Description:TECHNICAL FIELD
[0001] The present invention is related to systems and methods for thermally processing packaged food products and sealed food packages.
BACKGROUND
[0002] Thermal processing apparatus are known in many variants. Each of them is designed to perform a thermal processing, which for example can be sterilization or pasteurization, in order to obtain increased shelf stability. For thermal processing of sealed flexible food packages, batch retort systems at present are mostly used. With this the flexible packages are laid down on large square or rectangular product trays. These trays then are stacked to cubes and these cubes are then placed inside of a static pressure vessel where they undergo a heat treatment. A well-known disadvantage hereof is the large difference in heat treatment that the food products inside the packages in the centre of the cubes undergo compared to the ones at the outside. This potentially leads to a loss of food product quality. Furthermore, those batch retort systems are inefficient because of the multiple handling involved, and because of the discontinuous use of the vessel.
[0003] Most food products have a tendency to spoil relatively quickly. As such, preservation techniques have been developed over many years to extend the amount of time that a given food product will remain fresh. Food preservation techniques can include dehydrating, freezing, fermenting, pickling, acidification, curing, canning, heat treating, retort sterilization, irradiating, chemical preservation and the like.
[0004] Although food is generally inspected prior to packaging, it is presently not practical to inspect each package of food for complete application of an antimicrobial agent to the product. Incomplete or otherwise insufficient application reduces the efficacy of the antimicrobial.
[0005] Traditional retort sterilization typically involves the application of heat to hermetically sealed packages of food through thermal conduction. Retort sterilization allows for packaged non-frozen and non-dehydrated ready-to-eat foods that can have a shelf life of months to years.
[0006] It is also known to perform a continuous thermal processing of such sealed flexible food packages. This offers major advantages regarding to energy efficiency, water consumption, floor space utilization and operator efficiency. For the continuous thermal processing it is required that the flexible food packages are first placed inside product carriers that are connected to an endless conveyor. The conveyor then, at a substantially continuous speed, transports the flexible food packages through various thermal processing stages, like preheating, sterilizing and cooling. Existing technology for placing the flexible food packages in the product carriers is often done by using intermediate product trays. With this the flexible food package are first laid down on the intermediate product trays. Then in the next step those trays are placed into the product carriers. This existing technology, however, is inefficient because of the dual handling involved, one for filling of the product trays, and one for putting the product trays in the product carrier. Also they are not suitable for higher capacities of, for example, more than 300 flexible packages per minute.
[0007] The present invention aims to overcome the above disadvantages at least partly or to provide a usable alternative. In particular the invention aims to provide a user-friendly and reliable apparatus for thermally processing food packages with which the food packages can be positively handled during insertion into and/or removal out of a product carrier without running the risk of getting damaged and without negatively influencing the thermal processing.
SUMMARY
[0008] Embodiments of the present disclosure present technological improvements as solutions to one or more of the above-mentioned technical problems.
[0009] Before the present subject matter relating to apparatus for thermally processing food packages, it is to be understood that this application is not limited to the particular system described, as there can be multiple possible embodiments which are not expressly illustrated in the present disclosure. It is also to be understood that the terminology used in the description is for the purpose of describing the implementations or versions or embodiments only and is not intended to limit the scope of the present subject matter.
[0010] This summary is provided to introduce aspects related to apparatus for thermally processing food packages. This summary is not intended to identify essential features of the claimed subject matter nor is it intended for use in determining or limiting the scope of the present subject matter.
[0011] It is noted that the present invention seeks to kill the targets in place; rather than try to remove them. In general, dead enterobacteria are not harmful to humans. These bacteria do not form spores, nor do they produce any toxins which act after their death, as do some Clostridia.
