High humidity steam cooker with continuously running conveyor

Abstract

A steam cooker processes large quantities of food products such as meat, fish, poultry and produce passed therethrough in a spiral conveyor path. The continuously running conveyor is provided with loading and unloading stations outside the cooker and with a continuously operable spray detergent cleaning bath. Efficient cooking is achieved without loss of humidity, flavor or appearance by maintaining water drop free steam at near 100° C. and 100% humidity at a pressure greater than atmospheric and by features of the apparatus including control of steam flow out of the cooking chamber and introduction of cold air thereinto. Two separate steam sources, internal and external, are provided with the internal source comprising a heated pool of water on the floor of the cooker chamber, which is agitated for heat transfer efficiency and to remove fat or drippings from the cooking products. Sanitation means include mounting of machinery parts outside the cooker, access to all sides of the cooking chamber for cleaning, an internal cleaning spray system and other apparatus features.

I claim: .[. 
     
       1.  A food cooking system cooking solely with steam foods such as fish, fowl, meats or produce carried through a cooker on a continuously running conveyor belt, comprising in combination, a cooker housing, means passing said conveyor belt through said housing to expose food products within the cooker housing only to said steam as the sole cooking medium, and two sources of steam providing said steam to cook the food products, nozzles for releasing steam located inside said housing, one comprising a steam generator supplying supplemental steam into said housing at said nozzles located thereinside to maintain the atmosphere together with the other steam source at near 100% humidity 100° C. and a pressure above atmospheric, and the other source of steam comprising a pool of water within said housing with heating means for boiling the water to create steam..]. .[.2. The system defined in claim 1 having a steam exhaust pipe, and heat control means for said pool of water regulated as a function of the temperature at said exhaust pipe..]. .[.3. The system defined in claim 1 having an opening in said housing into which said conveyor belt passes, and means establishing said steam pressure at a sufficient magnitude to discharge steam at a controlled rate from said housing about the entering conveyor belt..]. .[.4. The system defined in claim 3 with an opening in said housing out of which the conveyor belt passes, and having a steam flow path created within said housing by said nozzles tending to draw air into the latter said opening to produce a flow path out of the former opening thereby circulating air and steam..]. .[.5. A system as defined in claim 1 including means driving said conveyor belt through said housing with all mechanisms requiring lubrication mounted in a compartment outside the housing thereby to avoid food contamination..]. .[.6. A system as defined in claim 1 wherein the housing is positioned within a secondary housing such as a room where the pressure is maintained above atmospheric..]. .[.7. A system as defined in claim 6 including a station for loading food products through which said conveyor belt passes outside said secondary housing so that the food products are maintained at atmospheric pressure until they enter the cooker system whereby the increased pressure and high humidity cause efficient penetration of heat into the products to cook them evenly throughout by establishing a temperature approaching 100° C..]. .[.8. A system as defined in claim 1 adapted for processing meat and fowl products which may drip fat into said pool of water, including means continuously skimming the fat 
     
