WO2019154860A1

WO2019154860A1 - Polymer film for food packaging

Info

Publication number: WO2019154860A1
Application number: PCT/EP2019/052913
Authority: WO
Inventors: Eusebiu Grivei; Bertrand DE BACKER; Vanessa DE WOLF; Sylvain DESPREZ
Original assignee: Nano4
Priority date: 2018-02-07
Filing date: 2019-02-06
Publication date: 2019-08-15
Also published as: EP3749518A1; FR3077563A1; FR3077563B1; LU101435B1; LU101435A1

Abstract

A packaging polymer film for slowing down the ripening process of fruit and/or vegetables comprises a resin, in particular made of a low-density polyethylene, and an ethylene-absorbing compound encapsulated in the resin.

Description

Polymer film for food packaging

The present invention relates to a polymer film, in particular a plastic film, for example monolayer or multilayer, for food packaging having good properties for the preservation of fruits and / or vegetables, including bananas and tomatoes during transport and / or storage.

According to one aspect, the present invention provides a polymer film for packaging food articles, in particular a polymer film having a thickness greater than or equal to 10 μm and less than or equal to 100 μm, in which the polymer film comprises an absorbent layer. , in particular permeable to gases, the absorbent layer comprising a resin, especially a thermoplastic resin, in particular low density polyethylene, and an ethylene absorber compound encapsulated in the resin wherein the ethylene absorber compound comprises a diatom. In other aspects, the present invention provides: a plastic masterbatch for manufacturing the absorbent layer of a polymeric film as defined in the first aspect, wherein the plastic masterbatch comprises a resin, especially polyethylene, and the diatom , in particular where the diatomaceous earth is present in the plastic masterbatch in a total amount of 5 to 50%, preferably 10 to 40%, by dry weight on the basis of the total dry mass of the masterbatch; a method of producing a plastic layer for use as an absorbent layer of a polymeric film as defined in the first aspect, the method comprising:

the melting of granules comprising a thermoplastic resin and an ethylene absorber compound wherein the ethylene absorber compound is a diatom present in a total amount of from 5% to 30%, preferably from 15% to 25% by dry weight on basis of the total dry mass of the granulate

- the dilution of the previous melted mixture with the thermoplastic resin

- mixing and extrusion of the previously obtained mixture; and a use of a polymer film as defined in the first aspect for slowing the ripening of fruits and / or vegetables due to ethylene during transport and / or storage when the polymeric film serves as a fruit package and or with vegetables,

especially for the preservation of bananas and tomatoes during transport

SUBSTITUTE SHEET (RULE 26) and / or storage. The dependent claims provide preferred or alternative embodiments.

Ethylene acts as a plant hormone capable of accelerating the ripening of fruits and vegetables. As fruits and vegetables become mature they eject ethylene gas, and if these fruits and vegetables are kept in an airtight container, the ethylene remains trapped in the container and by its presence accelerates the maturation fruits and vegetables and cause degradation of their properties. It is therefore important to be able to reduce the amount of ethylene in contact with fruits and vegetables, especially during transport periods, including transport by cargo and / or truck, and / or storage, in order to limit the maturation process. and alteration of these fruits and vegetables. A commonly used solution for absorbing ethylene is the use of closed sachets comprising, inter alia, potassium permanganate which by a chemisorption process will capture ethylene. A major disadvantage of this method is that potassium permanganate can not be in contact with food and therefore requires the use of these sachets to contain potassium permanganate. Even in this case, contact with food, for example following a possible rupture of a bag, could not be excluded.

Surprisingly, it has been found that it is possible to slow the ripening of fruits and / or vegetables, including bananas and tomatoes, due to ethylene during transport, including cargo transport. and / or truck, and / or storage, using a polymer film, in particular a plastic film, of monolayer or multilayer packaging comprising a layer comprising a resin, in particular a thermoplastic resin, encapsulating ethylene absorbers being diatoms, including CelaWhite ™ and / or Celatom ^® LCS-3 and / or Super Floss Celite ^® and particularly where the layer has a thickness greater than or equal to 10 pm and less than or equal to 100 pm.

