Note: Descriptions are shown in the official language in which they were submitted.
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
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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-
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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,
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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
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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 : -
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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
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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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