Patent Publication Number: US-2004058041-A1

Title: Food processing apparatus, method of preserving a food product and preserved food product

Description:
TECHNICAL FIELD  
       [0001] The present invention relates to a food processing apparatus, method of preserving a food product and preserved food product, and more specifically, to a specially treated and packaged food product having a substantially enhanced shelf life.  
       BACKGROUND OF THE INVENTION  
       [0002] Food processors, and retailers of processed food products have endeavored, through the years, to develop and sell processed food products having extended shelf life for consumption by consumers. These efforts to develop food products having an extended shelf life have included, among others, preparing food products which include various additives and other ingredients which, in one fashion, or another, restrain the growth of microbial populations, or the further natural breakdown or deterioration of the food product occasioned by its processing. Various packaging techniques have also been employed, and which may include the use of various thermal treatments which have been utilized to substantially reduce or eliminate microbial populations, or to further create an environment which enhances the shelf life of the product.  
       [0003] While these various methods and other packaging techniques have operated with a great deal of success, various shortcomings are attendant with each of these particular prior art practices. For example, many consumers object to the addition of various additives to their food products in view of accompanying health risks associated with same. For example, some food products have included large amounts of salt as an additive. It is well known that salt has a deleterious effect on those patients suffering from high blood pressure and other cardiovascular disorders. Yet further, certain additives may cause other medical conditions to manifest themselves. An example of such an ingredient are sulfites which may be a trigger periodic and severe migraine headaches in some individuals. Still further, certain food products that are processed using various thermal processing techniques change in there overall appearance, or further, their flavors and textures are modified such that they become undesirable in certain food applications. Moreover, these same prior art techniques often render the food product less than fresh from a consumer&#39;s standpoint, thereby reducing their overall commercial appeal.  
       [0004] One prior art technique which has recently emerged as showing promise in the preservation of various food products includes the use of high pressure processing (HPP). This technique, which is now utilized in Europe, has the effect of substantially inactivating pathogenic microorganisms with minimal heat treatment. This technique also results in the almost complete retention of nutritional and sensory characteristics of the food product without sacrificing shelf life. This technique has also demonstrated advantages over traditional thermal processing of foods by reducing process times and minimizing heat damage problems. Still further this process has also shown a propensity to retain the freshness, flavor and color of the food being processed while not losing substantially any vitamin C. An example of an apparatus which employs the HPP process can be commercially secured under the trade name QFP35L-600 and which is manufactured by Flow International Corporation of Kent, Wash.  
       [0005] Accordingly, a food processing apparatus, method of preserving a food product and preserved food product which achieves the benefits to be derived from the aforementioned technology, but which avoids the determents individually associated with such prior art methods and other techniques, is the subject matter of the present invention.  
       SUMMARY OF THE INVENTION  
       [0006] A first aspect of the present invention relates to a method of preserving a food product and which includes subjecting a food product to be preserved to ultra high hydrostatic pressure in the presence of a liquid treatment.  
       [0007] Another aspect of the present invention relates to a method of preserving a food product and which includes, providing a food product to be preserved; chilling the food product to a temperature; slicing the food product into a plurality of pieces; providing a liquid treatment which is useful in extending the shelf life of the food product; combining the liquid treatment with the plurality of food product pieces; separating the plurality of food product pieces from the liquid treatment; enclosing the plurality of food product pieces into a package; subjecting the package containing the plurality of food product pieces to a hydrostatic pressure of greater than about 80,000 psi for a time period; and refrigerating the resulting packaged food product pieces.  
       [0008] Still another aspect of the present invention relates to a food processing apparatus which includes, a conveyor assembly for moving a food product along a path of travel; a spraying assembly for dispensing a liquid and which is oriented in spraying relation relative to the conveyor assembly; a packaging station positioned downstream of the conveyor; and a hydrostatic pressure application assembly positioned downstream of the packaging station.  
       [0009] Yet another aspect of the present invention relates to a food processing apparatus including, a refrigeration station for chilling a food product to be processed to a temperature; a food treatment station positioned downstream of the refrigeration station, and which receives and cuts the chilled food product into a plurality of pieces; a conveyor assembly positioned downstream of the food treatment station and which transports the plurality of chilled food product pieces along a path of travel; a spraying assembly located along the path of travel, and which dispenses a source of fluid onto the chilled food product pieces which are being transported along the path of travel; a packaging station positioned downstream of the spraying station, and in receiving relation relative to the conveyor, and wherein the sprayed, chilled pieces of food product are enclosed within a package; and a hydrostatic pressure application assembly located downstream of the packaging station and which receives the package of food product pieces and which applies a hydrostatic pressure to the package for a time period.  
