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.
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.
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 fluid, 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 know 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.
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.
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 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 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 know 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.
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.
This application claims the benefit of U.S. Provisional Application No. 60/519,679, filed Nov. 12, 2003, the entire contents of which are incorporated herein by reference.
Number | Date | Country | |
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60519679 | Nov 2003 | US |