CA1143928A - Display package for food products - Google Patents

Abstract

DISPLAY PACKAGE FOR FOOD PRODUCTS

Abstract of the Disclosure A package for containing and dis-playing food products which tend to exude juices or fluids, and which comprises a support tray and an absorbent pad positioned therein. The absorbent pad comprises a mat of liquid absorbent material, an upper liquid impermeable sheet overlying the absorbent mat, and a perforated bottom sheet underlying the absorbent mat. When a food product is positioned upon the absorbent pad, any exuded fluids will enter the mat by capillary action through the perforated openings of the bottom sheet, and the fluids will be held out of contact with the food product to thereby minimize contamination of the product and maintain its appearance and improve its shelf-life. The pad also has independent utility as a moisturizing device for use in closed food containers or packages.

Description

DISPLAY PACKAGE FOR FOOD PRODUCTS
The present invention relates to an improved display package of the type used to display various food products, and which acts to substantially improve the appearance and shelf~life of the product.
It is conventional practlce to display meat, poultry, and other food products in individual packages which comprise a supporting tray with an absorbent pad of tissue-like paper wadding in the bottom of the tray to absorb any juices or fluids exuded from the food 10 product~ A transparent outer plastic wrapping is also usually employed to cover and surround the package.
A major problem associated with such packages is the fact that the exuded juices support thls rapid growth of bac-teria, which migrate back to the food product and result 15 in spoilage and discoloration thereof. As will be apparent, such spoilage and discoloration quickly renders the food product unsuitable for sale.
In an effort to alleviate the above problem, and to extend the shelf-life of such food products, it has 20 been proposed ~o employ an absorbent pad in the package ~hich includes an i~perforaLe plastic film positioned above the absorptive wadding, and such that the plastic ilm acts to retard the reverse migration of the juices back to the food product. Also, it has been proposed to

2$ position a non-absorptive barrier above the absorbent material for this purpose, note the U. S. Patent to Niblack et al No. 3,026,209. While the above package constructions provide a spacial relation~hip between the exuded juices in the pad and the food product, they -f~

nevertheless permit the substantial migration of bacteria back to the food pro- -duct and thus are not totally satisfactory.
It is accordingly an object of the present invention to provide a display package for food products which substantially alleviates the problem of food spoilage and discoloration resulting from bacterial growth within the exuded juices, and thus materially contributes to the shelf-life of the food product.
The invention provides a receptacle for containing and displaying food products which tend to exude liquids, such as meat and poultry, and characterized by the ability to separate and maintain the exuded liquids from the food product to thereby minimize contamination of the food product and improve the appearance and shelf-life thereof, and comprising a food product supporting member having a wall, and an absorbent pad overlying and resting upon said wall, said pad com~
prising a mat of liquid absorbent material, and imperforate, liquid impermeable upper sheet overlying and covering said mat, and a bottom sheet of substantially :~
liquid impermeable material underlying said mat so as to be disposed between said mat and said supporting member wall, the. peripheral edges of said upper and bottom sheets being sealed together to enclose said mat of absorbent material therebetween, and said bottom sheet including a plurality of openings which are ~ :
sized to permit passage of a liquid from said supporting member wall into said mat while substantially precluding reverse flow of the liquid and any associated bacteria back to the food product, and such that the liquid passes around the edges of the pad and into said mat and is confined by said pad out of contact with the food product.
The receptacle may comprise a relatively rigid tray. The receptacle or display package is aesthetically pleasing, is able to hold and retain a sub-stantial quantity of fluid, and permits the use of chemical additives in the ;~
absorptive material while preventing the additives from contacting the food pro-` 2 .'.~; ' `I ~

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duct.
In a preferred embodiment, the liquid absorbent material is composed of superposed layers of hydrophilic cellulose base fibers, with the layers being mechanically interconnected to main-tain the relative positioning thereof. The upper and lower sheets comprise a plastic film material, with the peripheral edges being heat sealed together to enclose the absorbent material.
Some of the objects having been stated, other objects will appear as the description proceeds, when taken in connection with the accompanying drawings, r ~3 ` -'~

