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Description  |
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BACKGROUND OF INVENTION
1. Technical Field
The present disclosure relates generally to the field of pathogen reduction in food processing media, and more particularly to the use of inorganic chloramines as antimicrobial agents in food processing waters used upon food products.
2. Background of the Related Art
Potable water treatment facilities have two primary objectives in controlling pathogens in the public drinking water supply. The first is to eliminate pathogens as part of the water treatment process within the treatment plant and the second is
to provide a residual disinfectant in the finished water to prevent microbial regeneration in the distribution system that carries the water to the consumer.
Because of its efficacy in inactivating a wide range of microbes, chlorination became the standard method for disinfecting potable water in both the water treatment plant and in the distribution system.
However, the reaction of chlorine with naturally occurring organic matter (NOM) in the water can result in the formation of suspected carcinogens such as chloroform, which is in the group of potentially dangerous disinfection byproducts called
trihalomethanes. Growing public health concerns gave rise to the Safe Drinking Water Act Amendments of 1996, which required the U.S. Environmental Protection Agency (EPA) to develop new drinking water regulations, including rules to address
simultaneous compliance of microbial disinfection and disinfection by product generation.
The Disinfection and Disinfection By-products Rules established microbial reduction standards, maximum residual levels for disinfectants and limits for disinfection byproducts such as trihalomethanes (THMs) and haloacetic acids (HAA5). Since
these byproducts are formed by chlorinating certain organic compounds that are typically present in source waters, many drinking water plants were forced to change their methods of disinfection to reduce the formation of these byproducts.
Because of its chemical characteristics, monochloramine, a slow-reacting and persistent anti-microbial agent that is not prone to react with organic matter, gained widespread use in programs designed to meet the new rules. This chlorine species
is generated by the controlled mixing of chlorine and ammonia in water. Currently monochloramine is used primarily to provide a residual biocide in potable water distribution systems. Because of its relatively low antimicrobial efficacy, monochloramine
is not generally used as a primary disinfectant in potable water treatment. The increased usage of monochloramine treatment by municipal water treatment facilities is not because of its disinfection qualities, but rather the change is taking place as
part of a strategy to avoid production of THMs in drinking water.
In his 1967 work, "Aspects of the Quantitative Assessment of Germicidal Efficiency," J. C. Morris presented a tabulation of the concentrations of various germicides required to inactivate 99 percent of the targeted microbes in ten minutes of
contact time. Today this is called specific lethality and is commonly used to compare the biocidal efficacies of chemical oxidizers. At 5.degree. C., the specific lethality of hypochlorous acid (the active agent in typical chlorination process)
was-determined to be at least 200 times that of monochloramine in inactivating enteric bacteria and viruses. Even the hypochlorite ion (the less biocidal component of free chlorine) was determined to have a specific lethality twice that of
monochloramine in inactivating enteric bacteria and four times that of monochloramine in inactivating viruses.
Because of their low specific lethalities, chloramines have been generally disregarded in the search for highly efficacious biocides in the food processing industry. Instead, traditional disinfectants (e.g., chlorine) that have been used and
proven in potable water treatment have generally been adopted for use within food processing.
When an aqueous medium is used as the vehicle to deliver an antimicrobial agent to a food product during processing, the environment in which the antimicrobial agent must perform is significantly different from that of potable water. In typical
potable water the total organic load is a small fraction of what is found in organically laden process water in a food processing plant. Although the effect of the environment (i.e., organic load in the water) on the efficacy of an antimicrobial agent
may have been recognized, there seems to have been an underlying assumption by those skilled in the art that the relative efficacies of the various disinfectants would remain the same in process water with a high organic load as compared to potable
water. This may partially explain the absence of research and general information on the use of what are traditionally considered "weak disinfectants", such as chloramines, in applications that require antimicrobial action in food process waters, on
food products, and in ice that will contact food products.
