Note: Descriptions are shown in the official language in which they were submitted.
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CONTROLLED ATMOSPHERE PACKAGE FOR BANANAS
Field of the Invention
[0001] The invention relates to the field of packaging fruits and
vegetables and, in particular, to designs of controlled atmosphere banana
packages.
Background of the Invention
[0002] During the processes of storing and transporting bananas,
starting from harvest, going through delivery into the distribution network,
and finally until the bananas are brought directly to the consumer, it is
necessary to ensure certain storage conditions.
[0003] The storage conditions can be characterized by defined
temperature, moisture, and gas medium composition surrounding the
bananas. If the storage conditions are not adhered to, the bananas will not be
delivered to the consumer in the required condition, for example, in terms of
ripeness of the product, and will even spoil. In particular, during transport
and
storage the bananas are packaged into boxes as clusters in their green, non-
ripe condition. These boxes are assembled in stacks and are placed into big
transportation containers. During the process of loading and transport, a
temperature between 56 - 59 F is maintained. At such temperatures, the
bananas can be stored for a long time.
[0004] To start the ripening process, the temperature must be increased
to 60 - 62 F and the gas composition surrounding the bananas must be
modified by adding ethylene to it. The combination of ethylene and increased
temperature helps to start the ripening process.
[0005] Further on, when the bananas are delivered to the distribution
network, they should not ripen too quickly, should not spoil, should preserve
good market condition, and the buyer should be able to view the bananas.
Such requirements lead to the necessity to create special packages, which
provide for both the change in the gas medium composition surrounding
packaged bananas and the preservation of their market condition.
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[0006] Inventions are known in the art that are related to
transportation and storage of bananas, and which address the indicated
tasks of packaging, transportation, and storage.
[0007] In EPO Published Application EP 752378, "Controlled
atmosphere package for fruit and packaging method", published June 13,
2001, a packaging for fruits, in particular, for bananas, is described that
includes no less than one hermetically sealed bag with at least one unripe
fruit placed inside it; the bag being made of a polymer film material, the
thickness of which is 20 - 50 pm and is filled with a modified atmosphere. The
polymer material can be low-density polyethylene, polyethylene, high-density
polyethylene, polypropylene, polyethylene terephthalate, and other materials.
The modified atmosphere includes from 2 - 20% oxygen (vol.), from 6-13%
carbon dioxide (vol.), and from 0.1 - 1.5 % ethylene (vol.), with the
remainder
being nitrogen.
[0008] In US Patent 6,013,293, "Packing respiring biological materials
with atmosphere control member", De Moor, issued January 11, 2000, a
package is described that ensures the necessary gas composition in storage
of fruits and vegetables, as well as other respiring biological materials. A
selective gas-permeable membrane, which is a part of this package, conducts
oxygen at a lower rate than other gases, in particular, carbon dioxide and
ethylene. Using such a membrane in banana storage is said to ensure optimal
conditions of banana ripening.
[0009] In US Patent 6,548,132, "Packaging biological materials", Clarke
et al., issued April 15, 2003, a package is described that includes a sealed
container, respiring biological material, and a gas medium inside the
container. The container has walls that are relatively impermeable to oxygen
and carbon dioxide, and is equipped with an atmosphere-control element
inside the container. The control element includes a gas-permeable
membrane, consisting of a micro-porous film in the form of a polymer matrix,
having a network of gas-impermeable pores and a polymer coating applied
over the film. The package is said to ensure the generation of a gas medium
inside the container which is favorable for storing respiring biological
materials.
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Summary of the Invention
[00010] The invention herein provides for the long term storage of
bananas prepared for sale utilizing a modified gas medium composition,
is easy to manufacture, convenient to use, and ensures a good packing
factor for the bananas. The packaging enhances the freshness of the
bananas whether they are stored at the warehouse, grocery store, or on a
consumer's kitchen counter. Also, at the grocery store, this packaging
provides display of bananas, so that consumers can select them.
[00011] The controlled atmosphere package for bananas includes a
container with an atmosphere control element. In use, bananas, usually no
less than two bananas, are placed inside the container. The container has
walls and a bottom, the upper part of the container is sealed with a polymer
film. One of the container walls is embodied in such a way that it has a
convex side which is turned outwards. An atmosphere control element is
placed near the wall of the container which is opposite to the convex wall,
and
is embodied as a hole in the container bottom. A selective gas permeable
membrane is secured to the container bottom in such a way that a hermetic
seal covers the holes by said membrane. The bananas are placed closely
together with their convex side facing the convex wall of the container.
[00012] The packaging herein claimed enables packing bananas in
the container in a row, fairly densely, without significant gaps. The
packaging also provides the necessary gas medium composition near each
banana, since it is equipped with an atmosphere control element that is
located near the wall, opposite to the convex side of the container. Due to
the packaging design and
[00013] the positioning of the atmosphere control element near the
container wall, the body of the banana, which is located near the wall in a
fixed position, does not obstruct the atmosphere control element since the
banana has a curved shape. Polymer film that covers the roof of the
container leaves gaps between the bananas. Through these gaps, the gas
medium inside the container comes into contact with the atmosphere control
element and interacts with the surface of each banana.