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in which ~
Figure l is an exploded perspective view of a display package for~food products which embodies the features of the present invention;
Figure 2 is a perspective view of the absorbent pad of the present~
invention;
Figure 3 is an enlarged, fragmentary perspective view of the bottom sheet of the pad;
Figure 4 is an enlarged, fragmentary sectional elevation view of~the~
pad and taken substantially along the line 4-4 of Figure 2; and Figure S is an enlarged, fragmentary sectional elevation view showing~
the openings in the bottom sheet and taken substantially along the line 5-5~of Figure 3.
Referring more specifically to the drawings, Figure 1 discloses a~
display package or receptacle which embodies the present invention, and whlch~
comprises a support tray 10, and an absorbent pad 12. The support tray 10 may~

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conveniently be fabricated from a molded foam plastic material, and includes a generally rectangular bottom wall 14 and an upstanding peripheral side wall~l5.
The absorbent pad 12 is also rectangular, and is sized to overlie substantially~
the full area of the bottom wall 14 of the tray. In use, the pad 12 is -3a-J

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positioned upon the bottom ~lall 14, and the food product ::
is positioned to rest upon the pad. Further, an outer wrapping of suitable thermoplastic film material (not shown) may be positioned over the food product and heat ::~
5 sealed bzneath the tray 10 in the conventional manner. :
The pad 12 comprises a mat 16 of liquid absorbent material, an upper sheet 18 o~ substant;ally liquid . . :
impermeable hydropho~ic material overlying and covering the mat of absorbent material, and a bottom sheet 19 : ~ .
of hydrophobic material underlying the mat of absorbent material so as to be d~sposed between the mat and the : -tray bottom wall 14.
The thickness of the mat 16 may be varied to control the absorbency therebf, and typically is between:
15 about 1/8 to 1/4 inch.es so as to permit absorption and ~ :
retention of a substantial quantity of liquid. The ~ : :
mat may be composed of a num~er of abrorbent materials, : :~ :
such as stacked layers of tissue~like paper wadding, a mat of conventional de~iberized wood pulp (known in the :~
art as wood fluff~, a mat of synthetic pulp such as rayon,~
a mat of cotton, or comb~nations of the above. .
In the preferred em~odiment as illustrated herein,~
the mat 16 is composea of hydrophilic cellulose base :~
fibers~ and m~re particularl~, the mat is compose~ of a relatively thick layer of wood fluff 20, and a relative~
ly thin layer of tissue-like paper wadding 21 ~ood :~
fluff is well known in th.e art and consists of~defiberized~
cellulose fibers which have been formed into a compressed batt in the manner of a non-woven fabric. The fluff la~er has little or no consistency or integrity, and it is thus difficult to maintain in web form during manu~
facturing operations The paper wadding 21, which is also known in the art, is produced on a Fourdr~ni.er paper making machine~ and may, if des;red, ~e creped : -~
3s fox added body. T~e wadding typically has a textures;milar to househbld facial tissue, and has substantially more integrity than doea thè wood flu~f.

