PACKAGING WRAPPER FOR FOOD PRODUCTS

Abstract

The packaging wrapper for gluten-free food products includes a multilayer sheet, including in turn one layer of polymeric material having at least one aperture and a layer of porous filter material coupled to the layer of polymeric material and positioned so as to cover the aperture.

Claims

1. A packaging wrapper for gluten-free food products, comprising a multilayer sheet (11), comprising in turn at least one layer of polymeric material (12) having at least one aperture (14) and a layer of filter material (13) coupled, by means of adhesive (15), to the layer of polymeric material (12) and positioned so as to cover said aperture (14), said layer of filter material (13) being porous and comprising a plurality of layers of fibrous material overlapping each other so as to prevent the passage of allergens, in particular gluten, wherein the filter material (13) has a thickness between 50 and 200 μm, the size of the pores of the filter material (13) is between 1 μm and 100 μm, and the polymeric material (12), the filter material (13) and the adhesive (15) are resistant to temperatures up to at least 200° C., preferably up to 220° C., for a period of between 5 and 30 minutes, preferably between 10 and 20 minutes.

2. The packaging wrapper as in claim 1, wherein said wrapper is for cooking said gluten-free food products in an oven.

3. The packaging wrapper as in claim 1, wherein the polymeric material (12), the filter material (13) and the adhesive (15) are resistant to differences in temperature from −30° C. to 250° C. for an interval of time from 0 to 2 minutes, in particular from 0 to 30 seconds.

4. The packaging wrapper as in claim 1, wherein the layer of filter material (13) is conformed so as to be rough or crinkled.

5. The packaging wrapper as in claim 1, wherein the layer of filter material (13) is distanced by two opposite edges (11B) of the multilayer sheet (11) so as to leave uncovered two flaps (12A) of polymeric material (12).

6. The packaging wrapper as in claim 1, wherein the multilayer sheet (11) comprises two overlapping layers of polymeric material (12) provided with respective apertures (14) overlapping each other, the layer of filter material (13) being disposed between the two layers of polymeric material (12).

7. The packaging wrapper as in claim 1, wherein it comprises inside it a food product, in particular gluten-free, more particularly gluten-free bread.

8. The packaging wrapper as in claim 1, wherein the polymeric material (12) is punched.

9. The packaging comprising at least one gluten-free food product packaged in a packaging wrapper as in claim 1.

10. The packaging as in claim 9, wherein said gluten-free food product has the following crunchiness parameters: force between 2500 and 6000 g, linear distance between 25 and 90.

11. The packaging as in claim 9, wherein said gluten-free food product is frozen.

12. The packaging as in claim 9, wherein said gluten-free food product is cooked in an oven.

13. A method to produce a packaging wrapper for gluten-free food products, by means of flow pack, starting from a multilayer sheet (11) comprising a layer of polymeric material (12) provided with apertures (14) and a layer of filter material (13) coupled, by means of adhesive (15), to the layer of polymeric material (12) and positioned so as to cover said aperture (14), said layer of filter material (13) being porous and comprising a plurality of layers of fibrous material overlapping each other, wherein the filter material (13) has a thickness between 50 and 200 μm, the size of the pores of the filter material (13) is between 1 μm and 100 μm, and the polymeric material (12), the filter material (13) and the adhesive (15) are resistant to temperatures up to at least 200° C., preferably up to 220° C., for a period of between 5 and 30 minutes, preferably between 10 and 20 minutes.

14. The method to cook gluten-free food products, said method comprising cooking, in an oven, at least one gluten-free food product already packaged in a packaging wrapper as in claim 1.

