Note: Descriptions are shown in the official language in which they were submitted.
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APPARATUS AND METHOD OF ASEPTIC PACKAGING PERISHABLES
CROSS-REFERENCES TO RELATED APPLICATIONS
This application is a continuation of application No. 09/393,412, filed
September 10,
1999, now U.S. Patent No. 6,135,015, which is a continuation-in-part of
Application No.
091309,387, filed June 18, 1998, which is a continuation-in-part of
Application No. 08/823,813,
filed March 24, 1997, abandoned, which is a continuation of Application No.
08/442,188, filed
May 16, 1995, now U.S. Patent No. 5,614,238.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention is directed to an industrial apparatus for preserving
perishables,
such as fresh squeezed citrus and non-citrus fruit juices, fruit juice blends,
fruit pulp, dairy
products, barley products, soups, and soft drinks. More particularly, the
industrial apparatus
enables a thermal preservation process for aseptically packaging perishables
without adding
preservatives.
The invention also encompasses an industrial apparatus for treating perishable
products
(including fruit juice, fruit juice blends, fruit pulp, wines, milk, chocolate
milk, butter, yogurt,
cultured milk products, beer, malt and oat beverages, soups, and soft drinks)
in order to extend
their shelf life.
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2. Description of the Prior Art
When fruits are harvested, microbiological and chemical changes occur which
limit the
time the fruit remains acceptable to the consumer and is safe for consumption.
Since most of the
post-harvest changes in food lead to spoilage, various methods of food
preservation are used to
prolong the length of time far which the foods retain their original quality
and appeal.
In the days of simple farming communities, the population lived on locally
grown fruits
and vegetables. As a result, no highly organized methods of food preservation
were necessary.
In the modern world however, centers of world population are in towns and
cities, that
are often many miles from the main areas of food production. To provide
unspoiled food to these
distant consumers, methods and chemicals were developed to preserve food.
Unfortunately,
long-term tests have shown how these same chemicals can harm the very people
intended to be
protected.
After harvesting, plant tissue is unable to prevent the attack of
microorganisms such as
bacteria, yeast, and molds, which break down the food structure and produce
undesirable "off
flavors," discoloration, and odors. The number of organisms in an ounce of
food can range from
several hundred to twenty million or more and the organisms are capable of
rapid multiplication,
such that under certain conditions, their numbers can double every fifteen or
twentyr minutes.
Bacteria are minute microorganisms that are the most common cause of food
spoilage.
Bacteria also can render the food unpleasant to eat. And, in the case of
pathogenic bacteria, such
?0 as Staphylococcus aureus or Clostridium botulinum, bacteria may cause far
worse effects
including foad poisoning.
Food spoilage is also caused by chemical substances known as enzymes which are
always
present in minute quantities in living materials. Enzymes are proteins that
catalyze biochemical
reactions. Enzytncs catalyze the chemical reactions that change the flavor and
texture of fruits
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during ripening. Enzymes are also responsible for the deterioration of fruits
after harvesting,
such as the browning of the cut surface of apples and pears caused by the
oxidation of phenols
by the enzyme phenolase.
Because enzymes are proteins, enzymes are heat sensitive. Most proteins
irreversibly
denature when heated above normal biological temperatures. When proteins
denature, they
unravel and Iose their three-dimensional shape. Because the ability to
catalyze reactions depends
on shape, once enzymes are heated, they usually lose their ability to catalyze
reactions.
Thermal preservation techniques for rendering inactive bacteria and enzymes in
fruit
juices and citrus pulp typically rely on known, large-scale, pasteurization
techniques.
Pasteurization is a heat treatment process, wherein a supply of food product
is heated in stainless
steel containers at temperatures normally less than 212° F
(100°C). Although common
pasteurization techniques destroy pathogenic organisms, they do not provide
indefinite protection
against microbiological spoilage. Products that have been pasteurized need to
be refrigerated
immediately. Pasteurization extends shelf life to four to seven days in diary
products and four
to six weeks in fruit products.