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The layers of wadd~ng and wood fluff are super-posed and mechanically interconnected by the diamond-shaped embossing 22 to maintain the relative positioning thereof and the integrity of the wood fluff, and to facilitate handling of t~e fluff during the manufacturing operations. The embbssing 22 typically comprises myriad distinct indentations along the lines of the diamond-shaped pattern and wh:ich serve to compact and thereby interconnect the superposed layers along those lines~
Such embossing ma~ ~e imparted to the mat by passing the superposed layers th.rough conventional embossing rolls (not shown). As best seen in Figure 4, the wadding layer 21 is preferably disposed immediately adjacent .
the perforated bottom sheet lq as hereinafter further descri.~ed,and in thi~ orientation, it has been found lS that the wadding layer also acts to prevent any loose fluff dust from passing through. thè openings and possibly contaminating the food product.
Various additives ma~ be added to the mat to increase its liquid absorbency~ A particular example o~ a suita~le additive of this type is a synthesized .:
starch, such as th.e starch-acrylonitrile graft co~polymer as described inU. S. Patent No~ 3,661,815. This product is marketed commercially as a ~ree flowing po~der, which may be either sifted onto th.e 1uff layer or ;
sift2d into the flu~ chamber when the layer is being - formed. In addition, a Bactexicidal agent, such. as po~assium sorbate, may be added to the mat to retard bacterial growth~ :
The upper and lower sheets 18 and 19 are 3n typically of like construction and are composed of a ~:
material which is non-reactive to food products~ For example, the sheets may comprise a thermoplastic film, such as polyethylene having a thic~ness between about .00035 to .005 inches~ The peripheral edges of the upper and bottom sheets are preferably sealably secured together as shown at 23 by any suitable means, suc~ as . ~ .

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a hot melt adhesive'seal~ ox b~ heat sealing r to thexeby sealably enclose the mat of absorbent material there-between. In addition, the bottom sheet 19 includes a plurality of minute openings 24 which permit the ' 5 passage of a liquid from the tray bottom wall into the ~ ~ ;
absorbent material. The openings 24 are distributed ' substantially uniformly over the full area of the sheet and typically have a density of between about 15 and ~ ;~
100 per square inch,' and pre~erably between between 10 about 80 to 90 per square inch.' In this regard, the ;~
openings 24 may be'formed by a perforating operation, such~
such'as by contacting the film with'a roll covered with pins having a diameter of about .01 inches, and of the type used on a text~le'carding cloth. Such perforating operation results in the openings having a diameter of about .01 inches~ and peripheral portions 25 (note Figure 5~ which extend out~ardly from the sheet. Also, the sheet is oriented so that the peripheral portions 25 extend toward the mat 16 and thereby act to further retard the passage'of liquid outwardly from the mat and through the sheet.
In use, the'juices from the food product resting~
on t~e pad 12 will tend to flo~ downwardly onto the bottom~
wall 14 of the tray and beneath the pad~ The capillary action of the absorbent material in the mat 16 tends to lift these juices into the pad where they are held out of `~
contact with the food products.- The upper sheet 18 ;~
prevents these absorbed juices and any additives in the~
mat from directly contacting t~e food product, and the~
3Q combin~tion of'the capillary action and the small size Rnd construction of the openings 24 acts to retard the reverse flow of the liquids through the openings. Thus substantially all migration of the exuded juice5 back to the food products is precluded, thereby significantly alleviating the problems of spoilage and discoloration.
Further, the upper suxface of the sheet 18 remains relatively clean and smooth'in use thereby resulting . .

~ 7- ' in an aesthetical]y pleasin~ appearance.
It has also been found that the pad 12 has separate utility as a hydrating or moisturizing dev;ce, whereby moisture may ~e provided to various food pro~
ducts, such as lettuce or mushrooms, while stored in a closed container or package. In particular, the pad may be thoroughIy saturated by dipping in water, and then placed in the food container or package~ The water in ~-the pad will slowly vaporiæe, and pass outwardly through 10 the openings 24 to there~y maintain a relative high ~' humidity level withi'n the container or package.
In the drawings and specification, there has been set ~orth'a preferred embodiment of the invention, and although'specific terms are employed, they are used in a generic and descriptive sense only and not for pur~
poses of limitation.
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Claims (15)

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. A receptacle for containing and displaying food products which tend to exude liquids, such as meat and poultry, and characterized by the ability to separate and maintain the exuded liquids from the food product to thereby minimize contamination of the food product and improve the appearance and shelf-life thereof, and comprising a food product supporting member having a wall, and an absorbent pad overlying and resting upon said wall, said pad compris-ing a mat of liquid absorbent material, and imperforate, liquid impermeable upper sheet overlying and covering said mat, and a bottom sheet of substantially liquid impermeable material underlying said mat so as to be disposed between said mat and said supporting member wall, the peripheral edges of said upper and bottom sheets being sealed together to enclose said mat of absorbent material there-between, and said bottom sheet including a plurality of openings which are sized to permit passage of a liquid from said supporting member wall into said mat ;
while substantially precluding reverse flow of the liquid and any associated bacteria back to the food product, and such that the liquid passes around the edges of the pad and into said mat and is confined by said pad out of contact with the food product.