     
        from the top of the water to improve the steam capacity thereof..]. .[.9. A system as defined in claim 8 wherein the fat skimming means comprises a paddle wheel on one side of the pool generating waves travelling to the other side of the pool and a fat skimmer receiving the crest of the waves and fat residing therein and removing such from the pool of water..]. .[.10. A system as defined in claim 8 wherein the heating means for the pool of water comprise heat exchange elements at the bottom of said housing, including means circulating the water over said heat exchange elements to improve the effective steam output efficiency..]. .[.11. A system as defined in claim 1 wherein said housing has access doors for entry thereinto on all sides..]. .[.12. A system as defined in claim 1 wherein the conveyor belt is passed inside said housing in a spiral path coiling downwardly to carry said foods through said housing from an upper to a lower position in said near 100% humidity atmosphere which prevents water dripping downwardly upon the foods being cooked on the belt..]. .[.13. A system as defined in claim 1 including means pre-moistening the food products on said conveyor belt before entry into said housing to thereby create an efficient heat interchange surface on the food products for heating by said steam..]. .[.14. The system defined in claim 13 wherein the conveyor belt path passes from a loading station at atmospheric pressure into an enclosure above atmospheric pressure and said moistening means comprises means located within said enclosure producing a fine spray mist covering the surface of the food product on the belt without droplets or steaming..]. .[.15. A self-contained continuous meat cooking system comprising: a cooker housing which establishes an interior space;   meat-conveyance means for introducing meat into said interior space at an inlet of said cooker housing and for removing the meat from said interior space at an outlet of said cooker housing vertically spaced from said housing inlet;   said meat-conveyance means defining a spiral path of conveyance for said meat in said interior space, which spiral path includes a predetermined number of convolutions so as to establish a sufficient dwell time for the meat in said interior space as the meat is continually translated along said defined path between said housing inlet and said housing outlet;   said cooker housing including (i) an internal pool of water having a surface level below a lowermost one of said convolutions of said meat-conveyance means, and (ii) means in heat-exchange relationship to said pool of water for converting a quantity of water in said pool to steam which is contained within said interior space of said housing to thereby provide a steam atmosphere within said interior space to at least in part cook the meat during the continual translation of the meat along said spiral path, whereby cooked meat exits the cooker housing at said outlet thereof..]. .[.16. A meat cooking system as in claim 15, which further comprises skimmer means for continually removing a residual floating film of meat-cooking by-products from said surface level of said pool of water..]. .[.17. A meat cooking system as in claim 16, wherein said skimmer means includes a skimmer adapted to collect the removed meat-cooking by-products, and means for creating travelling disturbances on said surface level of said pool of water which cause said floating film to move towards said skimmer to be collected thereby..]. .[.18. A meat cooking system as in claim 15, wherein,   said meat-conveyance means includes an endless conveyor for supporting said meat during its continual translation along said spiral path and which includes a return path exterior of said cooker housing between said outlet and inlet, and wherein the system further comprises   means located along said return path exterior of said cooker housing for cleaning said endless conveyor before it reenters said cooker housing   
     
     
        inlet..]. .Iadd.19.  A system for at least partially cooking substantially uncovered food products such as poultry parts, said cooking being performed at least in part with steam, said system comprising: a housing defining an internal volume having a spiral conveyance path therein,   a conveyor belt disposed along said spiral conveyance path, said conveyor belt adapted for supporting and carrying said uncovered food products through said internal volume,   a belt drive mechanism coupled to said conveyor belt, said belt drive mechanism driving said conveyor belt to continually translate said belt along said spiral conveyance path through said housing to expose said supported and carried uncovered food products to a high humidity steam atmosphere,   a steam source operatively coupled to said housing, said steam source providing said high humidity steam atmosphere within said internal volume, said steam atmosphere directly contacting and at least partially cooking the uncovered food products, and   an internal cleaning spray arrangement at least in part disposed within said housing, said internal cleaning spray arrangement, in use, spraying the inside of said housing with a sanitizing solution. .Iaddend.   
     
     
        .Iadd.     A cooking system for cooking food products such as poultry, said cooking system comprising: a housing including thermally insulated walls, said housing defining a spiral conveyance path therein;   a conveyor belt defining an open grating, said belt being disposed along said path, said conveyor belt adapted for supporting exposed food products;   a drive mechanism mechanically coupled to said belt, said drive mechanism moving said belt and said exposed food products supported thereon along said spiral path, said path having sufficient convolutions to retain said translating food products within said housing for a desired dwell time so as to heat said poultry products within said housing to a desired temperature;   a steam source coupled to said housing, said steam source providing a high humidity steam atmosphere within said housing, said high humidity steam atmosphere directly contacting outer surfaces of said exposed food products so as to at least in part heat and cook said food products; and   an internal cleaning spray arrangement at least in part disposed within said housing, said internal cleaning spray arrangement, in use, spraying the inside of said housing with a sanitizing solution. .Iaddend. .Iadd.21. A cooking apparatus adapted for cooking food products such as poultry parts having an outer fat layer, said apparatus comprising:   a housing defining a spiral conveyance path therein;   an endless belt at least partially disposed along said spiral path, said belt adapted for supporting and continually translating exposed food products along said spiral conveyance path; and   a steam source providing high humidity steam within said housing in direct contact with the outer surfaces of said exposed food products supported and translated by said belt so as to at least in part cook said food products while said food products are within said housing;   an arrangement coupled to said housing which continually removes fat byproducts from said housing while said food products are cooking within said housing; and   an internal cleaning spray arrangement at least in part disposed within said housing, said internal cleaning spray arrangement, in use, spraying the inside of said housing with a sanitizing solution. .Iaddend.   
     