15. The method as in claim 13, wherein said gluten-free food product is in a frozen condition when it is subjected to cooking in an oven.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0034] These and other aspects, characteristics and advantages of the present invention will become apparent from the following description of some embodiments, given as a non-restrictive example with reference to the attached drawings wherein:

[0035] FIG. 1 is a perspective view of a packaging wrapper according to the present invention;

[0036] FIGS. 2 and 3 are plan views, respectively of two surfaces of a sheet for producing the packaging wrapper of FIG. 1;

[0037] FIG. 4 is a section view of the sheet of FIGS. 2 and 3 taken along section line IV-IV of FIG. 3;

[0038] FIG. 5 is a section view of the sheet of FIGS. from 2 to 4 during a first production step of the wrapper of FIG. 1;

[0039] FIG. 6 is a lateral view of the sheet of FIGS. from 2 to 4 during a second production step of the wrapper of FIG. 1; and

[0040] FIG. 7 is a section view of a second embodiment of the sheet for producing the wrapper of FIG. 1.

[0041] To facilitate comprehension, the same reference numbers have been used, where possible, to identify identical common elements in the drawings. It is understood that elements and characteristics of one embodiment can conveniently be incorporated into other embodiments without further clarifications.

DETAILED DESCRIPTION OF SOME EMBODIMENTS

[0042] We will now refer in detail to the possible embodiments of the invention, of which one or more examples are shown in the attached drawings. Each example is supplied by way of illustration of the invention and shall not be understood as a limitation thereof. For example, one or more of the characteristics shown or described insomuch as they are part of one embodiment can be varied or adopted on, or in association with, other embodiments to produce further embodiments. It is understood that the present invention shall include all such modifications and variants.

[0043] Before describing these embodiments, we must also clarify that the present description is not limited in its application to details of the construction and disposition of the components as described in the following description using the attached drawings. The present description can provide other embodiments and can be obtained or executed in various other ways. We must also clarify that the phraseology and terminology used here is for the purposes of description only, and cannot be considered as limitative.

[0044] Embodiments described here concern a packaging wrapper for baking gluten-free food products, generally frozen, in an oven, without gluten contamination and maintaining crunchiness. The embodiments described here generally provide that the wrapper comprises a layer of filter material coupled, by means of adhesive, to a layer of polymeric material, the whole being resistant to a temperature of at least 200° C., possibly even up to 220° C.

[0045] With reference to FIG. 1, this shows a first embodiment of the packaging wrapper 10 for allergen-free food products, even more particularly for gluten-free food products, such as bread or other baked products made from leavened dough, savory or sweet, such as pizza, focaccia, crackers, breadsticks, sweet and/or savory snacks or suchlike, offered in large-scale distribution. The packaging wrapper 10 can also be used with raw products made from leavened dough, to be cooked after purchase.

[0046] In FIG. 1, the wrapper is represented in its finished form, that is, shaped, sealed and containing a food product 20 such as bread or other product made from leavened dough and without gluten in it.

[0047] The wrapper 10 is made by means of a multilayer sheet 11 that comprises a layer of polymeric material 12 and at least one layer of filter material 13 coupled to it (see also FIGS. 2 and 3).

[0048] The layer of polymeric material 12, which is airtight, has at least one shaped aperture 14, for example two apertures 14 with an elliptical shape. Clearly, the number, shape and sizes of such apertures can vary according to requirements.

[0049] The filter material 13, also known as filter paper, is coupled to the polymeric material 12 so as to completely cover the apertures 14. In the example shown, the sheet 11 comprises two layers of filter material 13, each coupled in correspondence with a different zone, so as to each cover two respective apertures 14. It is noted that the two layers of filter material 13 are coupled on a same surface of the layer of polymeric material 12 (FIG. 4).

[0050] The sheet 11 as shown in FIGS. 2 and 3 is substantially rectangular in shape and is delimited by two reciprocally opposite transverse edges 11A, disposed horizontally in FIGS. 2 and 3, and two longitudinal edges 11B reciprocally opposite each other and inclined, preferably perpendicular, with respect to the two transverse edges 11A. The transverse 11A and longitudinal edges 11B are designated relative to the direction of feed of the sheet 11 during the production of the wrapper 10, said direction being represented by the arrow in FIG. 2.

