Method for packaging and storing fruits and vegetables

A method for packaging fruits and vegetables, where a fruit or portion of a fruit, or a vegetable or a portion of a vegetable are packaged forming a wrapped product for transport or storage, the wrapped product having an open surface area of at least two-percent. The method comprises perforating a shrinkable film having a pre-shrunk size and a shrunken size with a plurality of apertures so that the apertures are spaced at selected positions on the pre-shrunk size of shrinkable film. The fruit or the vegetable is then enclosed in the pre-shrunk size of the shrinkable film so that when the pre-shrunk size is converted to the shrunken size, the shrunken size film forms a tight enclosure around a portion of the fruit or vegetable, such as a crown portion, and has a girdle of apertures around an open area of the fruit or vegetable, such as a stem area.

BACKGROUND OF THE INVENTION 
1. Field of Invention 
This invention relates to methods for packing, storing, and transporting 
fresh and processed fruits and vegetables, and particularly to methods for 
packing, storing, preserving, and transporting vegetables such as broccoli 
for international shipments and enabling achievement of foreign and 
domestic quarantine requirements. 
2. Description of the Related Art 
Various methods and apparatuses have been proposed and implemented to 
effect the packing, storing, and transport of fresh and processed fruits 
and vegetables. The exportation of fruits and vegetables from the United 
States has increased dramatically in recent years. One area of rapid 
increase is the exportation of broccoli to Japan, recently achieving a 
volume of over 200 42-foot refrigerated sea containers in one week. Each 
sea container typically contains from 912 to 960 cartons of broccoli. The 
broccoli carton is additionally completely filled with ice and this 
included weight limits the amount of broccoli that can be delivered in the 
sea container to the port, or other domestic destination, because of 
United States Department of Transportation safety standards with regard to 
maximum transportable weight. 
Exporters of broccoli and other fruits and vegetables have been actively 
seeking other methods of delivering a greater number of vegetables in each 
container in order to reduce unit freight costs. One such approach uses 
controlled and modified atmosphere systems. The use of these 
controlled-gas systems retards the spoilage rate, or senescent decay of 
the vegetable, thus reducing the requirement for ice and the concomitant 
weight problems. However, such methods are limited by problems such as 
humidity control in transit, cost and technical requirements. 
In the United States, over-wrap and shrink-wrap packaging films have long 
been used by shippers and retailers to maintain cleanliness and reduce 
moisture loss in the packaging, shipping and transport of fruits and 
vegetables. The use of shrink-wrap film has begun to increase dramatically 
as a method to increase domestic freight efficiencies and also to provide 
a more attractive and longer lasting product. 
Both in the United States and Japan, retailers frequently over-wrap fruits 
and vegetables, and particularly broccoli, both domestic and imported, 
with plastic films to prevent handling abuse and to allow for placement of 
scanner tags or labels. Since labor cost are in general very high in 
Japan, there is great interest in receiving the product in that country in 
a wrapped state. Heretofore, however, this has not been possible because 
of the Japanese Plant Quarantine regulations. 
The Plant Quarantine Department in Japan is charged with protecting their 
island country from pests or diseases common to agricultural crops in 
other parts of the world. Their zeal and conscientiousness in carrying out 
this mandate is high. One requirement germane to the present methodology 
is a requirement with regard to the ability of a packaged vegetable or 
fruit to undergo fumigation, where that may be required as a result of 
inspection. That is, any packaged fresh fruit or vegetable must have 
minimum of 2% open area on its container. This includes cartons, bags, 
over-wraps, etc. In the case of shrink-wrap protected products, this 
standard also applies. 
Accordingly, there are broadly five difficulties which need to be resolved 
in formulating a method to satisfy the Japanese Quarantine requirements, 
which because or their rigorous nature, also will satisfactorily meet 
essentially all other quarantine and inspection requirements throughout 
the world: 
i) hole size 
ii) change in shape and dimension 
iii) hole making 
iv) product damage 
v) hole blockage 
With regard to (i) hole size; it must be adequate to consistently provide 
for open space in excess of 2%. If this is not satisfactory, and 
fumigation is called for, each wrap must be removed by hand salvage the 
product. Typically, the number of pieces may exceed 50,000 in a single 
container with prohibitive costs and product damage. 