Even an acidic product, such as fruit juice, requires protection from spoilage
organisms
such as acetobacter, whose growth can lead to cloudiness in the fruit juice
product. Cloudiness
in some citrus juice products is due to the presence of pectin, which occurs
naturally in the fruit.
If the natural pectolytic enzymes of the fruit are not destroyed, they degrade
the pectin with the
?0 result that the juice becomes cloudy and often gels. Therefore, in order to
destroy the pectolytic
enzymes, most citrus juices are processed by flash pasteurizing in a plate
heat exchanger at ~ 03 ° F
(95°C) for 30 seconds. However, v~~hile partially rendering enzymes
organically inactive, this
process degrades juice quality since the juice in contact with metallic heat
exchanger elements
reach temperatures above 100°C. 'the product that directly contacts the
heating surface may
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actually become cooked if exposed to heat for more than thirty seconds.
Cooking causes
irreversible changes in the taste, color, and odor of food. Furthermore, the
prior art methods have
been found unsatisfaetor5~ for rendering the enzymes present in citrus and non-
citrus fruit juices
organically inactive or destroying bacteria and other pathogenic and non-
pathogenic organisms.
'the short shelf life of pasteurized products evinces the shortcomings of
current methods.
Placing heating elements in direct contact with malt beverages also may alter
the taste,
color, and odor. When malt beverages such as beer are directly heated by
heating elements that
are above one-hundred-sixty-five degrees centigrade (165°C~, the
original taste becomes
affected. To prevent overheating, malt beverages may not be fully pasteurized
with the result that
many harmful bacteria and enzymes remain. Fresh barley products have a similar
shelf life to
mi 1k.
Pasteurization techniques do not render one-hundred percent of the enzymes in
these
products organically inactive. As a result, certain fruit juices have not been
made readily
available to the consuming public due to the limited success of the prior art
methods. For
example, juices such as watermelon juice, banana juice, grape juice, and
pineapple juice are not
found on store shelves packaged in a one hundred percent natural state.
Caftentimes, the juice
duality is compromised by the addition of various preservatives to maintain
freshness and color.
Fresh dairy products may be more sensitive to enzymes than fruit products.
Pasteurized
milk only lasts four to seven days even when refrigerated.
~0 Thus, a need still exists for an industrial apparatus for the thermal
processing of fresh fruit
products, fresh dairy products, and fresh barley products which will result in
the aseptic packing
of these products without the addition of preservatives to extend the shelf
life of the products up
to two to three years without refrigeration.
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SUMMARY OF THE INVENTION
The instant invention teaches a process that effectively kills, or renders
organically
inactive, ono-hundred percent of the bacteria and enzymes, as well as any
other non-pathogenic
microorganisms present in fresh squeezed citrus and non-citrus fruit juices
and fruit juice blends,
as well as fruit pulps, wines, dairy products such as milk, barley products
such as beer, soups, and
soft drinks. The process results in the aseptic packaging of natural juices
having a shelf life
extending from two to three years without the need for refrigeration or
artificial preservatives.
The industrial apparatus and process also preserves the natural taste, colors,
and aromas typically
found in fresh squeezed juices, juice blends, and fruit pulp, while avoiding
the disadvantages of
overheating experienced in plate heat exchangers.
The process includes the following steps: extracting the juice or pulp
(hereinafter "juice")
in a conventional manner using a juice extractor; placing the extracted juice
immediately into
temperature-resistant containers capable of withstanding temperatures greater
than 100°C;
submerging substantially the containers in a tank of water at room
temperature; raising the
temperature of the water in the tank to 100 °C within a time period
between five and ten minutes
(5-10 min); monitoring the juice temperature until the juice reaches a minimum
temperature of
92°C and a maximum temperature of 97°C; allowing the juice to
remain at a temperature
between 92"C and 97°C for a time between one and two minutes (1-2
min.); remov=ing the
containers from the water; capping the containers in an airtight manner;
cooling the containers
'_'0 to approximately 35°C by suitable moans such as rinsing with room-
temperature water and
passing cold air, thereby causing a vapor lock inside the individual
containers caused by the
volumetric contraction of the enclosed vapor during cooling, and preventing
continued heating.