[00014] To achieve the non-compressibility of packaging, the walls and
the bottom of the container could be embodied as rigid. The walls and/or
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bottom of container could also be embodied as transparent to allow the
consumer to view the bananas.
[00015] The upper part of the container walls can be equipped with
collars that are convenient to attach to the polymer film, thus ensuring the
package is sealed.
[00016] To achieve a convenient arrangement of several packages in a
stack, convex areas facing outwards could be created in the corners of the
container bottom. The convex areas of the package create a gap between
packages when they are stacked. This allows air to reach the atmosphere
control element in the bottom of container.
[00017] The selective gas-permeable membrane could be attached to
the container bottom from the inside. In this case, better protection of the
membrane is provided for. During storage when several packages are
arranged in a stack, this membrane position insures free access of outside air
to the membrane due to the presence of gap between containers created by
said convex areas.
[00018] The selective gas-permeable membrane could be attached to
the container bottom in such a way that the area of generated membrane
parts, which are not attached to the container bottom, will be greater than
the
area of the said holes. The membrane can also be attached to the container
bottom along its perimeter, so that an area of the middle part of the
membrane, which is not attached to the bottom, will be greater than the area
of the said holes.
[00019] To provide for the required gas atmosphere inside the package,
which is preconditioned by the ratio of oxygen content to the content of C02,
the area of the part of the gas-permeable membrane that stays in contact with
the atmosphere should be definite, depending upon the container dimensions.
However, it is not always feasible to make the size of the holes in the
container equal to the necessary area of the membrane because the larger
the holes, the greater the risk of damaging the membrane during packaging.
Therefore, it is suggested to make the hole area less than the area of the
parts of the membrane that are not attached to the container bottom, because
during the gas exchange process, pressure inside the package is less than
the atmospheric pressure and part or parts of the membrane that are not
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attached to the bottom will be pushed inside the container (in a concave
manner) and will efficiently operate during the process of gas exchange.
[00020] The container bottom, where the holes of the atmosphere
control element are located, can be convex. This embodiment solves the
following problems:
= there is decreased risk of damaging the gas-permeable
membrane, since the holes for the atmosphere control
element are raised above the plane of the package bottom;
and
= there is no need to introduce additional convex areas to
ensure air accesses the holes of the atmosphere control
element.
[00021] Bananas of roughly equal degree of curvature can be placed
inside the container, to ensure the highest packing factor.
[00022] If there is a need to place bananas of different curvature inside
the container, a banana with a lesser curvature should be placed near the
convex wall, which prevents the atmosphere control element from being
covered by the body of the banana.
[00023] When bananas of different curvature degree are placed inside
the container, bananas could be arranged in an order, which implies that the
degree of curvature increases with the increase of the distance between the
banana and the convex wall of the container. Such arrangement of the
bananas also prevents the atmosphere control element from being covered
by the body of banana.
Brief Description of the Drawings
[00024] The invention is illustrated with the following drawings.
[00025] In Fig. 1 the general view of the package is presented as seen
from above, in Fig. 2 - as seen from above, with bananas inside. Fig. 3
presents a lateral cross-section view of the package and Fig. 5 presents the
package as seen from below. Fig. 4 presents the cross-section of the
package near the collar.
[00026] Fig. 6 and Fig. 7 show fragments of the container bottom from
above with different options for the embodiment of the atmosphere control
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element. Fig. 8 and Fig. 9 present cross-sections of the container bottom
with different options for the embodiment of the atmosphere control
element.
[00027] Fig. 10 shows an option of embodying the package with a
convex section of the container bottom where the holes of the atmosphere
control element are located - view from above. Fig. 11 shows the lateral view
of the same option. Fig. 12 shows another option of embodying a convex
area of the container bottom where the atmosphere control element is
located - view from above.
[00028] Fig. 13 presents the cross-section of the container bottom.
Detailed Description of the Invention
[00029] Banana packaging with a controlled atmosphere (Fig. 1 - Fig. 3,
Fig. 5) includes a container (1) with an atmosphere control element (2) and
bananas (3) placed inside the container (1). The container (1) has walls (4)
with collars (5) and a bottom (6). From above, the container (1) with bananas
(3) is closed with a polymer film (7) that is hermetically secured on the
collars
(5). One of the walls (8) has an outward convex shape. The atmosphere
control element (2) is placed near the wall (9) of the container (1) that is
opposite to the convex wall (8). The atmosphere control element (2) is
embodied in the form of at least one hole (10) in the bottom (6) of the
container (1), and the selective gas-permeable membrane (11) is secured to
the bottom (6) and hermetically covers the holes (10). Bananas (3) are placed
in a row and their convex side faces the convex wall (8).