One example of food process waters that undergo substantial changes during processing that have a marked effect on the efficacy of added antimicrobial agents can be found in a poultry processing plant. Process water in a poultry processing plant
can have extremely high levels of total organic carbon (TOC) and a correspondingly high chemical oxygen demand (COD). Undesirably, any free chlorine added to these high-demand waters rapidly reacts with the organic constituents and is consumed in
seconds, becoming unavailable for disinfection. Monochloramine, which is less reactive and more persistent, remains available to inactivate the microbial population and therefore, under these conditions can be a more effective disinfectant than free
chlorine. It has been found that monochloramine treated process waters produce a nominal one log (10 fold) reduction in pathogen levels over those treated with equivalent concentrations of sodium hypochlorite (free chlorine). In organically laden
water, chloramine disinfection is a more effective disinfecting agent than free chlorine.
A typical poultry processing plant receives live animals from the grow-out farms, slaughters the animals, drains the blood and then removes the feathers, "paws," heads and detritus in the initial stages of processing. The carcasses are then sent
to mechanized evisceration where the internal organs, digestive tract and other edible and inedible parts are removed. In typical operations, some of the internal organs (i.e., heart, liver and gizzards) are harvested for food products. The carcasses
are thereafter sent by way of mechanized line operations through a series of washing and sanitizing steps before the product is shipped as "fresh" product, packaged for freezing or further processed. These line operations typically consume large
quantities of water, the characteristics of which change substantially during the process as organic matter enters the water.
Accordingly, the poultry processing industry has generally been characterized as a large volume consumer of water in conducting the slaughter, processing and packing of animals for both human consumption and other uses. Recent initiatives by the
United States Department of Agriculture (USDA), under the jurisdiction of the Food Safety Inspection Service (FSIS), have resulted in a further increase in the volume of water used to wash poultry carcasses to meet the more stringent requirements of
"zero tolerance" for visual fecal contamination.
In addition, poultry industry interests have been actively seeking methods of reducing the consumption of water due to economic reasons and, additionally in some cases, because of limited availability of sufficient volumes of water to meet the
processing requirements. Still other considerations involving limited water treatment resources have raised the need to reduce water consumption. One illustrative embodiment of the present invention provides additional solutions to reuse process water
and therefore to reducing the volume of water required for processing poultry or other foodstuffs.
Prior food processes have not focused on the need to conserve water from an economic perspective and accordingly, while they may generally involve water reuse applications, their approaches have failed to address critical economic restrictions
inherent in poultry and other food processing operations. It is yet another object of the present invention to provide water reuse processes which are economically feasible and which provide improved savings to the food processing manufacturer.
Typical of prior approaches have been efforts directed to the recovery, treatment and recycling of poultry chiller bath water in a closed loop and "semi-closed loop" type of process where water from the chiller baths is treated to remove solids,
fats, oil, grease, organic compounds and microorganisms before reintroducing the treated water to the chiller baths. These efforts may be characterized as primarily aimed at reducing the electrical power requirements and thereby costs associated with
chilling the water used in these systems of processing operations. These goals are generally met by reusing the already cooled chiller water and trying to reintroduce the already chilled water back into the chiller makeup feed water, thereby reducing
the temperature of incoming fresh water. Unfortunately, the recovery of used chiller bath process water brings with it a very high contamination burden requiring extensive treatment. Representative examples of such approaches have been described in
U.S. Pat. Nos. 5,728,305; 5,173,190; 5,178,755; 5,053,140; 4,790,943; and 5,593,598. Unfortunately, such approaches have had some limited success in addressing the treatment challenges, they have to date proven to be of questionable economic value to
the industry. It is still another object of the present invention to address such deficiencies within the prior art with the use of monochloramine chemistry as well as other approaches and devices, which are economically sensitive.
Prior efforts have also generated a substantial number of devices designed to provide some filtering efforts. U.S. Pat. Nos. 5,759,415; 5,248,439; 5,132,010; 4,876,004; 4,844,189; 4,481,080 and 3,912,533 provide representative examples of
such devices. As will be readily noted, some are structurally complex requiring substantial capital expenses and others, while simpler in structure, are aimed at solving different needs.