[0012] In one embodiment, apparatus for thermally processing food products in sealed packages, in particular flexible food packages comprising: one or more heating and/or cooling chambers; an endless conveyor guided through the chambers; a plurality of product carriers connected interspaced to the conveyor, in which each carrier comprises at least a first row of insertion spaces for packages to be placed in, which insertion spaces each have an insertion opening and which first row of insertion spaces is at least partly delimited by a first side wall and an opposite second side wall; and an inlet station comprising one or more first operating members operable to move into and out of the insertion spaces for moving packages in an insertion direction into the insertion spaces; in which the conveyor is designed for transporting the carriers with packages placed in the insertion spaces thereof through the one or more heating and/or cooling chambers, characterized in that, the first side wall comprises at least one primary slit for each insertion space, which primary slit extends substantially in said insertion direction, and which primary slit opens out towards the insertion opening of said respective insertion space, wherein the first operating members comprise load bearing organs operable for picking up and carrying packages, which load bearing organs extend substantially in a transverse direction relative to said side walls, and which load bearing organs are movable in said insertion direction while projecting through the primary slits during placing of packages into the first row of insertion spaces.
[0013] In another embodiment, systems and methods for thermally processing packaged food products with highly-uniform electromagnetic energy fields. In an embodiment, a method of thermally processing a packaged food product is included herein. The method can include placing the packaged food product in a heating chamber, the packaged food product comprising a hermetically sealed package and a food material disposed within the package. The method can further include applying electromagnetic energy to the packaged food product from a first electromagnetic energy source from a first direction. The electromagnetic energy can be sufficient to raise the temperature of the food material by at least 50 degrees Fahrenheit with a spatial temperature variation of less than 25 degrees Fahrenheit in less than 120 seconds.
[0014] In another embodiment, improved methods for controlling contamination of vacuum-sealed food products by a combined treatment comprising (1) a thermal surface treatment and (2) application of one or more antimicrobial agents to the surface of food products, whereby the thermal surface treatment and the application of the antimicrobial solution are, in combination, effective for killing or inactivating essentially all pathogenic contamination in the vacuum-sealed food product. The present methods can easily be incorporated into a vacuum packaging line such as a web packaging system wherein the food product is packaged and sealed between upper and lower webs.
BRIEF DESCRIPTION OF ACCOMPANYING DRAWINGS
[0015] The detailed description is described with reference to the accompanying figures. In the figures, the left-most digit(s) of a reference number identifies the figure in which the reference number first appears. The same numbers are used throughout the drawings to reference features and modules.
[0016] Figure 1 illustrates a schematic view of a hydrostatic continuous sterilizer apparatus with vertically orientated tower sections according to the invention.
[0017] Figure 2 illustrates a schematic view of phases of thermally processing packaged food products in accordance with various embodiments herein.
[0018] Figure 3 illustrates a general flowchart of improved methods for controlling contamination of vacuum-sealed food products.
[0019] It should be appreciated by those skilled in the art that any block diagrams herein represent conceptual views of illustrative methods embodying the principles of the present disclosure. Similarly, it will be appreciated that any flow charts, flow diagrams, and the like represent various processes which may be substantially represented in computer readable medium and so executed by a computer or processor, whether or not such computer or processor is explicitly shown.
DETAILED DESCRIPTION
[0020] The invention will now be described with reference to the accompanying drawings and embodiments which do not limit the scope and ambit of the invention. The description provided is purely by way of example and illustration.
[0021] One or more embodiments are provided so as to thoroughly and fully convey the scope of the present invention to the person skilled in the art. Numerous details are set forth, relating to specific components, and methods, to provide a complete understanding of embodiments of the present invention. It will be apparent to the person skilled in the art that the details provided in the embodiments should not be construed to limit the scope of the present invention. In some embodiments, well-known processes, well-known apparatus structures, and well-known techniques are not described in detail.
[0022] The terminology used, in the present invention, is only for the purpose of explaining a particular embodiment and such terminology shall not be considered to limit the scope of the present invention. As used in the present invention, the forms "a,” "an," and "the" may be intended to include the plural forms as well, unless the context clearly suggests otherwise. The terms "comprises," "comprising," “including,” and “having,” are open ended transitional phrases and therefore specify the presence of stated features, integers, steps, operations, elements, modules, units and/or components, but do not forbid the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. The particular order of steps disclosed in the method and process of the present invention is not to be construed as necessarily requiring their performance as described or illustrated. It is also to be understood that additional or alternative steps may be employed.
