DE202018107140U1 - Insert for food packaging - Google Patents

Abstract

, Multi-layered absorbent mat as an insert for food packaging with a base layer (3), a layer of an absorbent material (4) based on cellulose fibers and a cover layer (2), wherein the base layer (3) and the cover layer (2) on at least 2 sides projecting over the layer of absorbent material (4) and at least the cover layer (2) is permeable to liquids, characterized in that the absorbent material contains a decomposition CO-supplying compound and citric acid and / or tartaric acid.

Description

The present invention relates to a multi-layered absorbent mat as a liner for food packaging with a base layer, a layer of an absorbent material and cover layer, wherein the base layer and the cover layer project over at least 2 sides of the layer of absorbent material and at least the cover layer is permeable to liquids and a food packaging from a multi-layered suction mat and an outer packaging.

A major cause of food spoilage in unopened packages is the oxygen that remains in the package during the packaging process. An improvement in the shelf life of food offers the so-called protective gas packaging (Modified Atmosphere Packaging). The introduction of inert or inert gases, the protective gases, during packaging, the oxygen is largely displaced from the pack, which can increase the shelf life of the food in the unopened packaging many times.

Fresh fish is a particularly sensitive and economically valuable food. The aim is to bring the fish as so - called fresh fish on the market, which requires that the fish must not be exposed to extreme temperature fluctuations from the time of catch until sale and also the contact with oxygen should be avoided if possible, is the protective gas packaging for Fresh fish especially suitable.

Fish is usually packed in boxes or crates, to optimize the storage conditions of the boxes or boxes of CO _{2 is} added, ie the fish is stored under CO ₂ atmosphere. However, the fish consumes the protective CO ₂ during transport and storage.

It is an object of the present invention to provide a material suitable for use in packaging, with which the consumption of CO ₂ by the fresh fish can be wholly or partly compensated in order to optimally store the fish until it is sold or consumed.

The present invention is a multi-layered absorbent mat as a liner for food packaging with a base layer, a layer of an absorbent material based on pulp fibers and a cover layer, wherein the base layer and the cover layer project over at least 2 sides of the layer of absorbent material and at least the Cover layer is permeable to liquids, which is characterized in that the absorbent material contains a decomposition CO ₂ -derfernde compound and citric acid and / or tartaric acid.

The multi-layer absorbent mat according to the invention has the advantage that it contains pulp fibers as absorption material, which also have a good absorption capacity compared to saline water. In order to counteract the decomposition of CO ₂ , the absorption layer contains a compound which gives CO ₂ by contact with an acid in an aqueous or moist environment and an acid approved in the field of food processing, such as citric acid and / or tartaric acid, hereinafter referred to as acid. As soon as melt water is formed or water escapes from the stored fish, the CO ₂ -producing and the acid dissolve and react with each other to form CO ₂ . The formed carbon dioxide ensures that the fish is stored continuously under CO ₂ and from the outside no or as little as possible oxygen penetrates.

The CO ₂ -dermitting compound and the acid can be used in the form of commercial qualities, as they also apply to the food industry. Suitable CO _2- supplying compounds are in particular the alkali metal carbonates and alkali metal bicarbonates, for example Na ₂ CO ₃ , K ₂ CO ₃ , NaHCO ₃ and KHCO ₃ , the sodium compounds being particularly preferred. Preferably, the CO ₂ -derfernde compound and the acid in the form of solids, for example in powder form, are used. The CO ₂ -emitting compound and the acid are preferably used in equimolar amounts. The amount of CO ₂ needed depends on the volume of the packaging, the type of fish and the surface of the fish. The person skilled in the art can calculate, based on the required amount of CO _2, the respective amounts of CO ₂ -containing compound and acid which should be present in the absorbent mat.

Essential for the absorption of liquid emerging from the fish and optionally melt water is the present invention layer of an absorbent material. This is preferably selected from a non-woven or fabric-like material based on plastic or pulp. Pulp-based nonwoven materials having good absorption capacity are preferred. These are inexpensive and commercially available materials that are easy to work with. As pulp materials, any of the pulp materials known in the art may be used, such as Fluff Pulp (FP), Mechanical Pulp (MP), TMP (Thermomechanical Pulp), CTMP (Chemithermomechanical Pulp), HT-CTMP (High Temperature Chemithermomechanical Pulp), Wood Pulp and fluff pulp and any mixtures of the above Pulps. Particularly good results are obtained with FP, a standardized defiberized product with a fiber length of approximately between 1 and 10 mm, in particular 5 and 10 mm, CTMP, for example a CTMP, as described by the method in US Pat WO91 / 12367 or HT-CTMP obtainable by a method according to WO95 / 34711 ,