     
        .Iadd.     A meat cooking apparatus as in claim 21 further including an automatic cleaning arrangement disposed outside said housing and in proximity to a portion of said belt, said cleaning arrangement continually cleaning said belt. .Iaddend. .Iadd.23. A cooking apparatus adapted for cooking food products such as poultry parts having an outer fat layer, said apparatus comprising: a housing defining a spiral conveyance path therein;   an endless belt at least partially disposed along said spiral path, said belt adapted for supporting and continually translating exposed food products along said spiral conveyance path;   a steam source providing high humidity steam within said housing in direct contact with the outer surfaces of said exposed food products supported and translated by said belt so as to at least in part cook said food products while said food products are within said housing; and   an arrangement coupled to said housing which continually removes fat byproducts from said housing while said food products are cooking within said housing,   said cooking apparatus further including a premoistening arrangement disposed in proximity to a loading portion of said belt, said premoistening arrangement premoistening surfaces of said exposed food products supported by said belt before said food products enter said housing so as to reduce insulation characteristics of said fat layer to thereby facilitate more rapid cooking of said food products by said steam.   
     
     
        .Iaddend. .Iadd.24.  A spiral steam cooker for at least partially cooking exposed food products in a high humidity steam atmosphere, said cooker comprising: a housing defining an internal volume therein;   an endless conveyor belt at least partially disposed along a spiral conveyance path within said internal volume, said conveyor belt adapted for supporting and carrying said food products in an exposed manner through said internal volume;   a belt drive mechanism coupled to said conveyor belt, said belt drive mechanism driving said conveyor belt to continually translate along said spiral conveyance path,   a steam source providing said high humidity steam atmosphere within said internal volume, said high humidity steam atmosphere directly contacting and at least partially cooking the exposed food products, and   an internal cleaning spray arrangement at least in part disposed within said housing, said internal cleaning spray arrangement, in use, spraying the inside of said housing with a sanitizing solution. .Iaddend.   
     
     
        .Iadd.     A spiral steam cooker for heating and at least partially cooking exposed food products, said cooker comprising: a housing defining an internal volume therein;   an endless conveyor belt at least partially disposed along a spiral conveyance path within said internal volume, said conveyor belt for, in use, supporting and carrying said exposed food products through said internal volume, said conveyor belt being adapted to continually translate along said spiral conveyance path through said housing,   a steam source disposed within said housing, said steam source providing a steam atmosphere within said internal volume, said steam atmosphere directly contacting and at least partially cooking the exposed food products, and   at least one additional source of heat introducing heat into said housing. .Iaddend. .Iadd.26. A cooker as in claim 25 further including means for   
     
     
        continually removing liquified fat from said housing. .Iaddend. .Iadd.27. A cooker as in claim 25 wherein said steam source includes a heated pool of water disposed at the bottom of said housing. .Iaddend. .Iadd.28. A spiral steam cooker for at least partially cooking exposed food products, said cooker comprising: a housing defining an internal volume therein;   a conveyor belt at least partially disposed along a spiral conveyance path within said internal volume, said conveyor belt for, in use, supporting and carrying said exposed food products through said internal volume, said conveyor belt adapted to continually translate along said spiral conveyance path through said housing; and   a steam source operatively coupled to said housing, said steam source providing a high humidity steam atmosphere within said internal volume, said high humidity steam atmosphere directly contacting and at least partially cooking the exposed food products, said steam source including at least one steam pipe for injecting steam into said housing and for substantially filling said housing with said high humidity steam atmosphere. .Iaddend. .Iadd.29. A food cooking system for cooking food products with steam as said food products are supported on a moving conveyor belt, said food cooking system comprising:   a cooker housing,   means disposed within said housing for defining a conveyance path,   a conveyor belt disposed along said conveyance path for supporting and carrying said food products along said path,   means coupled to said belt for causing said belt and said food products supported thereby to substantially continually translate along said conveyance path through said housing to expose food products within the housing to steam, said path retaining said translating food products within said housing for at least a desired dwell time, and   a source of steam providing steam to contact and cook the food products, said steam source comprising at least one of the following: an external steam generator supplying steam into said housing, and   a pool of water within said housing with heating means communicating with said pool of water for creating steam,     wherein said steam source provides high humidity steam and said food products are directly exposed to said high humidity steam. .Iaddend.   
     