[00030] There can be just one hole (10) in the bottom of the container
(1) or there can be multiple holes (10) (Fig. 6 - Fig. 9). The holes can be
arranged in different ways, for example, in a line or in a circle, in the
cases
illustrated it is reasonable that the group of holes (10) would be covered by
one membrane (11).
[00031] On the bottom (6) of the container (1) there are convex areas
(12) (Fig. 3, Fig. 5) used to arrange a number of packages into a stack. This
would allow air to flow between the stacked containers.
[00032] A gas-permeable membrane can be composed of a micro-
porous film in the form of a polymer matrix, providing for a network of gas-
permeable pores. The material used for the selectively gas-permeable
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membrane (11) can be an industrially manufactured FreshPak membrane
commercially available from Landec. Examples of such membranes are
disclosed in US Patents 6,376,032 and 6,548,132, and PCT Application
WO 03/043447, all incorporated herein by reference.
[00033] Besides the indicated material, other multi-layer materials can
be used:
[00034] for example, Amcor - P - Plus Microperforated film, Cryovac
Oxygen Permeable multiplayer film (US Patent 6,294,210), Reusable Air
Permeable Film (US Patent Application 2005/0003150), Bubble Films (PCT
Application WO 2005/068194), as well as one-layer films: Stepac Film,
paRa Fresh, Fresh Span MACP, Fresh Hold Packaging, Silicone
Membrane, Teflon AF 2400 and Branched Polyolefin Membrane (US Patent
6,812,314).
[00035] The membrane (11) (Fig. 6 and Fig. 7) is secured to the bottom
(6) to hermetically seal the holes (10). In this case, the holes (10) should
be
small in diameter so that the membrane (11) does not become damaged
during the packaging process. However, to ensure the required rate of gas
exchange of the internal medium of the package with the atmosphere, which
is ensured by the corresponding surface of the membrane (11) staying in
contact with the atmosphere, its area should be higher than the total area of
the holes (10). This is ensured by the corresponding attachment of the
membrane (11). Part (13) of the membrane (11) is attached along the
perimeter (Fig. 6, Fig. 8) or around the holes (Fig. 7, Fig. 9) to the bottom
(6)
of the container (1), leaving parts (14) of the membrane (11) unattached.
[00036] The bottom (6) of the container (1), shown in Fig. 10 and Fig.
11, has a convex section (15) that faces the inside of the container (1) where
the atmosphere control element (2) is located. Holes (10) are located on the
convex section (15) of the container (1). The wall (16) of section (15) is
embodied as curvilinear and convex in the direction of the wall (8). This
embodiment will make the container (1) more rigid, stronger, and will prevent
the membrane (11) from accidental damage. Also, no additional convex
sections need to be introduced into the design of the bottom (6) of the
container (1) because even when stacked, the containers allow access for air
to the atmosphere control element (2).
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[00037] Fig. 12 and Fig. 13 represent another option for the convex
section (15). If there are no design elements in the bottom (6) of the
container
(1) to create a gap near the bottom (6) that allows air to access the holes
(10),
then a convex section (15) can be located near the wall (9).
[00038] During the packaging process, bananas (3) are placed in a
container (1) with the atmosphere control element (2). Bananas (3) are
placed in a row close to one another and are arranged with their convex
side to the convex wall (8) of the container (1) (Fig. 2).
[00039] Bananas (3) with a similar curvature are placed inside the
container (1). If bananas (3) with different curvatures are placed inside the
container (1), bananas with a lesser curvature should be placed near the
convex wall (8). In this case, bananas (3) could be arranged so that the
curvature of the bananas increases as the distance increases between the
banana and the convex wall of the container. Such arrangement of the
bananas (3) allows them to be packed densely. Due to the curvature of the
banana that is placed near the wall (9), access of the internal gas medium to
the unattached parts (14) of the membrane (11) is not blocked.
[00040] Bananas (3) can be placed inside the container in one layer, or
in several layers.
[00041] Also, the polymer film (7) is hermetically secured on the collars
(5) of the walls (4) of the container (1). This film prevents the access of
atmospheric air to the packed bananas and finishes the formation of the
assembled package.
[00042] While the bananas are being stored in the package,
atmospheric air passes through the holes (10) in the bottom (6) of the
container (1) to the external side of the unattached parts (14) of the
membrane (11). Through gas permeable parts (14) of the membrane (11),
gas exchange occurs by the difference in concentration of gas medium
components inside the package (1) and the external atmospheric air. An
atmosphere is generated inside the package, which has an oxygen content
that is lower than that of atmospheric air (approximately 2 - 4%) and carbon
dioxide content which is higher than that of atmospheric air (approximately 4
-7%).
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[00043] Concentration of oxygen and of carbon dioxide is maintained
inside the package due to atmosphere control element during the entire
period of banana storage (at the warehouse, grocery store, during the display
of bananas on the counter), so that the customer could observe them, and
even during the storage of the purchased banana pack on the customer's
kitchen counter, on condition that it has not been opened.
[00044] What is claimed is:
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