In addition, the process may add the following steps: stabilizing the juice
for three days; checking
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for fermentation, contamination, leaks, or other defects by confirming the
vapor lock that has
been maintained; and labeling, boxing, and shipping the containers for
consumption.
The invention can apply the principles taught in U.S. Patent 5,614,238
(obtained by the
same inventor) to a process wherein massive amounts of fresh perishables are
preserved. These
perishables include fresh fruit products, fresh dairy products, fresh barley
products, soups, and
soft drinks. The invention encompasses an industrial apparatus that allov~~s
the processing of
massive amounts of fresh perishables. Also, this industrial apparatus permits
the aseptic
packaging of larger container sizes. Also, since the product is never in
direct contact with the
heat source, the perishables retain their natural aroma, flavor, color, and
appearance.
The invention encompasses the following industrial apparatus and methods. The
perishables are placed in a tank. 'The tank is jacketed. In the jacket, a
heating medium is
enclosed. 'the heating medium is preferably a high thermal capacity material
that is a liquid
between room temperatures and 100° C'. Preferably, the heating medium
is water but other
products can be utilized, such as ethylene glycol and mineral oil. The heating
medium is directly
heated by a heat source. The heat source can be any heating device such as a
heating coil or
steam boiler. Because the perishable is heated by the heating medium which, in
turn, is heated
by the heat source, the perishable can be said to be heated "indirectly" by
the heat source. In
contrast, the heating medium which is in contact with the heat source can be
said to be heated
"directly" by the heat source. By indirectly heating the perishable, the
perishable is never
exposed to the extreme heat of the heat source. Anather advantage of using a
heat medium is that
it provides a large, efficient heat sink through which large amounts of
thermal energy can be
quickly transferred.
To guarantee that all of the perishables in the tank arc properly heated, the
tank can
include a means fur miring the perishables. The means for miring include an
agitator, internal
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baffles to create mixing during flow, and villi which increase the surface to
volume ratio to
enhance heat transfer. 'the industrial apparatus includes temperature sensor
to monitor the
temperature of the perishable throughout the process.
After heating, the product is hot bottled, capped, cooled, and labeled in a
typical fashion
to create a vacuum sealed product.
The invention can be a batch process. In a batch process the tank is filled
with
perishables, the perishables are heated, and then the entire tank is emptied
and the perishable is
dispatched for bottling.
The invention can be a continuous process. In a continuous process, the
perishable is
flowed continuously through the tank. The flow, mixing, and heat exchange is
controlled within
the tank so that whenever a perishable is flowed through the tank, it exits
having been fully
heated according to the method described in the previous paragraphs.
Throughout the continuous
process, perishables flow into and out of the tank. By being a continuous
process that constantly
produces treated perishables, the filler can be operated constantly without a
v~~ait between batches.
The invention lengthens the shelf life of the perishables including the
following products:
fruit juice, fruit juice blends, fruit pulp, wines, milk, chocolate milk,
butter, yogurt, cultured milk
products, beer, malt and oat beverages, soups, and soft drinks.
Therefore, an object of the instant invention is to provide a thermal
preservation method
for products such as citrus and non-citrus fruit juices, fruit juice blends,
and fruit pulps, whereby
?0 one-hundred percent natural juice or pulp praducts may be aseptically
packaged in air tight
containers having an extended, non-refrigerated, shelf life of at least two
years.
A further object of the instant invention is to provide a thermal preservation
method
whereby juice and pulp products are prevented from overheating contact with
heat exchanging
industrial apparatus.
