Patent Publication Number: US-2007110860-A1

Title: Food surface sanitation tunnel

Description:
BACKGROUND OF INVENTION  
      1. Field of the Invention  
      The present invention relates to the simultaneous sanitation of several food surfaces and more particularly pertains to industrial modular, compact, efficient systems and devices for sanitizing foods during processing and packaging, especially those processed on assembly lines. The present invention also relates to foods sanitized by such systems and devices.  
      2. Description of Related Art  
      Food sanitation is a growing concern in the world. More and more aggressive disease-causing agents are discovered every year. In addition, an increasing number of people are made ill each year by eating contaminated foods. Also, the numbers of foods linked to food-caused illnesses continues to increase. Nonetheless, the desire for safer foods is higher than ever. In fact, more and more state and federal jurisdictions are requiring that businesses use the most efficacious food safety and sanitation practices.  
      Efficient use of modern sanitization techniques decreases the cost of applying them. These savings, when passed to the consumer, mean the consumers spend less on the processed foods. Also, efficient sanitizing techniques can allow more food to be processed in a smaller amount of space. Thus, smaller facilities may compete with larger ones, thereby increasing competition between processors and lowering prices to consumers. In addition, facilities that use less-safe processing techniques may be easily retrofit to install an efficient apparatus. Furthermore, modularity in a sanitizing system or device makes it easy to manufacture and easy to replace parts.  
      Sanitizing radiation allows a highly controllable application of organism-killing radiation to foods and food additives. The use of sanitizing radiation in the food industry in general is well known in the prior art, and has been used in a variety of forms, including gamma ray radiation, ultraviolet (UV) light and infrared radiation.  
      For example, it is well known that gamma radiation and UV radiation has been used in some countries for the sterilization of spices and animal feeds. However, over-use of ultraviolet radiation may cause undesirable chemical reactions with a food or food additive, which can cause the food or food additive to obtain undesirable flavors or textures. Also, various vitamins and proteins may be altered or destroyed through being subjected to too much radiation, reducing the food value of the treated product.  
      Traditional methods of irradiating foods processed or packaged in assembly line manner use an unnecessary amount of radiation, as well as space, in a food processing facility. Furthermore, they fail to take full advantage of the combined use of ozone, UV light, hydroperoxides, superoxides and hydroxyl radicals in the sanitization process. For example, U.S. Pat. No. 6,150,663 to Rosenthal teaches a system incorporating an irradiation system using radiation, and only radiation, to sanitize food. Rosenthal also teaches vibration of the food to optimize radiation exposure to all of the food surfaces. The entire system is inefficient and ineffective, as irradiation alone may not properly sanitize food, and there is no sanitization of more than one side at the same time. In addition, if there were a slight fold on the food surface, the shaded food surface would never be sanitized. However, ozone, hydroperoxides, superoxides and hydroxyl radical ions are able to get beneath a fold and sanitize a folded over food surface. Furthermore, hydroperoxides, superoxides, ozone and hydroxyl radical ions, when used together, reduce the amount of radiation needed thereby decreasing radiation damage to food. Also, if the food were prepackaged so that vibration would topple the packaging, then the Rosenthal process would be contraindicated.  
      Thus, there is a need for a portable modular system that sanitizes more than one food surface simultaneously. There is also a need for a system that uses the sanitizing combination of radiation, ozone, hydroperoxides, superoxides and hydroxyl radicals, or one that makes it easy to apply or manufacture economically. There is also a lack of such a sanitizing system that may be retrofit into an existing assembly system. There is no system designed with modularity in mind, to suit different processes properly, or to provide easy manufacture or replacement of component parts. There is no system wherein the radiation, ozone, hydroperoxides, superoxides and hydroxyl radicals are optimized for food treatment. There is no system that efficiently utilizes sanitizing radiation, ozone, hydroperoxides, superoxides and hydroxyl radicals to sanitize processed and/or prepackaged foods. There is no system which adds regulated amounts of moisture to the enclosing sanitizing system to improve the efficiency of the formation of hydroperoxides, superoxides and hydroxyl radicals in sanitizing food. There is no such. system that is easy to assemble, adjust, transport, clean, maintain and disassemble. There is no system using sanitizing radiation, ozone, hydroperoxides, superoxides and hydroxyl radicals that is adjustable on a frame with wheels, or that uses sanitizers on more than one side simultaneously. In other words, there is no system that takes advantage of the sanitizing and free-moving characteristics of a combination of radiation with ozone, hydroperoxides, superoxides and hydroxyl radicals to improve sanitization beyond what mere radiation can perform.  
