Note: Descriptions are shown in the official language in which they were submitted.
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COLD SHOCK METHOD IMPROVEMENTS
BACKGROUND
It is well known that chilling food products reduces bacterial growth and
retards the onset of spoilage, thereby increasing shelf life. However, in the
past 20
years, it has become known that some microorganisms have been able to adapt to
a
period of such chilled, low growth temperature. In response to this ability to
adapt,
recent investigations into the cold shock responses of various microorganisms
have
been conducted. It has been found that cold shocking can introduce stresses
affecting biological structures, which can fatally injure the microorganism,
or weaken
the microorganism and make it more susceptible to antibacterial or
disinfecting
agents. Various difficulties have been associated with the attempts that have
been
made so far to try to rapidly cool food and thereby effectively introduce such
a cold
shock procedure into food processing.
One attempt at using cryogenic liquids for cold shocking a food product is
described in U.S. Pat. No. 4,325,221, where animal carcasses are sprayed with
liquid nitrogen. This disclosure teaches that the surface membranes of the
carcass
are to be rapidly frozen in order to seal in the loss of moisture from the
carcass. The
principle desired effect is to reduce moisture loss from the product.
Another attempt is described in U.S. Pat. No. 4,367,630, where carcasses are
immersed into a tank of cryogenic fluid to crust-freeze the exterior. Again,
the
desired effect is to reduce valuable weight loss of the carcass.
Yet another attempt is described in U.S. Pat. No. 4,940,599, where the
surface of fresh meat is subjected to a cryogenic liquid just long enough to
form a
layer of ice, but not long enough to freeze the outermost, and innermost,
layers of
flesh on the carcass. The desired effect is to reduce spoilage in the
appearance of
the outermost layer of the flesh.
CONFIRMATION COPY
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Another attempt is described in U.S. Pat. No. 5,471,846, where a mass of
food product is introduced into a storage compartment, then into which an
amount of
cryogenic liquid is introduced, as a function of the weight of the food
product present.
The desired effect is to increase the overall efficiency of the chilling
process using
cryogenic liquids.
Another attempt is described in U.S. Pat. No. 5,577,392, where a cryogenic
chiller is disclosed that uses a vortical flow pattern. The desired effect is
to sweep
any liquid or solid cryogen from the bottom surface of the tunnel and
recirculate it
around the food product.
There is also a need to disinfect and sanitize non-food objects, such as
surgical, dental or laboratory instruments, prosthetic joints, dentures and
similar
objects. Traditional processes for sanitizing such objects have utilized
steam,
ethylene oxide, ionizing radiation, formaldehyde, and hot air. Within the past
decade, new processes have been introduced that include peracetic acid,
chlorine
dioxide, plasmas, and ultva-violet light.
Each of these references suffers from the disadvantage that either the germs
on the very surface, or just below the surface, of the object are not actually
cold
shocked. There is no control of the application of the fluid to obtain the
desired
effect of cold shocking the surface pathogens. There is no additive introduced
into
the fluid-.
For the foregoing reasons, there is a need for a method for cold shocking food
that allows control of the submerging of objects into a fluid to obtain a
desired
cooling effect. It would be an advance in the art of disinfection to couple
this
resulting cold shock effect with either the prior, concurrent, or subsequent
application
of an additive within the cryogenic fluid. There is a need in the industry for
such an
additive to further assist in the sanitation process.
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SUMMARY
The present invention is directed to a method that satisfies the need in
society
in general for a method for cold shocking food, or non-food objects, that
allows
control of the submerging of objects into a fiuid, wherein this fluid has an
additive, to
obtain a desired cooling effect. The present invention is also directed to a
method
that satisfies the need to combine this resulting cold shock effect with
either the prior,
concurrent, or subsequent application of an additive within the fluid, wherein
this
additive is preferably an aid to sanitation.
This method comprises a method of cooling objects by submerging the
objects in a fluid, where the fluid has an additive, and where the submergence
is
regulated to obtain desired cooling and sanitizing effects. These objects may
be
either food or non-food objects. The fluid may be liquid nitrogen, liquid
argon, liquid
oxygen, liquid carbon dioxide, or any combination thereof.
This additive may be something that participates in the desired sanitation
process of the object. The objects may be exposed to the disinfecting additive
prior
to, coincident with, or subsequent to the actual cooling treatment. The object
may
be exposed to the same, or different, additive before the cooling process,
then may
be exposed again during or after the cooling process. This additive may be an
ozidizing agent such as ozone, chlorine, chlorine compounds, hydrogen peroxide
solutions, oxonia solutions, or combinations thereof.