[0051] Each layer of filter material 13 is preferably rectangular in shape and advantageously covers the layer of polymeric material 12 from one transverse edge 11A to the other, but not from one longitudinal edge 11B to the other. It is in fact advisable to provide that the layers of filter material 13 have a smaller width than the distance between the two longitudinal edges 11B and that they be disposed so as to leave uncovered at least two longitudinal flaps 12A of polymeric material 12 located along a respective longitudinal edge 11B of the sheet 11.

[0052] The two layers of filter material 13 are also distanced from each other so as to define an uncovered intermediate zone 12B of the polymer layer. This uncovered intermediate zone 12B is preferably located substantially centrally with respect to the longitudinal edges 11B of the sheet 11, so that when the wrapper is formed said intermediate zone 12B is in a substantially central position on one side of the wrapper 10 (FIG. 1).

[0053] It should be noted that, obviously, the layers of filter material 13 can have different shapes and sizes, for example they can be such as to cover only one respective aperture 14 and one zone adjacent thereto, without necessarily extending from one transverse edge 11A of the sheet 11 to the other. In this way, it is also possible to delimit two transverse flaps of polymeric material 12, not shown in the drawings.

[0054] The layer of polymeric material 12 is preferably transparent, so that the food product 20 can be seen inside the wrapper 10 when it is closed. The polymeric material consists of one or more layers of PET, PA, cast PP or coextruded PP. Preferably, the polymeric material comprises PET with a Mylar coating. Generally, the layer of polymeric material 12 is punched.

[0055] The filter material 13 preferably comprises at least 80% by weight of a fibrous material, in particular natural fibers, more particularly cellulose. The basis weight of the filter material 13 is between 30 and 90 g/m.sup.2, preferably between 40 and 70 g/m.sup.2, even more preferably between 48 and 51 g/m.sup.2. The layer of filter material 13 preferably has a thickness between 50 and 200 μm, more preferably between 60 and 100 μm, even more preferably substantially equal to 85 μm. The layer of filter material 13 can have different conformations and mechanical strengths according to the conformation which it is to be given, for example a smooth, rough or crinkled conformation. Amongst these, the rough conformation and the crinkled conformation are preferred, since they provide a greater filtration area and offer high filtration speeds. The crinkled conformation also offers a higher capacity to retain particulates than smooth paper.

[0056] The filter material 13 may also comprise other natural fibers, for example alpaca fibers, and/or artificial fibers, such as rayon fibers.

[0057] The filter material 13 is of the porous type, and has pores, that is, apertures, the size of which is preferably less than 150 μm; more preferably equal to 100 μm or less, even more preferably between 1 and 100 μm.

[0058] The filter material consists of a plurality of overlapping fibrous layers. A filter with this particular configuration is such as to prevent the passage of allergens, including gluten in particular, as well as microbiological contamination.

[0059] The filter material has a permeability to air such that water vapor is allowed to pass, which determines the crunchiness of the food product.

[0060] The porosity of the filter material 13 is such as to prevent the passage of allergens, including gluten in particular, as well as microbiological contamination.

[0061] The layers of filter material 13 are coupled to the layer of polymeric material 12, preferably by means of gluing using one or more layers of adhesive 15 (FIG. 4). The layers of adhesive 15 are located at least along the edges of the apertures 14 of the polymeric material 12, but preferably the adhesive 15 is applied over the entire surface where the layer of polymeric material 12 and the layer of filter material 13 overlap.

[0062] The adhesive advantageously consists of a dispersion in a water-based solvent, alcohol, a single-component polyester-based adhesive or a bio-component adhesive with polyester and reagent.

[0063] Favorably, the layer of filter material 13 is glued to the external surface of the polymeric material 12 so as to suitably cover the aperture 14, or the apertures 14 if more than one. The external surface of the polymeric material 12 is the surface of the polymeric material 12 opposite the internal surface of the polymeric material 12 normally in contact with the food product, that is, the external surface, in normal use, is not facing toward the food product present in the wrapper 10.

[0064] Preferably, the layer of filter material 13 is glued on to the external surface of the polymeric material 12 and only along the perimeter edge of the aperture 14, or the apertures 14 if more than one, so as to overlap with the polymeric material 12 only as much as is necessary to be able cover the respective aperture 14 from the outside.