     SUMMARY OF INVENTION  
      The present invention is a modular, adjustable, portable, easy to maintain food sanitation tunnel system, having an enclosing means for simultaneously subjecting food on at least two sides to sanitizers including UV light, ozone, and plasma including hydroperoxides, superoxides and hydroxyl radicals. The enclosing means has one or more UV light sources and one or more target rods in optical proximity to the UV light sources. The UV radiation sources emit UV light of approximately 185 to 254 nm. In an alternative embodiment, the enclosing means further comprises drainage holes through a bottom surface.  
      In another embodiment, the target rods comprise up to approximately 0-30% titanium dioxide, up to 0-30% silver and up to 0-30% copper, by weight. In yet another embodiment, the system includes a mister for adding an optimized amount of mist in proximity to the target rods for the efficient production of hydroxyl radicals. In still another embodiment, hydroxyl radicals are generated in part from the moisture in the ambient air in the proximity of the target rods.  
      In yet another embodiment, a door at least partially encircles the food within a space defined by the enclosing means. The door is removably attached to an overhang of the enclosing means. In still another embodiment, the system includes an electrical box attached to the exterior of the enclosing means, and the electrical box has a removable cover plate.  
      In another embodiment, the enclosing means is C-shaped. In yet another embodiment, the system has alternating UV light sources and target rods. In still another embodiment, the enclosing means is approximately 46 inches in width. In yet still another embodiment, the target rods are of modular construction.  
      In yet another embodiment, the UV light source is located within an assembly. In another embodiment, the assembly includes a reflector tube and a shield, and the assembly is of modular construction. In still another embodiment, the target rods and the assemblies are easy to manufacture, maintain and replace.  
      In yet still another embodiment, the system includes a rigid frame for the enclosing means, and a self-contained adjustable conveyor. In another embodiment, the system includes a ballast housing and a control box located on the frame, and the frame has wheels.  
      In yet another embodiment, the UV light sources and the target rods surround the food in a rectangular or triangular shape. In still another embodiment, the frame is adaptable to allow the enclosing means to be optimally located in relation to the food.  
      In still another embodiment, the invention is a food sanitation tunnel, comprising means for subjecting food to sanitizing radiation, means for subjecting food to ozone and means for subjecting food to a sanitizing plasma, whereby the food is subjected to the radiation, the ozone and the plasma generally simultaneously. In yet another embodiment, the means for subjecting food to sanitizing radiation, the means for subjecting food to ozone and the means for subjecting food to sanitizing plasma includes one or more sanitizing radiation sources located in an assembly and one or more target rods in optical proximity to the assemblies. In yet still another embodiment, the assemblies and the target rods are modular in construction, easy-to-clean and easy-to-maintain. In addition, the tunnel is generally portable. The assemblies and target rods are in generally triangular orientation, a c-shaped configuration, or other preferred orientation.  
      In still another embodiment, the tunnel includes an enclosing structure, and a door is removably attached to an upper portion of the enclosing structure.  
      In yet another embodiment, the invention is a method for sanitizing food comprising the exposing of a food surface within an enclosure simultaneously to UV light, ozone, and sanitizing plasma. In another embodiment, the invention is the food sanitized by the method above.  
      It is an object of this invention to provide a portable modular system that sanitizes more than one side of a food surface simultaneously.  
      It is another object of this invention to provide a modular system makes utilization of the sanitizing combination of radiation, ozone, hydroperoxide, superoxide and hydroxyl radicals easy to apply or manufacture economically, or to fit into an existing system.  
      It is still another object of the invention to provide a system designed with modularity in mind, and to provide easy manufacture or replacement of component parts.  
      It is yet another object of the invention to provide a system wherein the radiation, ozone, hydroperoxide, superoxide and hydroxyl radicals are combined and optimized for food treatment.  
      It is yet still another object of the invention to provide a system that efficiently utilizes sanitizing radiation, ozone, hydroperoxide, superoxide and hydroxyl radicals to sanitize processed and/or prepackaged foods during processing and packaging.  
      It is still another object of the invention to provide a system which adds moisture to the sanitizing system to improve the efficiency of the formation of a sanitizing plasma for sanitizing food.  