     
        .Iadd.0.  A food cooking system for cooking food products with steam as said food products rest on a moving conveyor belt, said food cooking system comprising: a cooker housing,   means disposed within said housing for defining a conveyance path,   a conveyor belt disposed along said conveyance path for supporting and conveying said food products along said path,   means coupled to said belt for causing said belt and said food products supported thereby to substantially continually translate along said conveyance path through said housing to expose food products within the housing to steam, said path retaining said translating food products within said housing for at least a desired dwell time, and   a source of steam providing steam to contact and cook the food products, said steam source comprising at least one of the following: an external steam generator supplying into said housing, and   a pool of water within said housing with heating means communicating with said pool of water for creating steam,     wherein steam within said housing condenses into a condensate and said steam source recirculates at least some of said condensate as steam.   
     
     
        .Iaddend. .Iadd.31.  A continuous food cooking system for cooking food products with steam, said food cooking system comprising: a housing;   means for defining an internal conveyance path within said housing;   means disposed along said internal conveyance path for supporting and substantially continually translating food products along said internal path, said food products cooking while within said housing and producing a by-product, said path having sufficient convolutions to retain said translating food products within said housing for a desired dwell time; and   a steam source providing steam to contact and cook the food products, said steam source comprising at least one of the following:   an internal steam generator supplying steam into said housing, and   a pool of water within said housing with heating means communicating with said pool of water for creating steam,   wherein said steam source provides high humidity steam and said food products are directly exposed to said high humidity steam. .Iaddend.   
     
     
        .Iadd.2.  A continuous food cooking system for heating and at least partially cooking food products with steam, said continuous food cooking system comprising: a housing;   a belt disposed along an internal spiral conveyance path within said housing, said belt, in use, supporting said food products such that said food products rest directly upon an upper surface of said belt, said belt substantially continually translating along said conveyance path within said housing so as to heat and at least partially cook said food products while said food products are within said housing;   a steam providing arrangement disposed, at least in part, within said housing for providing steam within said housing, said steam providing arrangement providing a high humidity steam atmosphere within said housing, said high humidity steam atmosphere which contacts, heats, and at least partially cooks said food products as said food products translate along said path;   a by-product removing arrangement for continually removing, from said housing, by-products such as fat released by said cooking food products; and   an internal cleaning spray arrangement at least in part disposed within said housing, said internal cleaning spray arrangement, in use, spraying the inside of said housing with a sanitizing solution. .Iaddend. .Iadd.33. A system as in claim 32 wherein said by-product removing arrangement is located at least partially within said housing. .Iaddend. .Iadd.34. A system as in claim 32 wherein said steam providing arrangement provides said high humidity steam atmosphere at near 100% humidity. .Iaddend.   
     