[0065] The polymeric material 12, the filter material 13 and the adhesive 15 are resistant both to sudden changes in temperature from −30° C. to 250° C., and also to high temperatures, that is, the temperatures commonly used to bake bread in an oven, typically for an interval of time from 0 to 2 minutes, in particular from 0 to 30 seconds. Typically, these temperatures are higher than 150° C., more particularly higher than 200° C., for example they can reach 220° C., for a period of time between 5 and 30 minutes, preferably between 10 and 20 minutes. This resistance to heat can be obtained by means of a chemical treatment of a type known in the field. It is advisable to carry out a treatment to cross-link the polymeric structure of the cellulose.

[0066] The wrapper 10 is preferably made starting from a sheet 11 as shown in FIGS. 2 and 3, by means of a flow pack type process, widely known in the field.

[0067] FIGS. 5 and 6 show two steps of this process. It is noted that in FIGS. 5 and 6 the wrapper 10 is made with the filter material 13 disposed on the external surface. It is obviously possible to provide that the filter material 13 is disposed inside the wrapper 10.

[0068] Thanks to the polymeric material 12 and the filter material 13, the wrapper 10 effectively prevents the passage of allergens, in particular gluten, from the outside to its inside. It therefore becomes possible to freeze and cook the food product in industrial equipment (freezers, ovens) without the risk of contamination. It can also be provided to display the gluten-free food product at the point of sale next to other food products of the same type.

[0069] Moreover, thanks to the particular configuration of the filter material 13, the steam that develops inside the wrapper while the food product is cooked flows out of the wrapper 10. The organoleptic properties of the food product 20, in particular its crunchiness, in the case of freshly baked gluten-free bread, are preserved for a predetermined period of time starting from the cooking of the product.

[0070] FIG. 7 shows a second embodiment of the multilayer sheet 11. In this second embodiment, the layers of filter material 13 are disposed between two overlapping layers of polymeric material 12. Both layers of polymeric material 12 are provided with respective apertures 14, overlapping each other and therefore entirely covered by a respective layer of filter material 13. Providing two layers of polymeric material 12, between which the filter material 13 is interposed, allows to have a sheet 11 that is stronger and more resistant to sudden changes in temperature.

[0071] The adhesive 15 is applied in the contact zones between polymeric material 12 and filter material 13, in particular around the apertures 14, preferably also in the contact zones between the two layers of polymeric material 12, for example in correspondence with the longitudinal flaps 12A and with the intermediate zone 12B between the two layers of filter material 13.

EXPERIMENTAL DATA

[0072] We have analyzed the crunchiness of a gluten-free bread baked in a wrapper 10 specimen as described above.

[0073] The analysis was performed by means of a TA-AT2i texture analyzer with a P75 flat type probe, in order to have a greater contact surface on the bread crust.

[0074] The analysis graph contains the time in seconds on the x-axis and the force expressed in grams on the y-axis. During the analysis, the probe compresses the bread, and this increases the force. If the bread is crunchy, the compression causes cracks on the external surface. The slight change in force during these breakages creates typical spikes on the graph's force line. The linear distance is the function that calculates the length of an imaginary line that joins all the points on the graph comprised between the point in which the force curve begins (that is, when the probe touches and begins to compress the sample) and the point in which the experiment ends (generally after about 5 seconds). The more peaks are present, the greater the crunchiness and the greater the numerical value of the linear distance.

[0075] The parameters measured and taken into account in the evaluation of crunchiness are therefore: [0076] the force, expressed in grams, intended as the maximum force to compress the sample; [0077] the linear distance joining all the points in the selected region from zero to about 5 seconds. This quantity, expressed by the above function, has arbitrary units of measurement.