For example, U.S. Pat. No. 4,481,080 shows a series of printouts separated by baffles for equalizing the residence times of large and small particles. It has been discovered that such solutions are either unnecessarily complex or are
unnecessary altogether. It is another aspect of the present invention to provide antimicrobial chemistry as well as devices useful in water recovery and treatment methods, which avoid such deficiencies and solve the needs presented by gross levels of
contaminants and other organic matter in process waters.
In several of the above referenced patents their efforts have been directed at chilled water reuse claiming significant savings in BTU requirements. The devices employed have focused upon the recovery, treatment and reuse of the USDA required
0.5 gallon per bird overflow. While the technical approaches may differ from invention to invention, they share the common disadvantages that the source of their water (i.e., bird chiller water) contains a significant and high quantity of organic
contaminants as compared to the sources that are identified by the invention herein, and the volumes available for recovery are limited strictly to the USDA mandated 0.5 gallon per bird limitation. It is yet another object of the present invention to
avoid the disadvantages associated with such prior art approaches.
The chiller in a poultry slaughter process is used to lower the carcass temperature of slaughtered birds and to introduce antimicrobial agents for the purpose of reducing pathogens both in the chiller water and on the poultry carcasses. The
industry standard antimicrobial treatment of poultry chiller water is free chlorine usually delivered in the form of sodium hypochlorite (chlorine bleach). Unfortunately, the use of free chlorine in prior art methods does not reduce pathogens to the
desired levels and creates environmental and workplace hazards including hazardous off-gassing within the plant.
The poultry chiller is a large communal bath where fresh carcasses are constantly being added while chilled carcasses are removed. Depending upon the particular plant, carcasses may remain in the chiller for 1-6 hours. There can be hundreds of
carcasses in the chiller at any point in time. Unfortunately, the potential for cross contamination of carcasses in this communal bath is very high. In an attempt to control the concentration (load) of organic material in the chiller, fresh makeup
water is added which causes the chiller to overflow in an effort to eliminate contaminants. However, the organic loading of water in a typical chiller remains very high in spite of the added water. For example, the chemical oxygen demand (COD) of water
in a typical chiller will often range from 1,000-2,000 parts per million. The challenge of treating this organic load within the water is very difficult and unmet with prior art disinfectants.
USDA FSIS allows the addition of chlorine at levels up to 50 ppm in chiller make-up water. A chlorine demand of 1,000-2,000 ppm cannot be overcome by 50 ppm of free chlorine in the make-up water. Experiments by USDA Western Region ARS concluded
that free chlorine residual could not be established in a chiller even by adding up to 400 ppm of free chlorine.
The most commonly used prior art disinfectants in a food processing plant are highly reactive oxidizing agents. One way of predicting the efficacy of certain disinfectants is by the rapidity with which they can oxidize other substances. Greater
oxidation speeds often cause higher microbial kills. Ozone and chlorine can oxidize very quickly and are widely used as disinfectants. Unfortunately, the very characteristic that normally makes highly reactive oxidants effective disinfectants in
drinking water minimizes their effectiveness in the environment of a poultry chiller or other process water environment having high organic load. The demand for chlorine in chiller water is measured in thousands of parts per million. Being highly
reactive, free chlorine will rapidly oxidize, bleach or combine with any component of the chlorine demand. When chlorine combines with another substance, it ceases to be highly oxidative and loses its ability to bleach.
Because of the virtually inexhaustible demand caused by the organic load within a chiller, when free chlorine is added to the chiller, it remains free and therefore active, for only seconds. Even with relatively high doses of free chlorine, the
contact time with chiller microorganisms is so short, that the Concentration-Time (CT) Value always remains low.
Because of the problems with using free chlorine within the food processing environment, a substantial number of compounds have been explored for use as disinfectant in place of chlorine. For example, U.S. Pat. Nos. 5,437,868, 5,314,687 and
5,200,189 to Oakes et al. are directed to peroxyacetic acid type compounds used as antimicrobials. Another attempt to improve disinfectants within the food industry is set forth in U.S. Pat. Nos. 6,545,047 and 6,103,286 to Gutzmann et al. "Treatment
of Animal Carcasses" which also relates to peroxyacetic acid. Unfortunately these compounds are most effective at low pH, which can be destructive to food processing equipment. There can also be worker safety issues involved in the handling of such
compounds.