Regarding (ii) change in shape; shrinking of the film changes the shape of 
the hole or holes, resulting in enlargement of the hole where tension is 
developed, and shrinkage where tension is lacking. This presents a risk 
with regard to minimum open space and also to the Japanese Plant 
Quarantine inspection interpretation of net hole size. 
As to (iii) hole making; the simple multiplication of pinholes is not a 
satisfactory method. The number of holes required may result in a web of 
film which is mechanically difficult to handle. In order to obtain the 2% 
coverage required in Japan, for example, there must be a pattern of holes 
such that their total open area relative to the final area of the shrunken 
film is at least 2%. For example, for a finished area of 600 square 
centimeters, a minimum of 12 square centimeters of open area is needed. 
For pinholes or punctures that are effectively 0.2 millimeters in 
diameter, approximately 400 holes are required. To account for changes in 
shape and product blockage of holes, a 10-fold multiple may be needed. 
Also, the use of these small holes is not productive since Japanese Plant 
Quarantine officials require a method that is straightforward and routine 
for examination of compliance. 
With regard to (iv) product damage and (v) hole blockage; if numerous holes 
are placed throughout the film widespread and spotty decay of the open 
space areas of the fruit or vegetable may result, and lead to a net open 
area of the film being deemed insufficient by inspectors. 
According, it would be highly desirable to have a method for eliminating 
the above described problems in the packaging, shipping and transport of 
fruits and vegetables. The present invention provides a simple but unique 
method to eliminate the above described problems and describes in 
particular, the placement of holes to take advantage of the morphological 
characteristics of broccoli and related vegetables so as to ensure that 
tension developed during shrinking of the film results in hole 
enlargement, and that the holes are spaced and positioned so as to prevent 
blockage by the product. 
It is a further object of the invention to provide a method for packing, 
and transporting fruits and vegetables which allows such fruits and 
vegetables to be packaged and shipped over extended distances involving 
significant time periods while preserving all of the critical and 
important characteristics of such fruits and vegetables while guaranteeing 
a commercially attractive product, and which is inexpensive to apply and 
highly efficient in results. 
Additional objects and advantages of the invention will be set forth in the 
description which follows, and in part will be obvious from the 
description, or may be learned by practice of the invention. The objects 
and advantages of the invention may be realized and obtained by means of 
the methods and combinations particularly pointed out in the appended 
claims. 
SUMMARY OF THE INVENTION 
The present invention provides a method for packaging fruits and vegetables 
allowing for domestic and international shipping of such produce while 
preserving all of the critical and desired characteristics of the produce. 
It is the principal purpose of the present invention to provide a method 
and means for applying such method so that fresh and processed fruits and 
vegetables may be conveniently yet efficiently packed in a manner so as to 
meet both domestic and international inspection and quarantine regulations 
while providing a high quality and long lasting product for consumer 
purchase. 
To achieve the foregoing objects, and in accordance with the purpose of the 
invention as embodied and broadly described herein, a method is provided 
for packaging fruits and vegetables, where a vegetable or portion of a 
vegetable, or fruit or portion of a fruit are packaged for transport or 
storage, comprising perforating a shrinkable film having a pre-shrunk size 
and a shrunken size with a plurality of apertures so that the apertures 
are spaced at selected positions on the pre-shrunk size of shrinkable 
film. Then the fruit or vegetable is enclosed in the pre-shrunk size of 
the shrinkable film so that when the pre-shrunk size is converted to the 
shrunken size, the shrunken size film forms a tight enclosure around a 
portion of the fruit or vegetable, such as the crown, and has a girdle of 
apertures around an open area, such as the stem portion, defined by the 
morphology of the fruit or of the vegetable. 
The method of the present invention is preferably used with vegetables such 
as broccoli. However, in alternative applications the method of the 
present invention may be applied for use with other vegetables and fruits. 
In fact, the particular application is dependent only upon the 
requirements of the user as a wide range of fruits and vegetables could be 
packaged, stored and transported using the methodology described herein.

DESCRIPTION OF THE PREFERRED EMBODIMENTS 
Reference will now be made in detail to the present preferred embodiments 
of the invention as illustrated in the accompanying drawings. 