      It is yet another object of the invention to provide a system that is easy to assemble, adjust, transport, clean, maintain and disassemble.  
      It is still another object of the invention to provide a system using sanitizing radiation, ozone, hydroperoxide, superoxide and hydroxyl radicals that is adjustable on a frame.  
      It is yet still another object of the invention to provide a system that takes advantage of the sanitizing and free-moving characteristics of the combination of sanitizing radiation, ozone, hydroperoxide, superoxide and hydroxyl radicals to improve sanitization beyond what mere radiation can perform.  
      In accordance with these and other objects which will become apparent hereinafter, the instant invention will now be described with particular reference to the accompanying drawings. 
    
    
     BRIEF DESCRIPTION OF DRAWINGS  
       FIG. 1  is a front perspective view of the preferred embodiment of the invention.  
       FIG. 2  is a cut away top view of the preferred embodiment of the invention, revealing the UV light sources.  
       FIG. 3  is a front elevation view of the preferred embodiment of the invention, without the optional door.  
       FIG. 4  is a side elevation view of the preferred embodiment of the invention.  
       FIG. 5  is a side elevation view of a UV light source of the invention.  
       FIG. 6A  is a side elevation view of a reflecting tube of the invention.  
       FIG. 6B  is an end elevation view of a reflecting tube of the invention.  
       FIG. 7  is a side elevation view of a shield of the invention.  
       FIG. 8  is a side elevation view of a UV light assembly of the invention.  
       FIG. 9  is a side elevation view of the shell of the invention.  
       FIG. 10  is a top plan view of the top section of the shell of the invention.  
       FIG. 11  is a top plan view of the bottom section of the shell of the invention.  
       FIG. 12  is a top plan view of the side section of the shell of the invention.  
       FIG. 13A  is a perspective view of the center box of the invention.  
       FIG. 13B  is a side elevation view of the center box of the invention.  
       FIG. 13C  is an end elevation view of the center box of the invention.  
       FIG. 14A  is a side elevation view of a door for the shell of the invention.  
       FIG. 14B  is a front elevation view of a door for the shell of the invention.  
       FIG. 15  is a side elevation view of an endpiece for the shell of the invention.  
       FIG. 16  is a side elevation view of a cover plate for the top and bottom concave portions of the center box of the invention.  
       FIG. 17  is a side elevation view of a cover plate for the side concave portion of the center box of the invention.  
       FIG. 18A  is a top plan view of a frame for the invention.  
       FIG. 18B  is a side elevation view of a frame for the invention.  
       FIG. 18C  is an end elevation view of a frame for the invention.  
       FIG. 19  is a front elevation view of the mister used in an alternative embodiment of the invention.  
       FIG. 20  is a side elevation view of the mister used in an alternative embodiment of the invention.  
       FIG. 21  is a detailed view of the mist header used in an alternative embodiment of the invention. 
    
    
     DETAILED DESCRIPTION  
      The present invention is a modular, adjustable, portable, easy to maintain food sanitation tunnel system, shown generally in  FIGS. 1-4  at  10 . The system includes an enclosing means of a predetermined geometry, such as a c-shaped tunnel  12  for simultaneously subjecting food on at least two sides to sanitizers including UV light, ozone, and a sanitizing plasma including hydroperoxides, superoxides and hydroxyl radicals. Attached to the inside surface of the tunnel  12  are one or more sanitizing radiation sources, such as UV light sources  14 , and one or more target rods  16  that are located within the tunnel  12  in optical proximity to the UV light sources  14 .  
      Preferably the tunnel  12  is made from a rigid, food safe material, such as stainless steel. The tunnel  12  is placed around the food to be sanitized, so that sanitizers touch the food on at least two sides. It is preferred that the food is passed through the tunnel  12  along a conveyor. Where sanitization of the food comes from below the conveyor, it is preferred that the conveyor allow the sanitizers to pass through the conveyor. For example, the conveyor may be a mesh or webbing, or be at least translucent to ionizing radiation, or both.  