As a particularly suitable absorption layers so-called airlaid webs or tissue papers have been found. Airlaid nonwovens are preferably substantially irregularly arranged fibers of cellulose or cellulose. In a particularly preferred embodiment, the individual fibers or layers of fibers are joined together by pressing in some areas with compression of the fibers in the compressed areas. By pressing the pulp fibers in sections, the cellulose or pulp acquires a certain strength, without reducing the absorption properties of the material for liquids. The stability of the layer of absorbent material can be further increased if it has on the top and / or on the bottom another layer of thin tissue or fleece. In one possible embodiment, the tissue layer can be compacted in regions together with the fibers of cellulose or cellulose. The production of such interconnected pulp fibers and fiber layers or webs is described in the German patent applications DE19824825 . DE19803837 . DE19750890 and in the European patent EP1032342 described by way of example. The airlaid nonwovens usually have a basis weight of 60 and 900 g / m ² , preferably in the range of 90 to 900 g / m ² and in particular from 120 to 700 g / m ² . In the event that the absorption capacity of a single layer of airlaid nonwoven should not be sufficient, the absorbent according to the invention may also have two or more layers of airlaid nonwoven or other absorbent bodies or materials.

The CO ₂ delivering compound and the acid are preferably incorporated homogeneously within the layer of absorbent material so that the reaction between the two components can proceed as soon as they are dissolved. If so-called airlaid nonwovens are used as absorbing layer, the CO _2- supplying compound and the acid are generally mixed directly with the starting fibers for the airlaid process, so that CO _2- supplying compound and acid are also simultaneously from the fibers be kept in the airlaid nonwoven.

In one possible embodiment, the absorbent layer for increasing the absorbent capacity may contain additional absorbent materials, for example superabsorbent materials. These superabsorbent materials are preferably incorporated homogeneously within the layer of absorbent material, so that a uniform absorption of the liquid can be achieved. If so-called airlaid nonwovens are used in combination with superabsorbent materials as the absorbent layer, these superabsorbents are usually mixed directly with the starting fibers for the airlaid process, so that the superabsorbers are also simultaneously held by the fibers in the airlaid nonwoven. The superabsorbent materials can be selected from any superabsorbent, usually selected from crosslinked polyacrylic acid, carboxymethyl cellulose (CMC), pectins or gelatin polymers.

In a further possible embodiment, the cover layer and the cover layer project beyond the layer of the absorbent material on at least two sides. These protruding layers of material can be used to partially or completely cover the food. In order to cover the food as completely as possible, it is advantageous for the regions projecting beyond the layer of absorbent material to project beyond the width of the absorbent layer by at least 50%, wherein the base layer and the liquid-permeable cover layer on at least 2 sides the layer of absorbent material overhang,

In one possible embodiment, the base layer and / or the cover layer protrude on all sides beyond the layer of absorbent material, wherein the areas projecting beyond the layer of absorbent material may have different sizes. The areas overlying the layer of absorbent material should be sized to achieve full food coverage and spill protection for liquids.

The base layer according to the invention can consist of a suitable polymer material, preferably of a thermoplastic plastic. Suitable materials for this base layer are in particular high, medium or low density polyethylene, high, medium or low density polypropylene, copolymers of different polyolefins, especially polyethylene and polypropylene, polyethylene terephthalate, polyesters, biodegradable films of polylactic acid or based on Starch and coextrudates or composite materials from the above-mentioned plastic materials into consideration. The base layer may be impermeable or permeable to liquids, in which case it may be perforated, for example perforated, needled, punched or scored.

As a further layer, the absorbent mat according to the invention has a cover layer, which is arranged above the layer of absorbent material. The foods to be stored are deposited on this top layer. The topcoat serves to rapidly transport meltwater and other liquids toward absorbent material. The cover layer is usually made of nonwoven, paper or made of the above materials for the base layer, which should be permeable to liquids and z. B. are perforated, such as perforated, needled, punched or scratched

In a preferred embodiment of the present invention, the base layer and the cover layer are the same or different. The cover layer is permeable to liquids, but it can also be permeable to both layers, ie the base layer and the cover layer for liquids.

The individual layers, from which the absorbent mat according to the invention is constructed, are usually connected to one another by gluing, wherein at the edges the respective overlying regions of the cover layer and the base layer abut each other directly and are connected to one another via the adhesive. This bond between topcoat and basecoat should be impermeable to the absorbed liquids.

As already described, the absorbent mat according to the invention can be used in particular for food packaging for fresh fish. It serves primarily for insertion in trays and boxes or boxes.