       [0010] Another aspect of the present invention relates to a preserved food product which includes a food product which has been subjected to ultra high hydrostatic pressure while simultaneously exposed to a liquid treatment.  
       [0011] A further aspect of the present invention relates to a packaged onion product which includes a peeled and sliced onion which has been previously exposed to a liquid treatment which includes water; calcium chloride; ascorbic acid; and calcium carbonate, and further is subjected to a hydrostatic pressure of at least about 80,000 psi.  
       [0012] Still another aspect of the present invention relates to a packaged onion product including a peeled and sliced onion which has been previously exposed to a liquid treatment which enhances the shelf life of the peeled and sliced onion, and has further been subjected to a hydrostatic pressure, and wherein the packaged onion product has a shelf life in excess of 30 days.  
       [0013] Yet another aspect of the present invention relates to a packaged onion food product which has been exposed to a hydrostatic pressure in an amount which substantially reduces the population of microorganisms which reside on, or in the packaged food product, and further is in an amount which substantially induces enzyme deactivation in the packaged onion.  
       [0014] These and other aspects of the present invention will become more apparent hereinafter. 
     
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
     [0015] Preferred embodiments of the invention are described below with reference to the following accompanying drawings.  
     [0016]FIG. 1 is a greatly simplified graphic depiction of the method and apparatus of the present invention. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
     [0017] This disclosure of the invention is submitted in furtherance of the constitutional purposes of the U.S. Patent Laws“to promote the progress of science and useful arts” (Article 1, Section 8).  
     [0018] A food processing apparatus, method of preserving a food product and preserved food product of the subject invention is best understood by the greatly simplified diagram as shown in FIG. 1 and is generally indicated by the numeral  10 .  
     [0019] As seen in FIG. 1, a source of a food product to be preserved is generally indicated by the numeral  20  and is depicted as an unprocessed, recently harvested onion. While the illustration is that of an onion, the present apparatus and method can be employed to process a variety of different food products including vegetables, meat, poultry, etc. As depicted, the source of the food product  20  is delivered by assorted means to a first refrigeration station  30 . In this first refrigeration station, (assuming the food product to be processed are onions) the food product is refrigerated or otherwise chilled to a temperature of about 36° to about 40° F. Following the step of chilling the food product  20  to a reduced temperature, the food products are taken or otherwise transported to a first food processing station  40 . At this first food processing station, the onion is topped, and tailed, and further the exterior peel is otherwise removed to expose the flesh beneath. The machines for accomplishing this task are well known in the art and further elaboration regarding their construction and operation is not necessary for an understanding of the present invention.  
     [0020] Following the step of delivering the chilled food product  20 , such as an onion, to the first food processing station  40  where it has been topped, tailed and otherwise peeled, the food product  20  may be optionally delivered to a first washing station, which is generally indicated by the numeral  50 . At this first washing station  50 , the peeled food product, such as an onion is exposed to a water solution having a chlorine concentration of at least about fifty (50) ppm., for a time period of about one minute. Following this optional step, the food product is delivered to a second food processing station  60 .  
     [0021] Once the food product  20  has been delivered either directly from the first food processing station  40 , or alternatively from the first optional washing station  50 , the second food processing station  60  is operable to slice, cut or otherwise dice the food product, such as an onion, into a plurality of pieces. Such slicing machines can be purchased from The Hobart Company as the model FP400. A further discussion regarding the slicing machines which may be utilized at the second food processing station  60  is not necessary to a further understanding of the present invention.  
     [0022] Once the food product  20  which is being processed at the second food processing station  60  is sliced or otherwise diced in an appropriate fashion, the sliced food product may be delivered (optionally), to a second washing station which is generally indicated by the numeral  70 . At the second optional washing station  70  the food product  20  such as an onion, is exposed to a second chlorinated water solution for a period of about one minute. The chlorine content of the second chlorinated water solution is at least about fifty (50) ppm. Following the processing of the sliced food product  20  at the processing station  60 , or optionally from the second washing station  70 , the sliced food product  20  is delivered to a conveyor assembly generally indicated by the numeral  80 . The conveyor is of conventional design and may be purchased from assorted manufacturers such as Key Technology, Inc. of Walla Walla, Wash. The conveyor is operable to transport sliced food products (now indicated by the numeral  81 ) along a path of travel which is generally indicated by the numeral  82 .  