Other efforts towards alternative disinfectants have been directed to the use of acidified sodium chlorite as disclosed in U.S. Pat. No. 6,063,425, Kross et al, "Method for Optimizing the Efficacy of Chlorous Acid Disinfecting Sprays for
Poultry and other Meats". Unfortunately the disinfectant that is produced by combining the raw materials (sodium chlorite and acetic acid) is generated at a very low pH (about 2.5) which can be destructive to food processing equipment. Off-gassing,
which can be detrimental to worker health, can also result from the mixing of chlorine and acidified sodium chlorite within the processing plant.
A further disinfectant by Rhodia is directed at using trisodium phosphate (TSP) as disclosed in U.S. Pat. No. 5,882,253, Mostoller, "Apparatus and Method for Cleaning Poultry". Unfortunately there are negative environmental impacts from the
addition of trisodium phosphate to a plant's wastewater since phosphate is a regulated wastewater pollutant. There have also been reports of negative impacts to the quality of poultry treated with this compound.
Despite these various chemistries, they are unfortunately used only for on-line reprocessing and in a few selected cases also in the chiller. They suffer from the disadvantage of only being able to be used at one or possibly two specific points
in the processing line and not throughout the plant. Unfortunately, none of these above disinfectants have been able to replace chlorine throughout the food processing plant.
While biocides that are not highly oxidative may not have the same disinfectant qualities of those that are highly oxidative in pure water, their use within certain environments offers the potential to be far more effective because such biocides
are not as readily consumed by the resident chlorine demand. The less chemically reactive biocide thereby remains active and available to reduce the microbiological populations in the chiller or in other process waters having high organic load. Our
discovery is that a relatively small dose of a less potent but more persistent biocide resulting in a residual presence throughout the chiller or other organically laden process water will out perform its highly oxidative counterpart in reducing the
overall microbial load.
Another area having high organic loading process water within a poultry processing operation is the poultry scalder tank. The scalder tank is one of the very initial steps in the slaughter process and one of the points in which the water is
heavily loaded with organic materials. Water in the scalder has an extremely high organic load, high microbial population and high temperature. The scalder is a communal tank holding numerous carcasses at any point in time, which like the chiller
provides great potential for cross contamination. The conditions in the scalder (i.e., high organic load and high temperature) cause the rapid consumption of free chlorine, which significantly degrades the disinfection potential of the chlorine.
Research has indicated that aeration and boiling of water, characteristics of normal scalder operations, will not destroy monochloramine. This characteristic of monchloramine allows a pathogen reduction step at scalders that is not appreciably
affected by temperature or aeration. It has also been found that monochloramine is more effective than free chlorine for inactivation of biofilm bacteria, as the greater penetrating power of monochloramine more than compensates for its reduced
disinfection activity.
Yet another area of high water use within poultry processing and therefore the need for effective disinfection of water is the evisceration line and various wash cabinets on the processing line. These points of treatment within the evisceration
line are between the scalder at one end and the chiller at the other end of a typical poultry processing plant. USDA regulations allow poultry processors to recondition used process water to specific treatment standards for reuse. While this reuse
water is typically treated to be pathogen free and often has a turbidity level comparable to potable water, the reuse water does have higher levels of soluble organic loading than found in fresh water. Because of this organic loading, any applied free
chlorine will be rapidly consumed, precluding the establishment of an active residual disinfectant. Unfortunately, the lack of an active residual disinfectant will enable bacterial regeneration in water storage and distribution systems.
Advantageously, a chloramine residual can be established in recycled water that is rich with organics. This residual can then be used both to reduce the potential for bacterial regeneration and to subsequently help disinfect whatever the
recycled water contacts. The inventive method therefore broadens the potential applicability of water reuse systems within poultry processing plants. With chloramine treatment, the quality of disinfected recycled water can be effectively maintained and
the water itself can be used as a vehicle to deliver an effective anti-microbial agent. The inventive method therefore enhances the economic viability and effectiveness or water reuse systems within poultry processing and other food processing systems.