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Yet another object of the instant invention is to provide a thermal
preservation process
whereby juice and fruit pulp products are packaged prior to exposure to raised
temperatures.
Still another object of the present invention is to provide a thermal
preservation process
whereby pre-packaged juice ar pulp containers vents vapor during the heating
process and create
a vapor lock during the cooling process.
Yet another object of the instant invention is to provide a thermal
preservation process
suitable for use with perishables such as fruit juice, fruit juice blends,
fruit pulp, wines, milk,
chocolate milk, butter, yogurt, cultured milk products, beer, malt and oat
beverages, soups, and
soft drinks.
An object of the invention is to provide an industrial apparatus that can
aseptically
package perishables wherein the speed of the device is not limited by the time
of heating and
coating the containers.
An object of the invention is to provide an industrial apparatus wherein full
containers
need not be dipped and lifted in a bath for heating and cooling.
An object of the invention is to provide an industrial apparatus that
denatures the enzymes
in perishables that are responsible fox spoilage while not affecting the
taste, color, and aroma of
the fresh perishable.
An object of the invention is to provide an industrial apparatus capable of
continuously
processing perishables so as to lengthen their shelf life.
~0 In accordance with these and other objects which will become apparent
hereinafter, the
instant invention will now be described with particular reference to the
accampanying drawings.
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BRIEF DESCRIPTION OF THE DRAWINGS
Figure 1 illustrates the container filling procedure.
Figure ? illustrates capping of a container.
Figure 3 illustrates the containers submerged into a water bath and heating
procedure
wherein the water temperature is raised.
Figure 4 illustrates a capping process forming an air tight seal.
Figure 5 illustrates cooling the containers with a water spray.
Figure 6 illustrates the containers during the stabilization and inspection
stage.
Figure 7 illustrates the final labeling and packaging stage.
Figure 8 is a flow chart of the instant process.
Figure 9 is a schematic diagram of an industrial apparatus capable of
processing large
amounts of perishables.
Figure 10 is a table showing the deactivation of enzymes as a function of the
product
being heated to different temperatures.
Figure 11 is a side, cross-sectional view of the tank and surrounding layers
shown in
Figure 9.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The invention encompasses a process that kills, or renders organically
inactive, one-
hundred percent of the bacteria and enzymes, as well as any ather non-
pathogenic
microorganisms present in fresh squeezed citrus and non-citrus fruit juices
and fruit juice blends,
as well as fruit pulps, wines, milk, chocolate milk, butter, yogurt, cultured
milk products, beer,
malt and oat beverages, soups, and soft drinks. The process results in the
aseptic packaging of
one hundred percent natural juices having a shelf life extending from two to
three ~°ears without
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the need for refrigeration, and without the use of artificial preservatives or
additives. The process
also preserves the natural taste, colors, and odors typically found in fresh
squeezed juices and
juice blends, and fruit pulp.
Figure 8 is a flow chart of the process taught by the instant inventian. The
process
includes the following steps. Extracting the juice or pulp using an
appropriate extracting device
as illustrated in Figure 1. For example, a citrus juice extractor 10 may= be
utilized to extract juice
and pulp from citrus including oranges, tangerines, and grapefruit. On the
other hand, fruit, such
as bananas, may require more specialized extracting devices. Regardless of the
extraction
method, one-hundred percent natural juice or pulp, showm generally as 12, is
obtained.
The extracted juice, juice blend, or fruit pulp (hereinafter "product") is
immediately
bottled in temperature-resistant containers 14 such as thermoplastic capable
of withstanding
temperatures possibly exceeding one-hundred degrees Celsius (100°C).
Temperature-resistant
polymeric containers are particularly well suited for use with the instant
process since the
polymeric wall acts as a thermal insulator that protects the product from
exposure to the extreme
surface temperatures experienced while heating theproduct in a thin wall
stainless steel container
or plate heat exchanger. Polymeric containers are also able to withstand
thermal expansion better
than other possible materials such as glass.