      The sanitizing radiation sources are preferably generally cylindrical UV light sources  14 , such as low vapor mercury lamps that emit UV light of approximately 185 to 254 nm. However, other sanitizing radiation sources such as medium or high vapor mercury lamps may be used. Thus, both high energy and medium to low energy UV light is preferably used. It is also preferred that the UV light source  14  have its electrical connectors  18  on one end rather than on both ends of the UV lamps  14 , as shown in  FIGS. 5 and 8 . This configuration facilitates cleaning of the system  10 , the use of protective conduits for wiring throughout the system, and replacement of the UV light sources.  14 . However, other sanitizing radiation sources in other configurations may be used.  
      Also, in the preferred embodiment, the UV light source  14  is located within an assembly  20 , as shown in  FIGS. 1-3  and  8 . The assembly  20  makes replacement of the UV light sources  14  easier, acts as a barrier to protect both the UV light source  14  and the food it sanitizes, and reflects UV light to make the UV light source  14  a more efficient sanitizer. The assembly  20  is preferably made as described below.  
      Around the UV light source  14  is preferably a generally cylindrical reflector tube  22 , as shown in  FIGS. 6A, 6B  and  8 . The tube  22  has a highly reflective interior surface, so the UV light from the UV light source  14  is reflected onto the food and the vicinity of the target rod  18 . Also, it is preferred that the tube  22  be rigid to help in securing the connection of the UV light source  14  onto the interior of the tunnel  12 . The reflector tube  22  is positioned so that at least some UV light that would otherwise be emitted by the UV light source  14  in a direction away from the food is redirected generally toward the target rod  18 , the air around the food, or the food itself, to optimize the sanitization process. It is also preferred that the reflector tube  22  is of a shape designed so that the UV light source&#39;s radiation is not obstructed. In addition, the interior geometry of the reflector tube  22  may be altered to optimize reflection of the UV light onto the target rod  18 , the air around the food, or the food itself. The preferred material for the tube  22  is aluminum; however, other metals may be used, or a reflective coating may be placed on the interior surface of a rigid, generally cylindrical piece.  
      Around the UV light source  14  and the reflector tube  22 , fused, is preferably a shield  24 , shown in  FIGS. 7 and 8 . The shield  24  protects the food from any material that may possibly fall into the food if the UV light source  14  breaks. Preferably, the shield  24  is a transparent, generally flexible cylinder made from fluorocarbon. However, other equivalent materials may be used.  
      In the preferred embodiment, as shown in  FIG. 8 , on each end of the shield  24  is an endcap fitting  26 . Each endcap fitting  26  is generally cylindrical and allows each end of the shield  24  to fit at least partway within it. Around each endcap fitting  26  is a means for forming a compressive seal, such as a gasket  28 . On the far end of each endcap fitting  26  is either a closed endcap  30  or an open endcap  32 . These endcaps are illustrated in  FIGS. 1-4  and  8 . A closed endcap  30  is preferred for the end of the UV light source  14  that has no electrical connectors  18  to protect the UV light source  14  and is preferably opaque to reduce radiation escaping from the tunnel  12 . An open endcap  32  is preferred for the end of the UV light source  14  that has electrical connectors  18  to provide access to wiring and electronics for the UV light sources  14 . In the preferred embodiment, the endcap fittings  26  and the endcaps  30 ,  32  have complementary threads, so that screwing the endcaps  30 ,  32  onto the endcap fittings  26  compresses the compressive seal.  
      The compressive seal around the assembly  20  helps keep the UV light within the tunnel  12 , and protects the assembly  20  from the outside environment. The rigid reflector tube  22  are preferred to be sufficiently rigid to help provide resistance for screwing the endcaps  30 ,  32  onto the endcap fittings  26  in forming the compressive seal. The reflector tube  22  also forms a support for the shield  24  so that the shield  24  does not contact the UV light source  14  during maintenance and cause the UV light source  14  to break.  
      Shown in  FIGS. 1,4 , in optical proximity to the UV light sources  14  and attached to the inner surface of the tunnel  12  is at least one generally cylindrical target rod  16 . The target rods  16  are generally parallel to the UV light sources  14 . The target rod  16  preferably comprises up to approximately up to 0-30% titanium dioxide, up to 0-30% silver and up to 0-30% copper, by weight, and attached to a stainless steel substrate. The number of target rods  16  and UV light sources  14  is dependent upon the amount of sanitization desired as well as the size of the area to be sanitized. As shown in  FIGS. 1-4 , the target rods  16  are offset and evenly interspersed between the UV light sources  14 . However, other geometry may be preferred for different sanitization processes, so long as sufficient UV light reaches the target rods  16  to help form the sanitizing plasma.  
