or anti-fungal device of the present invention, comprising the steps of: (i) providing a first operatively inwardly facing layer comprising: A. a thermoplastic material, B. a material coated with a thermoplastic coating comprising a heat seal lacquer selected from a binder comprising a copolymer, an inorganic crosslinking agent, a solventless polyester resin or a copolyester aqueous dispersion and a filler, or C. a non-thermoplastic polymer or paper without a thermoplastic coating; and (ii) applying an adhesive layer to the first substrate material layer using a laminator or a coater, the adhesive layer having a coating weight of about 1 GSM to about 100 GSM or any sub-range contained therein, comprising an adhesive composition, including a polyurethane adhesive composition, including a solventless polyurethane adhesive composition, having a concentration of about 30% to about 90% weight / weight (w / w) or any sub-range contained therein; and sodium metabisulfite (SMBS) microparticles having a diameter of about 1 pm to about 250 pm or any sub-range contained therein, having a concentration of about 10% to about 70% (w / w) or any sub-range contained therein; (iii) laminating a second operatively outwardly facing layer comprising: A. a thermoplastic material, B. a material coated with a thermoplastic coating comprising a heat seal lacquer selected from a binder comprising a copolymer, an inorganic crosslinking agent, a solventless polyester resin or a copolyester aqueous dispersion and a filler, or C. a non-thermoplastic polymer or paper without a thermoplastic coating; onto the adhesive layer using a laminator, such that the adhesive layer is sandwiched between the first layer and the second layer.

21. The method of claim 20, wherein when the first operatively inwardly facing layer comprises a material selected from a non-thermoplastic polymer or a paper without a thermoplastic coating, the method further comprises the additional step of coating the operatively inwardly facing surface of the first layer with a thermoplastic coating comprising a heat seal lacquer selected from a group comprising a binder comprising a copolymer, an inorganic crosslinking agent, a solventless polyester resin, or a copolyester aqueous dispersion, and a filler.

22. The method of claim 20 or claim 21, wherein the adhesive layer further comprises a chemical ethylene scavenger selected from a group comprising potassium permanganate, zeolite, activated carbon, or pumice.

23. The method of any of claims 20-22, wherein the first operatively ground-facing layer and / or the second operatively ground-facing layer comprises: paper, including Kraft paper or MGBK paper; polyolefin film comprising BOPP, LDPE, HDPE; or a polyester film comprising PET, and wherein the first and second layers comprise the same or different materials.

24. The method of claim 23, wherein the first operatively inwardly facing paper layer and / or the second operatively outwardly facing paper layer has a thickness ranging from about 13 GSM to about 300 GSM or any sub-range contained therein; the first operatively inwardly facing polyolefin layer and / or the second operatively outwardly facing polyolefin film layer has a thickness ranging from 9 pm to 150 pm or any sub-range contained therein; and the first operatively inwardly facing polyester layer and / or the second operatively outwardly facing polyester film layer has a thickness ranging from 3 pm to 100 pm or any sub-range contained therein.

25. The method of any one of claims 20 to 24, further comprising a step wherein the first operatively inwardly facing layer and / or the second operatively outwardly facing layer is micro-perforated comprising by hot needle perforation, cold needle perforation, or laser perforation, before or after the layers are laminated to form the SO2 generating multi-layer laminate film.

26. The method of claim 25, wherein the micro-perforations have a diameter ranging from about 0.05 mm to 2.8 mm or any sub-range contained therein.

27. The method of any one of claims 20 to 24, further comprising a step wherein the first operatively inwardly facing layer and / or the second operatively outwardly facing layer is macro-perforated comprising by hot needle perforation, cold needle perforation, or laser perforation, before or after the layers are laminated to form the SO2 generating multi-layer laminate film.

28. The method of claim 27, wherein the macro-perforations have a diameter ranging from about 2 mm to 100 mm or any sub-range contained therein.

29. The method of any one of claims 20 to 28, comprising a step wherein the first operatively inwardly facing layer and / or the second operatively outwardly facing layer is both micro-perforated and macro-perforated, and the micro-perforations and / or the macro-perforations are arranged in areas or zones of the SO2 generating multi-layer laminate film as desired by the user.

30. The method according to any one of claims 20 to 29, wherein the method further comprises one or more treatment steps comprising an anti-fog treatment, a corona treatment or a chemical treatment for ink adhesion.

31. A method of preserving fresh fruit and / or vegetables including tomatoes, grapes, soft fruit, berries including blueberries, strawberries, raspberries and blackberries, packaged in containers or punnets during transport and / or storage or inhibiting fungal growth in fresh fruit and / or vegetables packaged in containers or punnets using a preservation and / or anti-fungal device according to any one of claims 1 to 19.

32. A preservation and / or anti-fungal device according to any one of claims 1 to 19 substantially as herein described with reference to any one of the illustrative examples.

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