As best seen in Figure 2, the filled containers 14 may be capped with a
suitable
commercial cap 16, however, in the preferred embodiment the containers are not
initially capped.
In addition, as an alternative, the containers may be "partially capped" which
refers to capping
the container by imparting a partial turn to the cap such that the cap is semi-
sealed and vapor and
gas remaining in the container may escape during expansion.
As best shown in Figure 3, the containers 14 are then substantially submerged
in a tank
18 of water which is initially at room temperature. It has been found that
submerging the
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container such that the exterior water level reaches approximately tv~~o-
thirds to three-quarters
of the container height is aptimum. Tank 18 is preferably constructed having
an elevated, or
double bottom, shown as 20, for elevating the containers above a heat
exchanging means 22. In
the preferred embodiment, the heat exchanging means includes a steam heat
exchanger, having
a steam inlet 24 and a steam outlet 26, submerged within tank 18 with heat
supplied by
superheated steam.
The temperature of the water in the tank is then raised to eighty degrees
centigrade (80°C)
over a period of approximately five (5) minutes. Thereafter, the temperature
of the water in the
tank is further raised to at least ninety-two degrees centigrade
(92°C') over an additional two
minute (2 min.) period. As the temperature of the water in the tank is
uniformly raised,
temperature sensors (not shown) monitor the product temperature. To insure
uniform heating,
the product may be mixed by agitating the containers. The heat transfer
process is terminated
when the juice product reaches ninety-two degrees centigrade ()2°C).
The product should not
be heated above ninety-seven degrees centigrade (97°C). The juice
product, however, may be
I 5 maintained at that temperature for a few ( I -3) minutes, depending on the
product to deactivate
organic matter such as bacteria and enzymes.
'The containers are then removed from the tank and capped if previously left
uncapped,
or "totally capped" as best illustrated in Figure ~ if the partial capping
method is used. "'Totally
capped" is defined as securing the cap in an air tight manner, typically by
imparting an additional
twist to the cap 16. As best depicted in Figure 5, the product is then
partially cooled on specially
designed cooling racks 30, using spray 32 of room-temperature (~?5 °C)
water, thereby producing
cooling induced volumetric contraction of the liquid and vapor in the
containers which produces
a vapor lock, thereby causing the pop-up portion of the pop-up cap to become
depressed (not
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shown) indicating a positive seal. Unce a vapor lock is achieved, the
containers are allowed to
further cool at ambient conditions to room temperature (approximately
35°C).
As best illustrated in Figure 6, the product should then be allowed to
stabilize for
approximately three days, during which time the product undergoes duality
control inspections
to detect any fermentation, contamination, leaks, or defects in the vapor lock
seal.
The resulting product is then labeled, boxed and shipped for consumption as
illustrated
in Figure 7. Product made by the instant process has an extended shelf life of
over 2 years
without refrigeration.
Figures 9 and 11 depict an industrial apparatus and related method for the
preservation
of large volumes of perishables. The industrial apparatus and method prevent
discoloration
resulting from ohidation in a conventional manner using an industrial method
which can be
modified to suit each product.
Perishables 100 are placed in holding tank 105. Holding tank 105 is preferably
made
from a material such as stainless steel. From holding tank 105, perishables
100 can be moved
to tank 1 O 1. Pump 106 can be included in the connection between holding tank
105 and tank 101
to help move perishables 100. Holding tank 105 can include a means for mixing
perishables 100
such as an agitator 107. The preferred embodiment of the industrial apparatus
includes tank 101.
Tank 101 holds perishables 100 for processing. Tank 101 can be made of any
industrial food
approved material that can resist the required temperatures. Jacket 102
surrounds tank 101.
Heating medium 103 ills jacket 102 to surround tank 101. Heating medium 103
transfers heat
with perishable 100 through the walls of tank 101. Heating medium 103 is
preferably a liquid
having a high-thermal capacity between room temperature and the boiling point
of the perishable,
generally twenty-five to one-hundred degrees centigrade (25 - 100°C).