      As shown in  FIGS. 1-4 , target rods  16  are placed within the interior portion of the tunnel  12 , and are held in place by endcaps  34 . Thus, the target rods  16  are like the UV light assemblies  20 , in that both are modular and easily accessible for replacement or maintenance. However, both the UV light assemblies  20  and the target rods  16  alternatively may be hung or secured onto the interior of the tunnel  12  by means not including any endcaps.  
      The UV light source itself helps sanitize the food. The UV light also interacts with oxygen to form ozone, which also helps sanitize the food. Moreover, the UV light also interacts with moisture and the target rod  16  to form hydroxyl radicals, superoxides and hyperoxides in a plasma that helps sanitize the food. The UV light generally helps to increase the amount of hydroxyl radicals, superoxides and hydroperoxides. Moisture for use with the target rods  16  may exist naturally in the area of the tunnel  12 .  
      Alternatively, moisture may be added by a separate mister  100 , shown in  FIGS. 19 and 20 , either attached to or in proximity to the tunnel  12 . The mister is preferably mounted onto the tunnel  12  with a mounting bracket  102 , although it may be situated so that it applies mist toward the food without being attached to the tunnel  12 . Water is preferably excited by an ultrasonic mist former  104 . The mister  100  also preferably includes mist eliminator  106  mesh means for eliminating mist between the means for moving air onto the food, (such as a fan  108 ) and the reservoir  110  of water. The output of the fan  108  can be regulated with a flow controller  120 . The level of the reservoir  110  is preferably regulated by a float valve  112 . It is preferred that the material for the mist eliminator  106  is polypropylene or an equivalent material. The mist flows from a flexible tube  122  or equivalent means to a mist outlet  114  The mist outlet  114  means for controlling the amount of mist applied toward the food is also preferred. As detailed in  FIG. 21 , it is located on a mist header  116 . Also, an adjustable vent block  118  is used in conjunction with a mist header  116  to control the amount of mist emitted.  
      As shown in  FIGS. 1 and 9 , in the preferred embodiment, the tunnel  12  comprises a shell  36 , preferably made of an easy to maintain rigid material, such as stainless steel. The shell  36  includes a top portion  38 , a bottom portion  40  and a side portion  42 .  
      Preferably the top portion  38 , bottom portion  40  and side portion  42  are separately manufactured in pieces as shown in  FIGS. 10-12 , respectively. The portions  38 ,  40 ,  42  are then joined together, either permanently or temporarily. The preferred method of attachment is welding. In addition, as shown in  FIG. 11 , one or more drain holes  43  are drilled through the bottom portion  40 , for any fluids that may drip from the food. It is preferred that the drain holes  43  are approximately one inch in diameter.  
      In an alternative embodiment, as shown in  FIGS. 14A and 14B , a door  48  is attached to the front side of the top portion  38  of the shell  36 . The door  48  may be removably or permanently attached. Moreover, the door  48  may be hingeably attached or removable from the shell  36 . To facilitate attachment of a door  48 , the top portion  40  of the shell  36  may further comprise a lip  50 , so that the door  48  may hang from it by a complementary flange  52 . The door would be superfluous where UV light sources  14  and target rods  16  surround the food.  
      Attached to the top, bottom, and side portions  38 ,  40 ,  42  of the shell  36  are means for attaching the UV light sources  14  and target rods  16  to the shell  36  of the tunnel  12 . In the preferred embodiment, as shown in  FIGS. 2 and 3 , at least one center box  46  and end pieces  54  are attached to the top, bottom and side portions  38 ,  40 ,  42  of the shell  36 . The center box  46  is a generally c-shaped member shown generally in  FIGS. 13A-13C . It is preferably made from a rigid material, such as stainless steel. It is also preferred that the center box  46  is attached to the shell  36  by welding; however, other means such as screws or rivets may be used. As shown in  FIG. 13A , the back of the center box  46  preferably includes a concave section  56 . Support holes  58  for supporting the UV light sources  14  and their assemblies  20  are drilled through the concave section  56 . Thus, the concave section  56  may serve as a conduit for wiring and electronics for the UV light sources  14 . The holes  58  are preferred to be complementary to the endcap fitting  26  and the open endcap  28  for an assembly  20 , so the assemblies are held in place. In addition, voids  60  for accommodating the target rods  16  are also drilled through the center box  46 . The rods  16  are preferably held in place by having the target rod endcap  34  located on the concave portion  56  of the center box  46 .  