The stable active residual provided by monochloramine and its enhanced ability to penetrate bacterial cell walls provides consistent pathogen reduction on equipment used in a poultry processing plant.
It is contemplated within the scope of this invention that chloramination can be universally applicable to the treatment of food processing waters and the manufacture of ice independent from or in conjunction with any or all steps described
herein regarding the treatment of process waters for reuse.
SUMMARY
In one particular illustrative embodiment in accordance with the principles of the present disclosure, the inventive approach of the present invention includes processes which allow for the safe and economic recovery, treatment and reuse of
certain poultry processing water, specifically including the "carcass final rinse," "inside/outside carcass rinse," "water rails", water sprays used in the inspection process, scalders, instruments, flume transport of various animal parts, water from the
communal chiller bath and other smaller streams with respect to poultry processing operations and other food processing applications, like red meat washing, fruit and vegetable washing, retort cookers and pasteurizers.
The present disclosure contemplates implementing a water reuse program that returns disinfected reuse water to which chloramines have been added at an advantageous dosage before being reintroduced to the production process at an upstream point,
such as in the scalder or similar heating portion of the processing steps. The reintroduction of the chloraminated reuse water into the scalder or similar heating processing step advantageously causes a dramatic reduction in the levels of microorganisms
associated with the carcasses that have not been found in the prior art.
The inventive method further contemplates introducing chloramine treated water, for example, along the foodstuffs processing steps, such as along the points where the use of heated water is applicable, such as in the scalder or similar processing
steps which subject the carcasses or food product to heated water. In such heated processing steps, the pores and tissue membranes of the carcasses are open and are more readily receiving of the surrounding water, i.e., the chloraminated water, thereby
having greater efficacy to the removal of microorganisms associated with such foodstuff processing.
It is contemplated within the scope of the invention that in certain circumstances chiller bath overflow water may be used as one of the water sources for reuse if such chiller water can be sufficiently diluted with water from other sources.
According to the invention, the intended points of re-use for this recovered and treated water have been identified to include chiller bath water, evisceration wash water, defeathering water and other "non-product contact" processes. Additionally, in
those plants where transport of process water is complicated due to plant layout and physical design an improved device is provided for effecting an economic and efficient recovery system comprising a recovery sump with a continuing overflow to permit
reconditioning through the removal of soiled water, grease and oils.
In an alternate illustrative embodiment, the present disclosure employs an approach which focuses on appropriately regulating and controlling the pH of process water to be disinfected through addition, regulation and control of a disinfecting
agent. The control of pH and level of disinfecting agent is implemented throughout multiple steps in the production process including any process water to be recovered and reused. This is in contrast to prior approaches which have failed to appreciate
the benefits associated with pH control, multiple point controlled treatment, or even the unexpected advantages to be gained by reducing the organic loads within such process water.
The poultry process treatment water which can especially benefit includes water used in poultry scalding, picking, post-pick washing, evisceration, carcass washing and other stages of poultry processing designed to physically remove any fecal
matter, ingesta and other digestive tract remnants from the slaughter and evisceration processes. Additionally, an improved device and method are provided for effecting economic and efficient regulation of chloramines disinfection agent and control of
chloramines disinfection chemistry throughout the multiple steps of the production process.
Physical removal of visible fecal material and other contaminants from poultry carcasses will be carried out by serial carcass washing steps (e.g., scalder, picker, post pick spray wash, inside/outside carcass washing cabinets and outside carcass
washing cabinets) where medium pressure, high volume water spraying is employed. The controlled introduction of chloramines according to the invention can be applied at multiple treatment stages (e.g., scalder, picker, post pick spray wash,
inside/outside carcass wash and outside carcass wash) and using the best practical control methods is designed to significantly reduce microbial levels on all carcasses prior to and after their entry into the immersion chiller system.