     [0023] As further illustrated in FIG. 1, it will be seen that a spraying assembly  90  is provided, and is disposed in liquid dispensing relation relative to the conveyor assembly  80 . The spraying assembly  90  is coupled in fluid flow relation relative to a reservoir  100  by means of a suitable fluid conduit which is generally indicated by the numeral  101 . The reservoir  100  is operable to dispense a liquid treatment  102  directly onto the plurality of food product pieces  81  which are passing along the path of travel  82 . As should be understood, the liquid treatment  102  which is dispensed by the spraying assembly  90 , is a liquid treatment which extends the shelf life of the food product while substantially maintaining the perceived freshness, color, and flavor of the food product. In the case of a food product such as onions, the liquid treatment can be commercially secured under the trademark“NatureSeal ONC-3 Onions” and which is commercially distributed by Mantrose-Bradshaw-Zinsser Group of Westport, Conn. As a general matter, the liquid treatment which is applied to onions includes water, calcium chloride, ascorbic acid, and calcium carbonate. Precise concentrations of these individual ingredients are maintained as proprietary by the manufacturer of this product. The manufacturer of this shelf life extension product,“NatureSeal ONC-3” for onions reports that at best, the product can extend the shelf life of fresh cut onions only for a time period of two to three weeks. The manufacturer also reports that overall, effectiveness of this product is dependent primarily on the quality, variety, and growing conditions of the product. While the present invention is discussed in terms of the above described shelf life extension product, one skilled in the art will recognize that a variety of different liquid treatments may be applied depending upon the food product being processed.  
     [0024] As seen in FIG. 1, and following the step of providing a liquid treatment  102  which is useful in extending the shelf life of the food product  20  to be preserved, and further after combining the liquid treatment and the food product as the food product moves along the path of travel  82 , the food product  81  is removed from the liquid treatment  102  and thereafter delivered to a packaging station which is generally indicated by the numeral  110 . At the packaging station, the sliced food product  81  is enclosed within an appropriate package and is thereafter covered with an oxygen permeable film and sealed within the package. Appropriate packaging may be secured from CPT/Green Tek Plastics.  
     [0025] As seen in FIG. 1, following the step of placing the sliced food product into appropriate packaging at the packing station  110 , the packaged food product is then delivered to a hydrostatic pressure application assembly which is generally indicated by the numeral  120 , and where the packaged food product is subjected to ultra high pressure in the presence of the liquid treatment previously applied by the spraying assembly  90 . The ultra high pressure is applied by a hydrostatic pressure application assembly which may be commercially secured from Flow International, Inc. located in Kent, Washington. As a general matter, the amount of hydrostatic pressure which is applied is in an amount which is useful in substantially inducing enzyme deactivation in the packaged food product and/or further reducing the population of various microorganisms which may reside on or in the packaged food product. Hydrostatic pressure is applied for a time period of at least about one minute. The amount of the hydrostatic pressure is at least about 50,000 psi. In the development of a preserved food product such as packaged onions, the hydrostatic pressure which has been found useful is greater than about 80,000 psi. Once the processed food product, such as packaged sliced onions have been exposed to the hydrostatic pressure for a time period, the packaged food product is then removed from the ultra high pressure and placed in a second refrigeration station  130  where they are maintained at a reduced temperature prior to being delivered to retailers for sale.  
     [0026] Therefore, as will be seen from FIG. 1 the method of preserving a food product in its broadest aspect includes subjecting a food product  20  to be preserved to ultra high pressure in the presence of a liquid treatment  102 . More specifically the method of preserving a food product includes providing a food product to be preserved  20 ; providing a liquid treatment  102  which is useful in extending the shelf life of the food product to be preserved; combining the liquid treatment  102  and the food product  20 ; removing the food product from the liquid treatment; and subjecting the food product to a hydrostatic pressure of greater than about 80,000 psi for a time period in the presence of the liquid treatment. As applied to such food products as onions, FIG. 1 illustrates the contemplated steps in the present method for preserving a food product which includes providing a food product to be preserved  20 ; chilling the food product to a temperature  30 ; slicing the food product into a plurality of pieces  60 ; providing a liquid treatment which is useful in extending the shelf life of the food product  102 ; combining the liquid treatment with the plurality of food pieces  81 ; separating the plurality of food pieces from the liquid treatment  102 ; enclosing the plurality of food pieces  81  into a package  110 ; subjecting the package containing the plurality of food product pieces to a hydrostatic pressure of greater than about 80,000 psi for a time period  120 ; and refrigerating the resulting packaged food product pieces  130 .  
     [0027] A food processing apparatus for implementing the method as described above is also illustrated in FIG. 1, and includes as a general matter, a conveyor assembly  80  for moving a food product  81  along a path of travel  82 . Still further the food processing apparatus includes a spraying assembly  90  for dispensing a liquid  102 , and which is oriented in spraying relation relative to the conveyor assembly  80 . Still further, a packaging station  110  is positioned downstream of the conveyor  80 ; and further a hydrostatic pressure application assembly  120  is provided and positioned downstream of the packaging station.  