[0023] Figure 1 illustrates a schematic view of a hydrostatic continuous sterilizer apparatus with vertically orientated tower sections according to the invention. In Figure 1 the sterilizer apparatus in its entirety has been given the reference numeral 1. The apparatus 1 comprises a number of tower sections 2 which are placed adjacent to each other. The tower sections 2 are filled with heated or cooled process media and form heating and cooling chambers 3. Some of the tower sections 2 are filled with fluid columns such that an increased pressure can be obtained with high temperature damp phases in adjacent tower sections 2. An endless conveyor 4, which here is formed by two interspaced endless chains, runs meandering with partly straight, vertically orientated track sections through the respective chambers 3. The tower sections 2 are connected to each other by means of upper and lower U-turn sections 5, 6. Guiding wheels 7 are provided in the upper U-turn sections 5 for guiding the conveyor 4 along. In the lower U-turn sections 6 no guiding wheels are provided. There the conveyor 4 can be moved as free hanging loops. Elongated stainless steel product carriers 10 are fixedly connected to the chains of the conveyor 4. Each carrier 10 comprises an outer first side wall 11, an intermediate second side wall 12 and an outer third side wall 12 which extend parallel to each other in a horizontal direction. Partition walls 14 extend in a vertical direction in between the side walls 11, 12, 13. Furthermore a bottom wall 15 is provided which extends in a horizontal direction. Together the side walls 11, 12, 13, the partition walls 14 and the bottom wall 15 delimit a first and second row of rectangular pocket- like insertion spaces 17 a, 17 b. Each insertion space 17 a, 17 b has an insertion opening 18 a, 18 b opposite the bottom wall 15. According to the invention the first and second side walls 11, 12 are provided with primary and secondary slits 20, 21, which here are formed as U-shaped cut-outs. The slits 20, 21 open out towards the insertion openings 18 and extend in a so-called insertion direction X towards the bottom wall 15. An inlet station 24 is positioned at a right side of the apparatus 1. An outlet station 25 is positioned at a left side of the apparatus1. During use the conveyor 4 gets driven to transport the carriers 10 at a substantially constant speed through the respective chambers 3 from the inlet station 24 towards the outlet station 25. At the positions of the stations 24, 25 the carriers 10 can temporarily be held at a standstill such that flexible food packages 27 can be placed in or taken out of the insertion spaces 17. In order to be able to obtain this intermittent transport of the carriers 10 past by the stations 24, 25, the conveyor 4 has the freedom to form bigger or smaller free hanging loops 4 a, 4 b in front of the stations 24, 25. The inlet station 24 is provided with a conveyor belt 30 a for moving the flexible food packages 27 towards the first row of insertion spaces 17 a of a carrier 10 which has been stopped in front of it, and a conveyor belt 30 b for at a same time moving the flexible food packages 27 towards the second row of insertion spaces 17 b of another carrier 10 which has been stopped in front of it. At the ends of the belts 30 a, 30 b, first operating members 31 a, 31 b are provided. Each operating member 31 comprises two vacuum bars 32 forming portions of a load bearing organ or element at the end of which suction heads 33 are provided. The assemblies of the vacuum bars 32 and suction heads 33 can be moved back and forth in the insertion direction X, which here is horizontally directed, into and out of the insertion spaces 17. For this operable translation means 34 are provided. When operated, the suction heads 33 are able to pick up the flexible food packages 27 from the respective belts 30 and then carry them freely floating into the respective rows of insertion spaces 17. During this movement the vacuum bars 32 get to project through the slits 20, 21 of the carrier 10 that gets loaded.
[0024] Figure 2 illustrates a schematic view of phases of thermally processing packaged food products in accordance with various embodiments herein. A process of thermally processing packaged food products can include phases of initial processing 102, a heating phase 104, and post-heating processing 106. It will be appreciated that each of these phases can include multiple steps. By way of example, the initial processing phase 102 can include steps of pressurizing, preheating, placing of packaged food products in trays or carriers, immersing the packaged food products in a fluid (such as a liquid including, but not limited to, water, or a gas), etc. Further, the heating phase 104 can include steps of applying electromagnetic wave energy (such as microwave and/or radiofrequency waves), providing temperature equilibration time while electromagnetic wave energy is withheld or substantially attenuated, holding the packaged food product at a target temperature for a specific amount of time (e.g., a “hold” step or phase), and the like. The post-heating processing phase 106 can include steps of cooling the packaged food product down, depressurizing the packaged food product, removing packaged food products from trays or carriers, stacking packaged food products, and the like. It will be appreciated that the foregoing only serves as examples of steps that can be performed and that additional steps or fewer steps can be performed at each phase in various embodiments.