Example 1—Crunchiness Analysis 30 Minutes after the Loaves were Removed from the Oven

[0078] The analysis was performed 30 minutes after 8 loaves were removed from the oven, each baked in a respective wrapper according to the invention. More precisely, the procedure provides to place the 8 frozen gluten-free bread samples, each wrapped in a respective wrapper as described here, in the oven at 200° C. for 10 minutes, to remove them and let them cool down at room temperature for 30 minutes. Then the wrapper is removed and the whole loaf of bread is positioned under the probe of the texture analyzer. The operation was repeated for all 8 bread samples made. The samples have an average force of 4900 g and an average linear distance of 57.

[0079] These values, however, are in line with the analysis by texture analyzer of a fresh loaf of wheat bread analyzed a few hours after purchase, having an average force of 4500 g and an average linear distance of 49. These values differ greatly from those obtained from the analysis by texture analyzer of a loaf of bread packaged in modified atmosphere which has an average force of 1800 g and a linear distance of 19. The following Table 1 reports the results obtained for gluten-free frozen bread packaged with a wrapper described here, bread packaged in modified atmosphere and fresh wheat bread.

TABLE-US-00001 TABLE 1 Linear Sample Force (g) distance Gluten-free bread packaged frozen with a wrapper 4900 57 described here Bread packaged in modified atmosphere 1830 19 Fresh wheat bread 4547 49

[0080] The optimal crunchiness values or parameters correspond to a force between 2500 and 6000 g, a linear distance between 25 and 90. The values obtained during the tests are all within these limits.

Example 2—Analysis 30 Minutes and 1, 2 and 4 Hours after the Loaves were Removed from the Oven

[0081] A subsequent analysis was performed 30 minutes, 1 hour, 2 hours, 3 hours and 4 hours after 16 loaves were removed from the oven, each baked in a respective wrapper according to the present description and following the procedure identified here, and the results were compared with 16 loaves each baked in their currently existing wrapper.

[0082] Table 2 below reports the results obtained for force (g) for samples packaged with an existing wrapper and samples packaged with a wrapper described here, while Table 3 reports the results obtained for linear distance for samples packaged with an existing wrapper and samples packaged with a wrapper described here.

TABLE-US-00002 TABLE 2 Force (g) 30 min 60 min 120 min 180 min 240 min Samples packaged 1681.627 2082.248 1444.713 na na with an existing wrapper Samples packaged 2252.612 2535.564 2249.285 1852.513 1594.87 with a wrapper described here

TABLE-US-00003 TABLE 3 Linear distance 30 min 60 min 120 min 180 min 240 min Samples packaged 19.237 22.843 17.453 na na with an existing wrapper Samples packaged 25.433 27.037 24.239 20.81 18.406 with a wrapper described here

[0083] The data show that the bread packaged with the wrapper described here has a greater force and linear distance than the existing wrapper, if analyzed after 30 minutes, but also after 1, 2 and 3 hours. Only after 4 hours does the bread packaged with the wrapper described here reach an average force and a linear distance similar to that of the bread packaged with the currently existing wrapper and analyzed after 30 minutes, that is, an average force of 1600 g and an average linear distance of 19.

[0084] Further embodiments concern a packaging comprising at least one gluten-free food product packaged in a packaging wrapper 10 as described here. Favorably, the gluten-free food product has the following crunchiness parameters: force between 2500 and 6000 g, linear distance between 25 and 90. The gluten-free food product as above can be packaged in wrapper 10 in frozen form. Typically, the frozen product, packaged in the wrapper 10, can then be subjected to cooking in an oven. Therefore, it can also be provided, according to this description, that the packaging comprises the wrapper 10 in which the gluten-free food product cooked in the oven is present.

[0085] It is clear that modifications and/or additions of parts may be made to the packaging wrapper for food products as described heretofore, without departing from the field and scope of the present invention, as defined by the claims.

[0086] It is also clear that, although the present invention has been described with reference to some specific examples, a person of skill in the art shall certainly be able to achieve many other equivalent forms of packaging wrapper for food products, having the characteristics as set forth in the claims and hence all coming within the field of protection defined thereby.

[0087] In the following claims, the sole purpose of the references in brackets is to facilitate reading: they must not be considered as restrictive factors with regard to the field of protection claimed in the specific claims.