The ethylene absorber compound may comprise, consist essentially of or consist of diatoms. In one aspect the diatoms have a BET surface area> 15.0 m ² / g,> 17.0 m ² / g,> 20.0 m ² / g,> 25.0 m ² / g and / or <200 m ² / g, <170 m ² / g, <130 m ² / g, <100 m ² / g, <80 m ² / g, <50 m ² / g, <45 m ² / g, <40 m ² / g, <35 m ² / g, or <30 m ² / g. Diatoms As an absorber of ethylene, unlike potassium permanganate, they absorb ethylene via physisorption. The diatoms serving as an ethylene absorber have the advantage of being thermally stable, unlike potassium permanganate. Diatoms have the advantage of being approved for contact with food as required by the European Food Safety Authority (EFSA) and / or the US Food and Drug Administration (FDA). Diatoms also have the advantage of being able to absorb gases other than ethylene, in particular diatoms can also advantageously absorb unhealthy gases. The diatomaceous earth ethylene absorber may comprise a catalyst, including an ethylene cracking catalyst. Preferably diatoms include, consist essentially of, or consist of CelaWhite ™ and / or Celatom ^® LCS-3 and / or Super Floss Celite ^®.

In another aspect, the diatoms can be encapsulated in paint and advantageously absorb the gases generating bad odors.

As used herein, the term "consists or substantially consists of" is intended to limit the scope of a statement or claim to specified materials or steps and those that do not materially affect the fundamental and novel features of the invention.

The absorbent layer comprises, consists essentially of or consists of a resin, especially a thermoplastic resin, and the ethylene absorber compound wherein the ethylene absorber compound is encapsulated in the resin. The absorbent layer may comprise a catalyst, especially an ethylene cracking catalyst. The absorbent layer has in particular a thickness> 10 mhh,> 15 mhh,> 20 mΐti,> 25 mΐti and / or <100 mΐti, <85 mΐti, <70 míti, <55 míti, <40 míti, <30 míti.

In the absorbent layer, the ethylene absorber compound is especially present in an amount>1%,>2%,> 3% and / or <30%, <25%, <20%, <17%, <15%, <13%, <10%, <8% dry weight based on the total dry weight of the resin encapsulating the ethylene absorber and the ethylene absorber compound. The resin encapsulating the ethylene absorber comprises, consists essentially of, or consists of a natural resin or a synthetic resin. Preferably the resin encapsulating the ethylene absorber comprises, consists essentially of, or consists of a thermoplastic resin. The thermoplastic resin is selected from the group consisting of low density polyethylene (LDPE), high density polyethylene (HDPE), polypropylene (PP), polyvinyl chloride (PVC), polyethylene terephthalate (PET), polycarbonate (PC), polystyrene (PS), polyamide (PA), ethylene vinyl alcohol (EVOH), polyvinylidene chloride (PVDC), polylactic acid (PLA), and mixtures thereof. Preferably the thermoplastic resin comprises, consists essentially of, or consists of low density polyethylene. The resin encapsulating the ethylene absorber may also comprise, consist essentially of, or consist of, latex.

The polymer film may be a monolayer polymer film consisting of the resin, especially the thermoplastic resin, comprising the ethylene absorber. The polymeric film may be a multilayer polymeric film, i.e. comprising at least two layers and wherein at least one layer of the multilayer polymeric film consists of the resin comprising the ethylene absorber. In one aspect of the invention the multilayer polymeric film may be a two-layer polymeric film; the resin layer comprising the ethylene absorber which may be the food contact layer or the outer layer. In another aspect of the invention the polymer film is a multilayer polymeric film comprising at least three polymeric layers of which at least one layer is the resin comprising the ethylene absorber. The resin layer comprising the ethylene absorber may be an outer layer, i.e., the inner layer in contact with food, or the outer layer, i.e., the diaper the furthest away from the food, or the resin layer comprising the ethylene absorber may be an intermediate layer of said multilayer polymeric film having at least three layers.