     
        .Iadd.5.  A system as in claim 32 wherein said by-product removing arrangement prevents fat released by said cooking food products from being broken down into a residue gas which would adversely flavor the food products. .Iaddend. .Iadd.36. A system as in claim 32 wherein said by-product removing arrangement cooperates with said housing to substantially prevent fat released by said cooking food products from forming a scum within said housing that is not easily removable from said housing. .Iaddend. .Iadd.37. A system as in claim 32 wherein said housing has first and second walls, and said system includes at least one access door in each of said first and second walls. .Iaddend. .Iadd.38. A system as in claim 32 wherein said system further includes a spray wash unit, wherein said belt passes through said spray wash unit so as to clean said belt. .Iaddend. .Iadd.39. A system as in claim 38 wherein said belt cleaning is performed on a substantially continuous basis. .Iaddend. .Iadd.40. A system as in claim 38 wherein said spray wash unit includes at least one spray nozzle which generates a liquid spray, and said belt has an open grating upon which the products rest, said open grating permitting said liquid spray to flow through said belt. .Iaddend. .Iadd.41. A system as in claim 38 wherein said spray wash unit includes a continually running motor-pump which continually recirculates at least a portion of said liquid spray through said spray wash unit. .Iaddend. .Iadd.42. A system as in claim 41 wherein said spray wash unit further includes a filter for filtering at least a portion of said liquid spray prior to recirculating. .Iaddend. .Iadd.43. A system as in claim 38 wherein said spray wash unit includes a sump for holding said liquid spray and permitting recirculation thereof. .Iaddend. .Iadd.44. A system as in claim 38 wherein said spray wash unit is adapted to spray a detergent spray solution. .Iaddend. .Iadd.45. A system as in claim 38 wherein said spray wash unit includes sufficient spray nozzles and provides sufficient spray pressure to as to dislodge crumbs and/or drippings remaining on the belt after said food 
     
     
        products are unloaded from the belt. .Iaddend. .Iadd.46.  A system as in claim 32 further including an outlet stack which lets steam flow out of said housing in a controlled amount. .Iaddend. .Iadd.47. A system as in claim 32 wherein convolutions of said belt disposed within said housing are not lubricated. .Iaddend. .Iadd.48. A system as in claim 32 further including a fan coupled to said housing for creating a flow of high humidity steam within said housing. .Iaddend. .Iadd.49. A system as in claim 32 further including a fan coupled to said housing for creating a gas flow which is counter to the direction of travel of said belt. .Iaddend. .Iadd.50. A system as in claim 32 wherein said belt is wide enough to support several side-by-side pieces of meat, produce, fish or poultry. .Iaddend. .Iadd.51. A system as in claim 42 wherein said system has a throughput capacity of in excess of a ton of food product per hour. .Iaddend. .Iadd.52. A system as in claim 32 wherein said system is capable 
     
     
        of providing a dwell time of at least twenty minutes. .Iaddend. .Iadd.53. A system as in claim 32 wherein said system is capable of heating said food products to a temperature of at least 97 degrees centigrade. .Iaddend. .Iadd.54. A system as in claim 32 wherein said internal cleaning spray arrangement includes a spray pipe not used by said steam providing arrangement. .Iaddend. .Iadd.55. A system as in claim 32 wherein said steam providing arrangement provides a constant circulating flow of high humidity steam about the products being carried on said belt. .Iaddend. 
     
     
        .Iadd.56.  A system as in claim 32 wherein said steam providing arrangement includes means for flowing steam in a direction counter to the direction of translation of said belt to create a circulation path. .Iaddend. .Iadd.57. A system as in claim 32 wherein said steam providing arrangement creates a circulation of steam within said housing. .Iaddend. .Iadd.58. A system as in claim 32 further including a circulation fan for introducing a desired ratio of outside air into the housing for 
     
     
        circulation. .Iaddend. .Iadd.59.  A system as in claim 32 wherein a portion of said belt is disposed along a path outside of said housing, and a belt cleaning system continually cleans said portion of said belt outside of said housing. .Iaddend. .Iadd.60. A system as in claim 32 further including an arrangement for recovering said removed by-products so as to permit said by-products to be useable. .Iaddend. .Iadd.61. A system as in claim 32 wherein said housing has at least one opening through which said belt travels, and said system further includes means for resisting the flow of hot air or steam out of said housing. .Iaddend. .Iadd.62. A system as in claim 32 wherein said by-product removing arrangement prevents any accumulation of fat film on a surface near the bottom of said housing. .Iaddend. .Iadd.63. A system as in claim 32 wherein said by-product removing arrangement includes a means outside of said housing for segregating fats from said by-product. .Iaddend. .Iadd.64. A system as in claim 32 further including a belt drive mechanism disposed outside of said housing, said belt drive mechanism causing said belt to translate. .Iaddend. .Iadd.65. A system as in claim 32 wherein said belt path has as many convolutions as necessary to retain particular specialty products within the housing for a desired dwell time and belt travel speed. .Iaddend. .Iadd.66. A system as in claim 32 wherein said housing walls are insulated to preserve heat and to produce a safe and lower temperature outside wall environment. .Iaddend. .Iadd.67. A system as in claim 32 wherein said steam providing arrangement includes a steam generator unit external to said housing. .Iaddend. .Iadd.68. A system as in claim 67 wherein said steam providing arrangement has components made of stainless steel. .Iaddend. .Iadd.69. A system as in claim 67 wherein said steam providing arrangement is adapted to be coupled to a boiler. .Iaddend..Iadd.70. A system as in claim 67 wherein said steam providing arrangement is adapted to be supplied with sanitary steam, and includes a stainless steel sanitary steam pipe with pipe insulation having sanitary jacketing. .Iaddend. .Iadd.71. A system as in claim 32 wherein said 
     