Aspects of the invention include the benefits of adding chloramines to poultry chiller water together with the effectiveness of increased concentration time (CT) through the implementation of multiple stage treatment of the carcass during
slaughter, evisceration, washing and chilling.
According to the invention, combining a chlorine source with a known amount of ammonia produces chloramines. The use of monochloramine, as opposed to the other constituents of total combined chlorine, reduces the risk of chlorine off gassing
from the chiller or other points within the plant and thereby preventing worker safety hazards and producing a reduction in pathogens to a desired level.
Additionally, the present disclosure provides for effecting economic and efficient regulation of disinfection agent effectiveness comprising a system and method for removing a major portion of filterable materials including fats, oils and greases
(FOG), total suspended solids (TSS), proteins, blood products, lipids and other materials represented as total chemical oxygen demand (COD) from the chiller tank water.
Aspects of the presently disclosed disinfection process for use in the processing of foodstuffs are designed as an intervention step in poultry processing to allow for continuous on-line reprocessing of poultry carcasses that may have
accidentally become contaminated during the evisceration process. Such on-line reprocessing is designed to replace the need for off-line manual washing and cleaning of the contaminated carcasses. By eliminating such off-line manual washing, food safety
will be enhanced due to the elimination of the physical handling of carcasses and the cross-contamination that may result from such physical handling. An additional benefit is that it will be possible to run the production process with a reduced number
of interruptions, which will result in a more efficient production process that will produce increased yields.
The disinfection process according to the present invention can include: the removal, using the processing plant's existing washing, spraying and mechanical scrubbing devices (modified if required), of visible fecal material or other contaminants
from the carcasses resulting from the mechanical evisceration process; the controlled introduction of chloramines at multiple stages to improve food safety by reduction of total microbial levels; the improvement of disinfection in the facility's overall
production process including the carcass chiller system through the use of chloramine disinfectant techniques to further reduce microbial counts, and the reduction of the amount of physical handling of carcasses and therefore, reduction of the potential
for cross-contamination through the implementation of continuous on-line processing of poultry carcasses that may accidentally become contaminated during the evisceration process.
Further, the present invention is specifically designed to be easily incorporated into the processor's existing production equipment and plant layout. This ease of implementation is accomplished by using, to the greatest extent possible, the
processor's existing carcass wash stations, scalders, pickers and other designated treatment points as the point of treatment by using the existing water piping and delivery systems as the means of delivery of the invention's chemical and disinfection
enhancements.
While the introduction of chloramines may be accomplished using standard spray equipment in the processor's existing carcass washing stations alternative spraying mechanisms and/or treatment stations may be used to address specific needs. In an
alternative embodiment of the present invention, the chloramine solution spray can comprise a fogged material utilizing available fogging apparatus that leaves a dispersion of fog particles in a continuous atmosphere to envelope the carcass.
In another alternative embodiment of the present invention, the carcasses may be treated with an electrostatically charged spray of the chloramine solution. In this embodiment, the chloramine solution can be applied as charged droplets by using
conventional electrostatic spray technologies. Surfaces such as walls, conveyor belts and equipment carry a natural positive charge, as do animals such as chicken carcasses. When high-pressure air and a chloramine solution are forced through a small
aperture in the electrostatic spray nozzle, the air shears the sanitizer into tiny droplets. These droplets are then exposed to an electrical charge as they exit the nozzle head. This transfers a negative charge to the drops of chloramine solution,
which then have a particular affinity for the surfaces in the area, such as equipment, chicken carcasses or other foodstuffs. The charged droplets provide an evenly distributed solution layer on the treated surface. Because the deposition of sanitizer
on the surface being treated is so much more efficient, significantly less sanitizer is required to achieve the same bacterial disinfection rate when compared to common commercial sprayers. Many sanitizers, especially those that are highly oxidative,
cannot be used with electrostatic sprayers, since the electrical charge can completely eliminate their killing power before they reach the targeted surface.
In yet another alternative embodiment of the present invention, surfaces may be treated with a chloramine solution in a foam formulation that would adhere to surfaces for a longer period of time than the liquid alone. This would increase the
contact time on the treated surface thereby increasing the CT (Concentration-Time) value and overall efficacy of the antimicrobial treatment.