In the multilayer polymeric films, the layers not consisting of the layer consisting of the resin comprising the ethylene absorber, are preferably polymeric layers comprising, consisting essentially of or consisting of resins, especially thermoplastics, permeable to gases. The gas-permeable thermoplastic resins are selected from the group consisting of low density polyethylene (LDPE), high density polyethylene (HDPE), polypropylene (PP), polyvinyl chloride (PVC), polyethylene terephthalate (PET) ), polycarbonate (PC), polystyrene (PS), polyamide (PA), ethylene vinyl alcohol (EVOH), polyvinylidene chloride (PVDC), polylactic acid (PLA), and mixtures thereof . Preferentially, the gas permeable thermoplastic resins comprise, consist essentially of, or consist of low density polyethylene. Layers not consisting of the resin layer comprising the ethylene absorber may also comprise, consist essentially of, or consist of, paper layers, especially kraft paper. These layers, which do not consist of the layer consisting of the resin comprising the ethylene absorber, have in particular thicknesses> 10 mIT,> 15 mITI,> 20 mITI,> 25 mITI and / or <100 mITI, <85 mITI, < 70 mIT, <55 mITI, <40 mITI, <30 mITI.

Preferably, the polymer film comprises only materials approved for contact with food as required by the European Food Safety Authority (EFSA) and / or the US Food and Drug Administration (FDA). ). Advantageously, the polymer film can be reused several times, unlike sachets containing potassium permanganate.

The absorbent layer, when the absorbent layer consists of a thermoplastic resin encapsulating the ethylene absorber, may be produced by a method comprising:

the melting of granules comprising the thermoplastic resin and the ethylene absorber compound wherein the ethylene absorber compound is a diatom, in particular a total amount> 5%,> 7%,> 10%,> 12%,> 15 % and / or <40%, <30%, <27%, <25%, <22%, <20% dry mass on the basis of the total dry mass of the granulate

the dilution of the preceding melted mixture with thermoplastic resin, and

- mixing and extrusion of the previously obtained mixture. The method of manufacturing the monolayer plastic film or multilayer can be achieved by methods known in the field of plastic film manufacturing. The method may include the extrusion, in particular simultaneous or sequential, of the different layers. In particular, each layer may be obtained by melting the resin and / or granules corresponding to the desired composition for said layer, the kneading, and in particular the extrusion of the layer in the desired shape, via a die.

Granules comprising, consisting essentially of or consisting of the thermoplastic resin and the ethylene absorber compound may be produced by a method comprising:

- mixing the thermoplastic resin in a molten state with the ethylene absorber compound

withdrawing the water or the steam from the mixture of ethylene absorber compound and the thermoplastic resin in the molten state, and

- Solidification of the previously obtained mixture, especially in the form of granules.

During the production of the granules comprising the thermoplastic resin and the ethylene absorber compound, so that the ethylene absorber compound is not saturated with water or water vapor when it is encapsulated in the thermoplastic resin, it is It is preferable to remove water and / or water vapor from the mixture of the thermoplastic resin in a molten state with the ethylene absorber compound. The step of controlling and / or removing the water during the encapsulation of the ethylene absorber in the thermoplastic resin can be carried out by methods known to those skilled in the art. For example, the production of the granules may comprise mixing the thermoplastic resin in a molten state with the ethylene absorber compound in an extruder equipped with a water vapor pumping system released during mixing.

Embodiments of the invention will now be described, by way of example only, with reference to the accompanying images.

Figure 1 is a representation of the maturation of a banana in a film three-layer plastic according to the invention; and

Figure 2 is a representation of a comparative example.