      Endpieces  54 , as shown in  FIG. 15 , are also preferably attached to the top, middle, and bottom portions  38 ,  40 ,  42  of the shell  36  by welding. Holes  58  in each endpiece  54  also help support the UV light sources  14  and the associated assemblies  20 . Similarly, voids  60  are drilled through each of the endpieces  54  for supporting target rods  16  by the target rod endcaps  34 . Thus, a target rod  16  and an assembly  20  are supported by both the center box  46  and an endpiece  54 . In an alternative embodiment, a plurality of center boxes  46  may be used within an enlarged shell, and UV light sources  14  and target rods  16  may be supported by two serial center boxes  46 , as well as a center box  46  and an end piece  54 .  
      It is also preferred that a top and bottom cover plate  62  and a side cover plate  64 , as shown in  FIGS. 16 and 17 , are used to help protect elements within the concave portions  56  of the center box  46 , such as wiring and other components. The cover plates  62 ,  64  are preferably removably attached by screws inserted in screw holes  66 ,  68  through the cover plates  62 ,  64  and in holes  70  through each portion of the shell  36 , as shown in  FIGS. 10-12 . However, other attachment means, such as rivets or welding, are contemplated. Wiring and other electronics may run through holes in one or more cover plates.  
      In one embodiment, shown in  FIGS. 1-4 , the shell  36  is attached to the upper portion of a rigid frame  72 . The frame  72  alone is separately shown in  FIGS. 18A-8C . The tunnel  12  is preferably adjustable vertically and horizontally in relation to the frame  72  to optimize sanitation of the food. Adjustment may be made hydraulically, electronically, or mechanically or by other equivalent means.  
      It is also preferred that the frame  72  includes one or more generally impermeable but easily accessible control boxes  74 , shown in  FIGS. 1-4 . The control box  74  preferably has one or more removable cover panels  76  for access to the circuitry, and an on-off switch  78 . Also, the control box  74  may include a lamp indicator light  82  to show whether power is being sent to the system  10 . It is preferred that the frame  72  and cover panels  76  to the control box  74  and ballast housing are made of an easily cleanable material, such as stainless steel or aluminum.  
      In an alternative embodiment, the frame  72  is housed on wheels  80 . Preferably, the wheels  80  are able to lock into position so the system  10  is portable yet fixable in a predetermined place.  
      In addition, while a c-shaped system  10  has been illustrated, other geometries are contemplated. For example, the elements contributing to the sanitization of the system  10  may be circular or triangular in orientation. Moreover, a full rectangular orientation of the elements may be used that does not require any door.  
      The apparatus sanitized food in accordance with the following procedure.  
      The food passes through the tunnel. The apparatus uses means for treating the food with UV light including UV-C light. Also, the apparatus treats the air around the food with UV light including UV-C light in the presence of a target to form a first set of chemical species. The apparatus then treats the products of the treated air in the presence of air with UV light including UV-C light to form a second set of chemical species. The first set of chemical species includes ozone, superoxides, and hydroxide radicals. The second set of chemical species includes hydroperoxides. The air to be treated usually includes latent water. However, water may be added to the air being treated by a mister to improve the performance of the apparatus.  
      In operation, a zone of plasma is created between the target and the UV light. The plasma includes air having hydroxyl radicals, ozone, hydroperoxides and super-oxides. Part of the reason the apparatus is so effective is that the high energy UV light helps create chemical species that have not been created before for food sanitization. Also, the interaction between the new chemical species, the ozone, and the cleansing UV light is synergistic, making a three part cleaning system that is highly effective for food sanitization. In addition, while the UV-C light creates ozone, the lower energy UV light emitted by the UV light source aids in the breakdown of the ozone molecules. Thus, the second chemical species has a higher concentration of hydroperoxides than would normally be formed from the breakdown of ozone without the energy UV light. Therefore, because of the apparatus&#39; sanitizing plasmas, the food requires less exposure to UV light than would otherwise be necessary. Also, the plasma allows sanitization on irregular areas which might otherwise be shaded from UV light or other sanitizing radiation.  
      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 made therefrom within the scope of the invention and that obvious modifications will occur to a person skilled in the art.