2. The receptacle as defined in Claim 1 wherein said upper and bottom sheets each comprise a flexible plastic sheet material, and said openings are distributed substantially uniformly over the full area of said bottom sheet.

3. The receptacle as defined in Claim 2 wherein said mat of liquid absorbent material comprises superposed layers of paper wadding and wood fluff.

4. The receptacle as defined in Claim 3 wherein said openings include peripheral portions which are inclined outwardly from said bottom sheet and toward said mat, to thereby further retard the reverse flow of liquids outwardly from the mat and through the bottom sheet.

5. The receptacle as defined in Claim 1, 2 or 3 wherein said supporting member comprises a relatively rigid tray.

6. A receptacle for containing and displaying food products which tend to exude liquids, such as meat and poultry, and characterized by the ability to separate and maintain the exuded liquids from the food product to thereby minimize contamination of the food product and improve the appearance and shelf-life thereof, and comprising a supporting tray having a bottom wall, and an absorbent pad overlying and resting upon said bottom wall, said pad comprising a mat of liquid absorbent material, an imperforate, liquid impermeable upper sheet overlying and covering said mat, and a bottom sheet of substantially liquid impermeable material underlying said mat so as to be disposed between said mat and said tray bottom wall, the peripheral edges of said upper and bottom sheets being sealed together to enclose said mat of absorbent material there-between, and said bottom sheet including a plurality of openings which are sized to permit passage of a liquid from said tray bottom wall into said mat while substantially precluding reverse flow of the liquid and any associated bacteria back to the food product, and such that the liquid passes around the edges of the pad and into said mat and is confined by said pad out of contact with the food product.

7. The receptacle as defined in Claim 6 wherein said bottom wall of said supporting tray is of rectangular outline and includes an upstanding peripheral wall, and said absorbent pad has a rectangular outline generally conforming to that of said bottom wall so as to substantially fully cover said bottom wall.

8. The receptacle as defined in Claim 7 wherein said upper and bottom sheets of said pad each comprise a thermoplastic film, and the peripheral edges thereof are sealably secured together by means of a hot melt adhesive.

9. The receptacle as defined in Claim 8 wherein said mat of liquid absorbent material comprises superposed layers of paper wadding and wood fluff which are mechanically interconnected to maintain the relative positioning thereof, and wherein the layer of paper wadding is disposed immediately adjacent said bottom sheet.

10. The receptacle as defined in Claim 9 wherein said openings are distri-buted substantially uniformly over the full area of said bottom sheet.

11. The receptacle as defined in Claim 10 wherein said openings have a diameter of about .01 inches and a density of between about 15 and 100 per square inch.

12. The receptacle as defined in either Claim 1 or 6 wherein said mat of liquid absorbent material is essentially cellulosic.

13. The receptacle as defined in either Claim 1 or Claim 6 wherein said mat of liquid absorbent material is essentially cellulosic and includes a liquid absorbing synthesized starch.

14. The receptacle as defined in either Claim 1 or Claim 6 wherein said mat of liquid absorbent material is essentially cellulosic and includes a bacteriostatic agent.

15. The receptacle as defined in either Claim 1 or 6 wherein said mat of liquid absorbent material comprises a layer of paper wadding and a layer of wood fluff, and with the layer of paper wadding being positioned immediately adjacent said bottom sheet whereby the paper wadding acts to prevent dust from said wood fluff from passing outwardly through said openings.