Example 1:

The maturation of 2 bananas after 15 days was observed when stored in a 3-layer plastic film. In the comparative example (FIG. 2) the 3 layers consist of low density polyethylene, whereas in the example according to the invention, the inner layer is a layer of low density polyethylene where the ethylene absorber is encapsulated. the ethylene absorber being the CetWhite ™ diatom, and wherein the ethylene absorber content in the intermediate layer is 5% dry mass based on the total dry mass of the thermoplastic resin encapsulating the ethylene absorber compound and the ethylene absorber compound of the inner layer. In the comparative example and in accordance with the invention, all the layers have a thickness of 20 μm.

In Figure 2, we can clearly see that after 15 days of storage in a conventional plastic film, the banana has become ripe with several black spots already present. In comparison, in Figure 1, after 15 days of storage in a plastic film according to the invention, the banana has matured much less and has much less black spots, confirming that the banana had suffered less the effect of the ethylene.

[0021] Figure 3 shows a representation of a WolfsensePro volatile organic compound (VOC) measurement system having a resolution of about 5 ppb VOC, including ethylene. The TG 502 sensor (1) was introduced into a measuring chamber (2) of approximately 15 liters filled with a quantity of ethylene. Then the switch of the ethylene inlet is closed and the ethylene quantity is recorded as a function of time, measuring the decrease in the amount of ethylene due to leakage. A first experiment is performed to measure the decrease in the amount of ethylene in the measurement chamber (2) due to system leakage. In a second experiment is measured the decrease of the amount of ethylene in the measurement chamber due to leakage but in the presence of a plastic film comprising an ethylene absorber in the measuring chamber. Figure 4 represents the amount of ethylene (in ppb on the y-axis) as a function of time (in hours on the abscissa) for the comparative example, ie without the presence of plastic film encapsulating the ethylene absorber.

Figure 5 shows the amount of ethylene (in ppb on the y-axis) as a function of time (in hours on the x-axis) in the presence of a monolayer film of low density polyethylene where is encapsulated the ethylene absorber, the ethylene absorber being the CetWhite ™ diatom, and wherein the ethylene absorber content is 20% by dry weight based on the total dry mass of the thermoplastic resin encapsulating the absorber compound ethylene and the ethylene absorber compound. The plastic film has a total mass of 20 g, a size of about 30 x 20 cm, and a thickness of 100 μm.

FIG. 6 represents the difference between the curves of FIGS. 4 and 5. The curve demonstrates the absorption of ethylene until reaching a saturation threshold (the ethylene absorbers being already saturated with ethylene). followed by a decrease in the amount of ethylene in the container.

In other aspects, the invention provides defined embodiments as follows:

A polymeric film for packaging food articles, in particular a polymer film having a thickness greater than or equal to 10 μm and less than or equal to 100 μm, in which the polymer film comprises an absorbent layer, in particular a gas-permeable layer, the absorbent layer comprising a resin, especially a thermoplastic resin, especially low density polyethylene, and an ethylene absorber compound encapsulated in the resin wherein the ethylene absorber compound comprises a diatom.

The polymer film of embodiment 1, wherein the polymer film comprises:

- an inner layer,

at least one intermediate layer, and

an outer layer,

or the inner layer and / or an intermediate layer comprises a polymer film according to embodiment 1, and

the other layers comprise a gas-permeable resin, in particular a thermoplastic resin, in particular of low-density polyethylene.

3. Polymer film according to embodiment 1 or 2, wherein the diatom has a specific surface area greater than or equal to 15.0 m ² / g and less than or equal to 50.0 m ² / g as measured by the BET method. 4. Polymer film according to any one of embodiments 1 to 3, wherein the diatom is present in a total amount of 1 to 20%, preferably 3 to 8%, by dry weight on the basis of the total dry mass of the absorbent layer.

5. The polymeric film according to any one of embodiments 1 to 4, wherein the diatom comprises CelaWhite ™ and / or Celatom ^® LCS-3 and / or Super Floss Celite ^®.