     [0028] As illustrated in FIG. 1, the food processing apparatus as described in the paragraph immediately above includes food processing stations  40 , and  60  positioned upstream of the conveyor assembly  80 . Still further, a refrigeration station  30  is positioned upstream of the conveyor assembly  80 , and which is operable to chill a food product  20  to be processed to a temperature. As also seen in FIG. 1, the food processing stations  40 , and  60  are positioned upstream of the conveyor assembly  80  and downstream of the refrigeration station  30 . As earlier disclosed, the food processing stations  40 , and  60  are operable to process the food product  20  in such a manner so as to produce a plurality of product pieces  81 . As seen in the drawing, a reservoir  100  is provided and coupled in fluid flowing relation with a spraying assembly  90  and which is operable to deliver a liquid treatment  102  which extends the shelf life of the food product  81 . As seen in FIG. 1, the conveyor  80  transports the sliced food product  81  along a path of travel  82  where it is exposed to the treatment  102  which is dispensed from the spraying assembly  90 . The hydrostatic pressure application assembly  120  is operable to provide a pressure to achieve the benefits earlier disclosed.  
     [0029] A food processing apparatus of the present invention therefore includes, as a general matter, a refrigeration station  30  for chilling a food product  20  to be processed to a temperature; food treatment stations  40 , and  60  positioned downstream of the refrigeration station, and which receives and cuts the chilled food product into a plurality of pieces; a conveyor assembly  80  positioned downstream of the food treatment stations, and which transports the plurality of chilled food product pieces  81  along a path of travel  82 ; a spraying assembly  90  located along the path of travel  82 , and which dispenses a source of liquid treatment  102  onto the chilled food product pieces  81  which are being transported along the path of travel; a packaging station  110  positioned downstream of the spraying station and in receiving relation relative to the conveyor, and wherein the sprayed, chilled pieces of food product are enclosed within a package; and a hydrostatic pressure application assembly  120  located downstream of the packaging station and which receives the packaged food product pieces and which applies a hydrostatic pressure to the package for a time period.  
     [0030] The method and apparatus of the present invention  10  provides a preserved food product which comprises a food product which has been subjected to ultra high hydrostatic pressure while simultaneously exposed to a liquid treatment. As noted above, where the food product being processed are onions, the ultra high hydrostatic pressure is at least about 50,000 psi. Still further, the liquid treatment which is applied extends the shelf life of the food product while substantially maintaining the perceived freshness, color and flavor of the food product. In the case of onions, the liquid treatment as earlier discussed comprises water; calcium chloride; ascorbic acid; and calcium carbonate. This shelf life extender can be commercially secured as disclosed earlier. As seen in FIG. 1, the packaged, peeled, and cut food products, such as onions, are refrigerated in the second refrigeration station  130  following exposure to the ultra high hydrostatic pressure applied by the hydrostatic pressure application assembly  120 .  
     [0031] The present apparatus and method provides a convenient means for providing a packaged onion product which comprises a peeled and sliced onion which has been previously exposed to a liquid treatment which includes water; calcium chloride; ascorbic acid; and calcium carbonate, and further is subjected to a hydrostatic pressure of at least about 80,000 psi. The present method and apparatus also provides a packaged onion product which has a self life in excess of 30 days. This shelf life is more than 10 days longer than conventional prior art practices can provide. As discussed above, the hydrostatic pressure applied at station  120  is in an amount which substantially induces enzyme deactivation in the packaged onion product. Still further, the hydrostatic pressure is in an amount which substantially reduces populations of microorganisms which reside on or in the packaged onion product.  
     [0032] Therefore, as seen in FIG. 1, the invention  10  allows for the implementation of a method of preserving a food product  20  and wherein the food processing apparatus includes a means for moving a food product along a path of travel  80 ; a means for dispensing a liquid onto the food product  90  as it moves along the path of travel  80 ; means for enclosing the food product into a package  110  following the dispensing of the liquid  102  onto the food product  81 ; and means for applying hydrostatic pressure  120  to the packaged food product.  
     [0033] Therefore it will be seen that the invention provides a convenient apparatus, method and other means by which a food product, such as onions, may be conveniently processed, packaged and preserved and which have extended shelf life which is significantly greater than processed onions using conventional prior art processes and techniques.  
     [0034] In compliance with the statute, the invention has been described in language more or less specific as to structural and methodical features. It is to be understood, however, that the invention is not limited to the specific features shown and described, since the means herein disclosed comprise preferred forms of putting the invention into effect. The invention is, therefore, claimed in any of its forms or modifications within the proper scope of the appended claims appropriately interpreted in accordance with the doctrine of equivalents.