[0025] Figure 3 illustrates a general flowchart of improved methods for controlling contamination of vacuum-sealed food products. A food with a food surface and a heat-sealable package having a package cavity for holding the food are provided. The surfaces of the food is treated with both a thermal surface treatment and an antimicrobial solution, preferably within the package cavity. Preferably, the food surfaces are first exposed to a thermal surface treatment and then the antimicrobial treatment. More preferably, the thermal surface treatment and antimicrobial treatments are incorporated into a web packaging system line. It is not necessary that the entire exterior surface of the food product is covered with the antimicrobial solution. The package is then vacuum sealed over the food and the vacuum-sealed food product is then stored under conditions that allow the antimicrobial solution to cover the surface of the food, thus forming the vacuum-sealed food product. The general process of the present invention as incorporated into a web packaging system is illustrated in FIG. 3. In a first step, a package cavity for holding the food product is formed using conventional techniques from the lower web film material. The food product to be treated is then placed into the package cavity. The food product is subjected to a thermal surface treatment and an antimicrobial treatment. The thermal surface treatment can be carried out before, essentially at the same time, or after the antimicrobial treatment. Preferably, the thermal surface treatment is first, followed immediately (i.e., within a few seconds) by the antimicrobial treatment. Generally, thermal surface treatment is carried out by exposing the surface of the food product to steam for a short time period (generally less than about 2 seconds). In another preferred embodiment, the thermal surface treatment step also includes, or is immediately followed by, a step to remove water that may have condensed on the food surfaces followed by application of an effective amount of an antimicrobial solution to the surface of the food product and/or into the package cavity. After adding the upper web film material, the package containing the treated food product is then vacuum sealed. During vacuum sealing, the package shrinks around the food product and the antimicrobial solution is uniformily dispersed over the food surfaces. The combination of thermal surface treatment and antimicrobial treatment are effective for killing or inactivating essentially all pathogenic contamination in the vacuum-sealed product.
[0026] The foregoing description of the invention has been set merely to illustrate the invention and is not intended to be limiting. Since modifications of the disclosed embodiments incorporating the substance of the invention may occur to person skilled in the art, the invention should be construed to include everything within the scope of the invention.

, Claims:We claim:
1. An apparatus for thermally processing food packages, comprising:
a. heating chambers;
b. cooling chambers;
c. An endless conveyor system configured to traverse through said heating chambers and cooling chambers; and
d. A plurality of product carriers connected at interspaced positions along said endless conveyor system, wherein said product carriers are adapted for accommodating food packages.
2. The apparatus of claim 1, further comprising:
a. Temperature control means for regulating the temperature within said heating chambers and cooling chambers; and
b. Conveyor control means for controlling the speed and direction of the endless conveyor system.
3. The apparatus of claim 1, wherein said product carriers are adjustable in size to accommodate food packages of varying dimensions.
4. The apparatus of claim 1, wherein said heating chambers are equipped with heating elements capable of providing precise and uniform heat distribution.
5. The apparatus of claim 1, wherein said cooling chambers comprise cooling elements for rapid and controlled cooling of food packages.
6. The apparatus of claim 1, wherein the endless conveyor system is configured to transport food packages in a continuous loop.
7. A method of thermally processing a packaged food product, comprising the steps of:
a. Placing a packaged food product, comprising a hermetically sealed package and a food material disposed within the package, onto a product carrier located on an endless conveyor system within a heating chamber of an apparatus for thermally processing food packages; and
b. Subjecting the packaged food product to a controlled thermal treatment within the heating chamber to achieve desired processing parameters.
8. The method of claim 7, further comprising:
a. Transferring the packaged food product from the heating chamber to a cooling chamber within the apparatus for thermally processing food packages; and
b. Subjecting the packaged food product to controlled cooling within the cooling chamber.
9. The method of claim 7, wherein the controlled thermal treatment comprises one or more of pasteurization, sterilization, or cooking of the food material within the hermetically sealed package.
10. The method of claim 7, wherein the packaged food product is conveyed through a series of heating chambers and cooling chambers on the endless conveyor system to achieve multiple thermal processing stages.