Another object of the present invention is accordingly a food packaging of a multi-layered absorbent mat, as described above, and an outer packaging. The outer package is preferably designed such that it has a bearing surface for food, for example, to receive fresh fish in the entire length. In particular, in the storage and transport of fresh fish ice is placed in the packaging in addition to the fish to temper the fish at about 0 ° C. In order to prevent any melt water from emerging from the outer packaging, the absorbent mat is preferably larger in size than the bearing surface of the outer packaging. The absorbent mat should be sized so that the foodstuffs stored in the package are virtually covered by the mat, i. H. can be packed. But it is sufficient if the layer of absorbent material is slightly smaller or equal to the bearing surface of the outer packaging. In this way it is ensured that the exiting liquid in the direction of the packaging bottom, d. H. down, exits and absorbs.

• 1 eine Seitenansicht einer erfindungsgemäßen Saugmatte,
• 2 einen Schnitt durch eine Lebensmittelverpackung mit eingelegter Saugmatte,
• 3 eine Draufsicht auf die erfindungsgemäße Saugmatte.

An embodiment of the present invention will be described below with reference to the drawings. Show it:

• 1 a side view of a suction mat according to the invention,
• 2 a section through a food package with inserted suction mat,
• 3 a plan view of the absorbent mat according to the invention.

In 1 is a suction mat 1 showing an upper liquid permeable cover layer and a lower liquid impermeable film layer 3 having. Between the cover layer 2 and the film layer 3 is the layer of absorbent material 4 , hereinafter also referred to as Absorptionslage arranged. The absorption layer 4 has here shown as dashed undirected fibers 5 as well as the CO _2- supplying compound 6a and citric acid 6b in the form of powder or granules.

According to the invention, the upper cover layer 2 and the upper foil layer 3 larger dimensions than the absorption layer 4 , The outer areas 7 . 8th the topcoat 2 and the film layer 3 , ie their edges, protrude over the edge 9 the absorption layer 4 out.

The absorption layer 4 is a fibrous layer of pulp fibers. In the embodiment shown here, the absorbent layer shows a three-dimensional structure in which the film has a plurality of uniformly distributed depressions 10 has inside. In the embodiment shown here, the walls run 10a the depressions 10 conically towards the inside. This layer 4 is preferably made in an airlaid process of cellulosic material. This cellulosic material is available inexpensively as a mass material. When produced in a continuous airlaid process, the fibrous web is produced from a bed of cellulose pulp fibers (fluff pulp) piled up in an airstream and possibly interspersed CO ₂ -containing compound and citric acid (shown here as 6a and 6b). For the production of a standardized commodity one can make use of the renewable raw materials available on the market.

The process of pulping in the air stream as the starting material for the fiber layer 4 allows a dry processing of the pulp fibers and a good compaction of the pulp fibers in individual, ie discrete areas 10 , Outside such areas 10 lie the fibers 5 loose together, what in these zones the Absorbency and the flexibility of the layer 4 improved. In the embodiment shown here, the absorbent layer has on its top and bottom another layer of thin fleece. These layers can be pressed together with the pulp fibers, whereby a connection between the fibers and the possibly present upper and / or lower layer is obtained.

The cover layer 2 is usually much thinner than the fiber layer 4 , The layer 3 For example, it can be formed from a web of textile, nonwoven or film-like material. It serves to quickly move the exiting liquid in the direction of the absorption layer 4 to transport.

Bonding the fibers of the layer 4 and the optional cover fleece 12 . 13 for the absorption layer 4 For example, in an embossing process. This results in a partial compression under compression of the pulp fibers of the fiber layer 4 ,

The compression is not large-uniform, but a pressing is mainly in embossing areas 10 instead, taking recesses 11 in the fiber layer 4 form. The wells 11 in the embossing areas 10 can be round or polygonal. In the embodiment shown here, they have the shape of truncated pyramids or truncated cones.

The embossing is done by means of two rollers, one of which with the wells 11 forming structure is provided. This way, in the discrete stamping areas 10 achieved a compression of the pulp fibers. Outside the stamping areas 10 The fibers lie loosely together, which improves the absorption capacity and the flexibility of the material.

The joining of the three layers according to the invention, covering layer 2 , Absorption layer 4 and base layer 3 usually by gluing. For this purpose, it has proved to be advantageous for the production process, if the absorption layer provided with a suitable adhesive, for. B. is sprayed, and the other layers are then applied. The layers, cover layer and base layer projecting beyond the absorption layer are likewise glued together. In an alternative embodiment, the cover layer and the base layer are coated with adhesive and applied to the absorption layer, via the applied adhesive, the areas of the cover layer and the base layer projecting beyond the absorption layers can likewise be connected.

The weight per unit area of the absorbent mat according to the invention 1 may be between 20 g / m ² and 600 g / m ² . The basis weight is preferably between 220 g / m ² and 550 g / m ² .