Accordingly, a method is provided for packaging fresh and processed fruits 
and vegetables, where a vegetable or portion of a vegetable, or fruit or 
portion of a fruit are packaged for transport or storage, comprising, 
perforating a shrinkable film having a pre-shrunk size and a shrunken size 
with a plurality of apertures so that the apertures are spaced at selected 
positions on the pre-shrunk size of shrinkable film. Then the fruit or 
vegetable is enclosed in the pre-shrunk size of the shrinkable film so 
that when the pre-shrunk size is converted to the shrunken size, the 
shrunken size film forms a tight enclosure around a crown portion of the 
vegetable and has a girdle of apertures around a stem portion of the 
vegetable. 
There is also provided, in accordance with the invention a method of 
packaging broccoli, or Brassica oleracea botrytis, other members of the 
mustard family such as cauliflower, and other fruits and vegetables, where 
the fruit or vegetable is packaged for transport forming a wrapped 
product, the wrapped product having an open surface area of at least 
two-percent, comprising: perforating a shrinkable film having a pre-shrunk 
size and a shrunken size with a plurality of apertures so that the 
apertures are spaced at selected positions on the pre-shrunk size of 
shrinkable film. The broccoli, or other fruit or vegetable, is then 
enclosed in the pre-shrunk size of the shrinkable film so that when the 
pre-shrunk size is converted to the shrunken size, the shrunken size film 
forms a tight enclosure around a crown portion of broccoli, and has a 
girdle of apertures around a stem portion of the broccoli. 
In FIG. 1, a flow diagram is shown outlining the preferred steps of the 
method of the present invention. In step 1, a shrinkable film 12, having a 
pre-shrunk size 14 and a shrunken size 16, is perforated with apertures 18 
when in pre-shrunk size 14. The apertures are preferable sphericaly 
shaped, however, other geometric shapes may be used, such as oval, 
rectangular, triangular, and the like, in alternative embodiments. 
Apertures 18 may be placed in shrinkable film 12 in a wide variety of ways 
such as using a pinwheel device attached to a conventional packaging 
machine, using any stamping or boring device capable of making apertures 
in a controlled manner in film or plastics such as electrically powered 
devices, or by manual cutting or stamping of the apertures in the film. It 
will be apparent that the positioning of apertures 18 may be varied 
depending upon the packaging machinery chosen both in terms of size and 
positioning. It is also apparent that depending upon the size and shape of 
the fruit or vegetable, or portion thereof to be packaged, the size of 
apertures 18 will vary. Preferably apertures 18 are of uniform size which 
is generally more practical in application, however, this need not be the 
case. The precise number of apertures 18 may vary and within the 
methodology herein disclosed may be modified and related to the type of 
shrinkable film used, it thickness, the heat used to shrink the shrinkable 
film, the time of film exposure to a given amount of heat, the overall 
envelope of film needed to bag the product, and the desired relative final 
open space represented by the apertures in the film. 
The shrinkable film 12 may be high density, mid-density, or low density 
breathable polyethylene for example, or other non-surface adhering 
thermoplastics may be utilized such as linear low density polyethylene, 
polypropylene, polystyrene, biaxially oriented polypropylene, vinyl 
acetate copolymers, polyvinyl chloride, mixtures or the foregoing, 
multilayer films of the foregoing, and other polymers and copolymers. A 
critical characteristic of any film or membrane used is that it is capable 
of undergoing shrinking, that is, being converted from the pre-shrunk size 
14 to a shrunken size 16 in response to heat or other selectively applied 
force. 
In step 2 of the flow chart shown in FIG. 1, the fruit or vegetable, or cut 
portion thereof, is then enclosed in the pre-shrunk size 14 of the 
shrinkable film 12. Then the pre-shrunk size 14 is converted to the 
shrunken size 16, for example, by passing it through a heat tunnel or 
other heat controlled environment. In practice, it is preferable to effect 
shrinkage of shrinkable film 12 by a quick passage through a heat tunnel 
so as to preclude heat build up in the packaged produce. The shrunken size 
film 16 forms a tight enclosure around a crown portion 20 of the fruit or 
vegetable 10. Apertures 18 are preferably positioned so that a girdle of 
apertures 22 is formed which encircle the stem portion of the fruit or 
vegetable, or open environment 24, as seen in FIG. 2. 