Oxonia is known to one skilled in the art to be a solution composed of either
hydrogen peroxide and peristaltic acid, or hydrogen peroxide and peroxyacetic
acid.
The submergence may be by way of an automatic dipping process, or a
continuous moving belt process. The regulation may occur by varying speed or
maintaining a constant speed. The submergence may be by way of total
submergence, or only partial submergence, of the object in the cryogenic
liquid.
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The desired cooling effect may be to shock the surface microorganisms to
make them susceptible to concurrent or subsequent treatments. The desired
cooling
effect may be to promote the destruction and/or the inactivation of the
surface
microorganisms without cooling or freezing the object throughout. The desired
cooling effect may be to promote the destruction and/or the inactivation of
the
surface microorganisms while cooling or freezing the object throughout.
These and other features, aspects, and advantages of the present invention
will become better understood with reference to the following description and
appended claims.
DESCRIPTION
Illustrative embodiments of the invention are described below. While the
invention is susceptible to various modifications and alternative forms,
specific
embodiments thereof are herein described in detail. It should be understood,
however, that the description herein of specific embodiments is not intended
to limit
the invention to the particular forms disclosed, but on the contrary, the
intention is to
cover all modifications, equivalents, and alternatives falling within the
spirit and
scope of the invention as defined by the appended claims.
It will of course be appreciated that in the development of any such actual
embodiment, numerous implementation-specific decisions must be made to achieve
the developer's specific goals, such as compliance with system-related and
business-related constraints, which will vary from one implementation to
another.
Moreover, it will be appreciated that such a development effort might be
complex
and time-consuming, but would nevertheless be a routine undertaking for those
of
ordinary skill in the art having the benefit of this disclosure.
The present invention relates to a cryogenic rapid chilling and sanitation
process in which a mixture of fluid and an additive is used to cold shock an
object.
In one embodiment of the invention the object is subjected to a cooling
process
wherein the object is submerged in the fluid for a time which is regulated to
obtain a
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desired cooling effect, an is subjected to a sanitizing process wherein the
objects are
exposed to one or more primary sanitizing additives either before, during or
after the
cooing process (or any combination thereof). In one embodiment of the
invention,
the liquid cryogen and additive are mixed prior to use in the chilling
process. In this
5 way, both the liquid cryogen and the additive may be directed to the object
simultaneously.
In another embodiment the object may be either food or non-food objects. In
another embodiment of the invention, the additive may be oxidizing agents such
as
ozone, chlorine, chlorine compounds, hydrogen peroxide solutions, oxonia
solutions,
or combinations thereof.
Oxonia is known to one skilled in the art to be a solution composed of either
hydrogen peroxide and peristaltic acid, or hydrogen peroxide and peroxyacetic
acid.
In another embodiment of the invention, the additive may be an organic
substance, an inorganic substance, a combination of two (or more) organic
substances, a combination of two (or more) inorganic substances, or a
combination
of one (or more) organic and one (or more) inorganic substance.
In another embodiment of the invention, the additive may be directed to the
object at a combination of prior to, simultaneous with, or subsequent to the
chilling
process, as desired by the operator. In another embodiment of the invention,
different additives may be directed to the object at differing times in the
chilling
process.
In another embodiment the object may be submerged into the additives one
or more times that are additive prior to, simultaneous with, and/or subsequent
to the
chilling process. In another embodiment of the invention, the object may be
submerged in different additives at different times during the chilling
process.
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In another embodiment of the invention, the rate that the objects are
submerged, and /or the duration of the submergence, in the additive may vary
with
time as a function of the progress of the chilling, or cold shock process.
In another embodiment of the invention, the rate that the objects are
submerged, and /or the duration of the submergence, in the additive may vary
with
discrete locations on the object to be chilled.
In one embodiment of the invention, the regulation of the rate that the
objects
are submerged, and/or the duration of this submergence, may be accomplished by
way of sensors, or weighing devices, or other techniques commonly known in the
industry.
In one embodiment of this invention, the regulation of the rate that the
objects
are submerged, and/or the duration of this submergence, may be accomplished by
way of sensors located on, or within the body of, the object to be cooled.
In another embodiment, the object to be chilled is subsequently introduced to
a chilling room, or a freezing room.
The invention is not limited to the preferred embodiments described above,
but rather defined by the claims set forth below.