     
        housing has a floor with a drain therein. .Iaddend. .Iadd.72.  A continuous food cooking system for heating and at least partially cooking food products with steam, said continuous food cooking system comprising: a housing;   a belt disposed along an internal spiral conveyance path within said housing, said belt, in use, supporting said food products such that said food products rest directly upon an upper surface of said belt, said belt substantially continually translating along said conveyance path within said housing so as to heat and at least partially cook said food products while said food products are within said housing;   a steam providing arrangement disposed, at least in part, within said housing for providing steam within said housing, said steam providing arrangement providing a high humidity steam atmosphere within said housing, said high humidity steam atmosphere which contacts, heats and at least partially cooks said food products as said food products translate along said path; and   a by-product removing arrangement for continually removing, from said housing, by-products such as fat released by said cooking food products,   said system further including:   a gas discharge stack for discharging steam from said housing; and   a temperature sensor coupled to said gas discharge stack, said temperature sensor sensing the temperature of the steam discharged by said gas   
     
     
        discharge stack. .Iaddend. .Iadd.73.  A system as in claim 72 wherein said steam providing arrangement is responsive to said sensed temperature. .Iaddend. .Iadd.74. A system as in claim 72 wherein said steam providing arrangement provides an amount of steam responsive to the temperature sensed by said temperature sensor. .Iaddend. .Iadd.75. A continuous food cooking system for heating and at least partially cooking food products with steam, said continuous food cooking system comprising: a housing;   a belt disposed along an internal spiral conveyance path within said housing, said belt, in use, supporting said food products such that said food products rest directly upon an upper surface of said belt, said belt substantially continually translating along said conveyance path within said housing so as to heat and at least partially cook said food products while said food products are within said housing;   a steam providing arrangement disposed, at least in part, within said housing for providing steam within said housing, said steam providing arrangement providing a high humidity steam atmosphere within said housing, said high humidity steam atmosphere which contacts, heats and at least partially cooks said food products as said food products translate along said path; and   a by-product removing arrangement for continually removing, from said housing, by-products such as fat released by said cooking food products,   said system further including a heat source in addition to said steam providing means, said additional heat source introducing additional heat into said housing for heating and at least in part cooking said food   
     
     
        products. .Iaddend. .Iadd.76.  A continuous food cooking system for heating and at least partially cooking food products with steam, said continuous food cooking system comprising: a housing;   a belt disposed along an internal spiral conveyance path within said housing, said belt, in use, supporting said food products such that said food products rest directly upon an upper surface of said belt, said belt having an open grating which permits steam and liquid to flow through said belt, said belt substantially continually translating along said conveyance path within said housing so as to at least partially cook said food products while said food products are within said housing;   a steam providing arrangement disposed within said housing for providing steam within said housing, said steam providing arrangement providing a high humidity steam atmosphere within said housing, said high humidity steam atmosphere contacting and at least partially cooking said food products as said food products translate along said path; and   an internal cleaning spray arrangement at least in part disposed within said housing, said internal cleaning spray arrangement, in use, spraying the inside of said housing with a sanitizing solution. .Iaddend.   
     
     
        .Iadd.     A system as in claim 76 wherein: said housing further includes a floor with a drain; and   said system further includes means for selectively permitting said sanitizing solution to exit said housing through said drain. .Iaddend.