6. Plastic masterbatch for manufacturing a plastic film according to any one of embodiments 1 to 5, wherein the plastic masterbatch comprises a resin, especially polyethylene, and the diatom, especially where the diatom is present in the masterbatch plastic in a total amount of 5 to 50%, preferably 10 to 40%, by dry mass on the basis of the total dry mass of the masterbatch. 7. Food items, in particular bananas or tomatoes, packaged with a polymer film according to any one of embodiments 1 to 5.

A method of producing a plastic layer for use as an absorbent layer according to any one of embodiments 1 to 5, the method comprising:

the melting of granules comprising a thermoplastic resin and an ethylene absorber compound where the ethylene absorber compound is a diatom present in a total amount of 5% to 30%, preferably 15% to 25% by dry mass based on the total dry mass of the granule

- the dilution of the previous melted mixture with the thermoplastic resin

- mixing and extrusion of the previously obtained mixture.

9. Method of producing a granule comprising a resin

thermoplastic and an ethylene absorber compound wherein the ethylene absorber compound is a diatom present in a total amount of 5% to 30%, preferably 15% to 25% by dry weight based on the total dry mass of the granule , the granule may in particular be used in the method according to embodiment 8, the method comprising:

solidification of the mixture obtained previously.

10. Use of the polymer film according to any one of embodiments 1 to 5 for slowing the ripening of fruits and / or vegetables due to ethylene during transport and / or storage when the polymer film serves as a fruit package and / or vegetables, especially for the preservation of bananas and tomatoes during transport and / or storage.

Claims

claims

1. Polymeric film for packaging food articles, in particular a polymer film having a thickness greater than or equal to 10 μm and less than or equal to 100 μm, in which the polymer film comprises an absorbent layer, in particular a gas-permeable layer, the absorbent layer comprising a resin , especially a thermoplastic resin, especially low density polyethylene, and an ethylene absorber compound encapsulated in the resin wherein the ethylene absorber compound comprises a diatom.

The polymeric film of claim 1, wherein the polymeric film comprises:

- an inner layer,

at least one intermediate layer, and

an outer layer,

or

the inner layer and / or an intermediate layer comprises the absorbent layer, and

The polymeric film of claim 1 or 2, wherein the diatom has a specific surface area greater than or equal to 15.0 m ² / g and less than or equal to 50.0 m ² / g as measured by the BET method.

4. A polymer film according to any one of claims 1 to 3, wherein the diatom is present in a total amount of 1 to 20%, preferably 3 to 8%, by dry weight on the basis of the total dry mass of the absorbent layer.

5. The polymeric film according to any one of claims 1 to 4, wherein the diatom comprises CelaWhite ™ and / or Celatom ^® LCS-3 and / or Super Floss Celite ^®.

6. Plastic masterbatch for manufacturing the absorbent layer of a polymeric film according to any one of claims 1 to 5, wherein the plastic masterbatch comprises a resin, especially polyethylene, and the diatom, especially where the diatom is present in the plastic masterbatch in a total amount of 5 to 50%, preferably 10 to 40%, by dry weight on the basis of the total dry mass of the masterbatch.

A method of producing a plastic layer for use as an absorbent layer of a polymeric film according to any one of claims 1 to 5, the method comprising:

- the dilution of the previous melted mixture with the thermoplastic resin

- mixing and extrusion of the previously obtained mixture.

A method of producing a pellet for use in the method of claim 7, the pellet comprising a thermoplastic resin and an ethylene absorber compound wherein the ethylene absorber compound is a diatom present in a total amount of 5% at 30%, preferably from 15% to 25% by dry weight on the basis of the total dry mass of the granule, the method comprising:

solidification of the mixture obtained previously.

9. Use of the polymer film according to any one of claims 1 to 5 for slowing the ripening of fruits and / or vegetables due to ethylene during transport and / or storage when the polymer film serves as a fruit packaging and / or vegetables, especially for the preservation of bananas and tomatoes during transport and / or storage.