With reference to FIG. 3, it is seen that apertures 18 placed in shrinkable 
film 12 when in the pre-shrunk size 14 comprise in excess of 1% of the 
surface area of the pre-shrunk size 14. Following heat treatment or other 
shrinking or stretching of film 12, preferably when the film is enclosing 
the fruit or vegetable, aperture 18 preferably constitute 2% to 3% of the 
surface area of shrunken size 16 of shrinkable film 12. It will be 
apparent, that for films with varying shrink and stretch characteristics, 
that varying amounts of aperture or open hole space may need to be 
provided to achieve the desired results. 
An example of the preferred methodology of the present invention was the 
preparation of broccoli harvested for export to Japan. The broccoli was 
harvested in single stalks with uniform crown diameter of about 115 mm to 
140 mm, preferably 120 mm to 135 mm with an overall length of 125 mm to 
135 mm and placed in plastic totes. The broccoli was brought to a central 
processing site for cooling and packaging, which may be in either order. 
The broccoli was then packaged using the method of the present invention. 
There are several packaging machines available to effect the packaging of 
produce. In the present case, a Rennco Model 101 was used. However, other 
machines such as those known in the trade as L-bar scalers may also be 
used. A shrinkable film is then selected, in this case a standard 60 gauge 
(0.060 inch) thickness of a circular configuration making up about 1.2% of 
the surface area of the pre-shrunk size of the shrinkable film. The film 
was guided through the machine in a folded, bi-layer form, then the fold 
was opened either mechanically, or by hand for insertion of the broccoli, 
and then the film enclosed around the broccoli to fom a bag. The film was 
then passed through a heat tunnel to effect film shrinking. When shrunk 
the apertures constituted between 2-3% of the surface area of the film 
forming a girdle around the open section of the broccoli while fitting 
tightly around the crown and bud portion. Test shipments of the packaged 
broccoli was shipped to Japan by sea container with a transit time of 12 
days under standard refrigerated conditions and controlled atmosphere in a 
refrigerated sea container. Subsequent storage was extended for over four 
weeks with excellent quality retention. 
As seen in FIG. 2, by providing apertures 18 such that their relationships 
to the shrunken size 16 of shrinkable film 12, the packaging, and the 
harvested produce, such as broccoli, provide a row or girdle of apertures 
so that after the broccoli is enclosed in the film in an oriented 
position, the shrunken size film 16 forms a tight enclosure around the 
crown 20, leaving a girdle or row of apertures around the open environment 
24 around the vegetable. Of course, the present method may be used with a 
wide variety of fruits and vegetables, such as cauliflower, carrots, 
grapes, and the like. 
In operation and use the method of the present invention is highly 
efficient, cost effective, and easy to implement. The method of the 
present invention may be implemented in a produce room, packing house, in 
the field, or any other suitable building or location. The shrinking of 
the film achieves the desired effect, where the apertures are enlarged to 
remain in excess of, for example, Japanese Plant Quarantine requirements. 
The present method provides a plurality of apertures which are not blocked 
and are strategically positioned. The tight enclosure around the crown of 
the vegetable or fruit by the film allows for improved moisture retention 
and minimal oxidation, and if a fumigant is required, it may move freely 
in through the apertures, in accordance with the Japanese Plant Quarantine 
requirements, for example. 
The method of the present invention as herein described in detail may be 
used with either fruits or vegetables, however, it is most conveniently 
used with vegetables such as broccoli, thereby allowing for the year-round 
supply of fresh supply of produce to both domestic and international 
consumers with all of the key and critical characteristics preserved. By 
providing an economical and efficient means to achieve accordance with 
international and domestic regulation and quarantine requirements, the 
present invention vastly increases the potential market size for such 
produce, while reducing product spoilage and loss, and minimizing 
confiscation and entrance denial by regulatory authorities. 
Additional advantages and modification will readily occur to those skilled 
in the art. The invention in its broader aspects is, therefore, not 
limited to the specific details, representative apparatus and illustrative 
examples shown and described. Accordingly, departures from such details 
may be made without departing from the spirit or scope of the applicant's 
general inventive concept.