The invention described herein is designed to meet the current USDA regulations for removal of visible fecal material using the plant's existing washing, spraying and mechanical scrubbing devices, and to reduce microorganism counts and improve
food safety, all in a more cost effective, safer and environmentally friendly manner than other approaches.
BRIEF DESCRIPTION OF THE DRAWINGS
The foregoing and other features and advantages of the present invention will be more fully understood from the following detailed description of illustrative embodiments, taken in conjunction with the accompanying drawing in which:
FIG. 1 is a top plan view illustrating one particular embodiment of a recovery sump device, in accordance with the present disclosure;
FIG. 2 is a side cross-sectional view illustrating the recovery sump device shown in FIG. 1, in accordance with the present disclosure;
FIG. 3 illustrates an overall flow chart of one particular embodiment of a water recovery system, in accordance with the present disclosure;
FIG. 4 illustrates an alternate embodiment of a detailed operative engaging flow plan;
FIG. 5 illustrates a flow chart of another embodiment of the water recovery system according to the present disclosure;
FIG. 6 is a graphical representation of the average reduction in salmonella on chicken carcasses due to chiller treatment using the invention method;
FIG. 7 is a graphical representation of the average reduction in e.coli on chicken carcasses due to chiller treatment using the inventive method;
FIG. 8 is a graphical representation of the average reduction in pseudomonas flourescens on chicken carcasses due to chiller treatment using the inventive method;
FIG. 9 is a schematic illustrating a methodology to manufacture and inject chloramines;
DETAILED DESCRIPTION OF THE INVENTION
The illustrative embodiments of the apparatus and methods disclosed herein are discussed in terms of poultry processing water disinfection processes and in particular chicken processing plants. It is contemplated within the scope of the
invention, however, that the disclosure is applicable to a wide variety of food processes including, but not limited to general carcass processing in the poultry industry along with carcass, parts and trim processing in the beef and pork and seafood
industries along with bulk food processing within the produce industry. It is contemplated within the scope of the invention that the inventive method may be used within any food processing system where it is desirable to reduce pathogen via aqueous
medium used within the processing methods.
The inventive method, of using chloramines for pathogen reduction is also applicable to water reclamation and reuse applications in which organic loads are higher than that normally encountered in potable water and which require a persistent
antimicrobial residual in the finished water.
The inventive method is also envisioned to be applicable to extending the shelf life of food products by treatment with chloraminated process waters and/or a dedicated final chloramine spray or dip prior to packaging. The persistence of the
chloramine will continue to provide antimicrobial action after packaging, increasing the safety of the product to the consumer as well as extending the useful life of the product.
It is further envisioned that the treatment and chloramination processes described in the present disclosure are applicable to the making ice intended to both cool food products and to provide an antimicrobial agent to water and food products in
direct contact. The following discussion includes an explanation of relevant terminology, a description of instrumentation employed for poultry processing and water disinfection, in accordance with the present disclosure, followed by a description of
the preferred processes associated therewith.
A poultry processing line includes multiple processing steps. One step involves a poultry carcass being immersed in a chiller tank and is referred to as the "chilling step." During the chilling step, temperature of the poultry carcass is cooled
as a result of immersion in a cold water bath. The "chilling step" is significantly different from other processing steps such as scalding, picking, evisceration, and various washing steps. These steps are referred to as "non-chilling processing
steps."
Water in the chiller tank is significantly different from water in the various non-chilling steps in terms of organic loading and temperature. The poultry carcass is placed in the chiller tank in an effort to cool the carcass to a temperature
which inhibits the growth of pathogens. Carcasses entering the chiller tank may be as warm as 100 .degree. F. and exit at approximately 34-38.degree. F.
The chiller tank is a communal tank that can hold hundreds of poultry carcasses for 1-6 hours, or longer. A required volume of makeup water, based on the number of carcasses processed, is added to the chiller tank resulting in overflow from the
chiller tank. The water in the chiller tank has an extremely high organic load of both | | |