2 shows a section through a food packaging in which the absorbent mat according to the invention has been inserted. The individual layers are preferably connected to each other in order to prevent slippage against each other. In the illustration in 2 The individual layers of the suction mat were exploded to illustrate the structure. The packaging is a box in the embodiment shown here 14 which is preferably foldable and may have a lid (not shown here). The absorbent mat 1 is in the box 14 inserted. The absorption layer 4 has about the size of the soil 15 the box, the edges 7 . 8th the topcoat 2 and the film layer 3 protrude above the absorption layer 4 out and are bigger than the ground 15 , These outer areas 7 . 8th of topcoat 2 and foil layer 3 are used to line the cardboard and, provided the outer areas 7 . 8th Sufficient, the food in the box 14 be stored, wrap.

3 represents a view of the absorbent pad from above, the layer 4 made of absorbent material is between the cover layer 2 and the base layer 3 arranged and shown in dashed lines. In the embodiment illustrated here, the length of the regions is 7 . 7 ' at least 50% of the edge lengths a1 . a3 , The areas 8th . 8th' protrude in the embodiment shown here with a smaller supernatant beyond the absorbent layer, preferably the supernatant corresponds 8th . 8th' at least the height of the box 14 , The food gets on the area of the absorption layer 4 who is usually on the ground 15 is laid. The edge A4 is over the edge a1 beaten, analogous to the edge A2 over the edge a3 the absorption layer, so that the food is covered. The edges A1 and A3 The absorbent pad can when the areas 8th . 8th' big enough along the edges a2 and a4 be taken. Usually, these areas become 8th . 8th' folded up and are arranged almost parallel to the wall of the box. Preferably, if the protruding areas have a different size, these smaller areas should at least have the height of the wall of the box, so that the edges A1 and A3 finish with the edges of the box or overhang it slightly.

LIST OF REFERENCE NUMBERS

1

suction pad

2

Upper cover layer

3

Lower foil layer

4

absorbent layer

5

fiber

6a

CO ₂ delivering compound (□)

6b

Citric acid (△)

7

Outer region of the cover layer 2

8th

Outer region of the film layer 3

9

Edge of the absorbent layer 4

10

stamping area

11

deepening

12

Cover fleece of the absorbent layer 4

13

Cover fleece of the absorbent layer 4

14

box

15

Bottom of the box

A1, A2, A3, A4

Edges of the absorbent pad

a1, a2, a3, a4

Edges of the absorption layer 2

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• WO 9112367 [0009]
• WO 9534711 [0009]
• DE 19824825 [0010]
• DE 19803837 [0010]
• DE 19750890 [0010]
• EP 1032342 [0010]

Claims (12)

, Multi-layered absorbent mat as an insert for food packaging with a base layer (3), a layer of an absorbent material (4) based on cellulose fibers and a cover layer (2), wherein the base layer (3) and the cover layer (2) on at least 2 sides projecting over the layer of absorbent material (4) and at least the cover layer (2) is permeable to liquids, characterized in that the absorbent material contains a decomposition CO ₂ -containing compound and citric acid and / or tartaric acid. Absorbent mat after Claim 1 , characterized in that the compound delivering the CO ₂ and the citric acid and / or tartaric acid are arranged in the form of solids between the pulp fibers. Absorbent mat after Claim 1 or 2 , characterized in that the layer of absorbent material (4) consists essentially of irregularly arranged cellulose fibers (5), which are partially interconnected by compression with compression of the pulp fibers (5) in the compressed areas (10). Absorbent mat after Claim 3 , characterized in that the pulp fibers in the compressed areas (10) are pressed under heat. Absorbent mat after one of Claims 3 or 4 , characterized in that in the production of the absorbent material (4) neither adhesives nor other binders are used. Absorbent mat after one of Claims 1 to 5 characterized in that the base layer (3) is selected from a thermoplastic, in particular high, medium or low density polyethylene, high, medium or low density polypropylene, copolymers of different polyolefins, especially polyethylene and polypropylene, polyethylene terephthalate, Polyester, Biodegradable films of polylactic acid or based on starch, coextrudates from the above-mentioned plastic materials. Absorbent mat after one of Claims 1 to 7, characterized in that the liquid-permeable cover layer (2) is selected from nonwoven or tissue. Food packaging from a multi-layered absorbent mat according to one of Claims 1 to 8th and an outer packaging (12). Food packaging after Claim 9 , characterized in that the outer packaging has a support surface (13) for food. Food packaging according to one of the Claims 9 or 10 , characterized in that the suction mat (1) in the outer package (12) is inserted. Food packaging according to one of the Claims 9 to 11 , characterized in that the suction mat (1) is dimensioned larger than the support surface (13) of the outer packaging and thus the contents can be completely hit (12). Food packaging according to one of the Claims 9 to 12 , characterized in that the layer (4) of absorbent material is slightly smaller than or equal to the support surface (13) of the outer packaging (12).

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