Preferred heating
mediums 103 include water, ethylene glycol, and mineral oil. Heat source 10~
directly heats
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heating medium 103. Heat source 104 can have a temperature above one-hundred
degrees
centigrade {100°C) because heat source 104 does not directly
contaetperishable 100. Preferred
forms of heat source 104 include steam boilers and heating coils.
Once in tank 101, perishables I00 are heated through the walls of tank 10I by
heating
medium 103. Heating medium 103 is heated by heat source 104. Perishables 100
are heated in
tank 101 to a temperature between ninety-two and ninety-seven degrees
centigrade (92 - 97°C)
for a period of lime between one and two minutes (1 - 2 min.).
Figure 10 is a table showing the effect of heating perishables 100 to
different
temperatures. The experiments show that the heating of products of
temperatures approaching
one-hundred degrees centigrade (100°C) denatures the enzymes within
these products which
prevents these same enzymes from spoiling the products. The data in Figure 10
shows that the
percentage of inactivation of enzymes depends on the temper°ature to
which the product is heated.
Additional experiments have shown that heating products above 100° C
also deactivate
enzymes, but at the cost of taste, color, and aroma. When heated above the
boiling point, the
taste of perishables I00 is irreversibly changed. After boiling, the color
becomes brown and the
taste and aroma are changed.
Tank 101 is connected to filler 108. Filler 108 hot fills containers 109 with
processed
perishables 100 while perishables 100 are still above room temperature. Pump
114 is preferably
a centrifugal pump that moves perishables 100 from tank 101 to filler 108.
Containers 109 are
?0 preferably made out of material that withstands temperatures of at least
one-hundred degrees
centigrade (I00° c) such as thermoplastic and glass.
A means fur transporting containers 109 such as a conveyor belt 115 transfers
containers
109 to capper I 10. C upper 1 10 places cap 1 11 on each of containers 109
while perishables 1 O1
are Still hot within containers 109. A means fur cooling containers 1 D9 such
as v~iater spray 1 1 ~',
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cold air (not shown), or cooling tunnel cool containers 109 and perishable 100
causing the
contents of containers 109 to volumetrically contract. This creates a vacuum
seal v~~ithin
containers 109. The vacuum seal can be monitored to verify freshness and seal
of the bottled
perishable.
Tank 101 can also include a means for increasing heat transfer. '),he means
for increasing
heat transfer can include baffles 113, agitator {not shown), and villi (not
shown). The means for
increasing heat transfer is designed to increase the transfer of heat between
heating medium 103
and perishables 100. By making heat transfer more even and more efficient,
perishables 100 can
be processed quicker without overheating localized portions of perishables
100. Without means
for increasing heat transfer, larger applications where the surface area to
volume ratio of tank 1 O 1
is love may be impossible to heat evenly. Baffles 113 and agitators {not
shown) within tank 101
increase mi~:ing and cause perishables 1 QO to be evenly heated. Villi (not
shown) are finger-like
extensions that increase the surface area to volume ratio and thereby
facilitate heat transfer.
A preferred form of this industrial apparatus can be used in a batch process.
Generally,
I S in batch processes, one allotment is processed at a time. In this
invention, tank 101 is filled with
perishables 100 and perishables are processed, then tank 101 is emptied. Once
emptied, the
process is repeated.
Another preferred form is a continuous process. In a continuous process, a
constant flow
of perishables is maintained throughout the system. To permit a continuous
process in which the
~0 perishables exit tank 101 having all been adequately heated but not
overheated, the mixing in and
flow rate through tank 101 must be adjusted.
The instant invention has been shown and described herein in what is
considered to be
the most practical and preferred embodiment. It is recognized, however, that
departures may be
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made therefrom within the scope of the invention and that obvious
modifications will occur to
a person skilled in the art.
IS
