Abstract:
The disclosure relates to a transport container for accommodating products during a high-pressure treatment of these products. By means of the transport container, the products can be transported into and out of a chamber in which they are high-pressure treated. The transport container comprises a lower component and an upper component which are adapted to be connected to one another, the lower component as well as the upper component being configured for accommodating at least one product.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims foreign priority benefits under 35 U.S.C. §119(a)-(d) to German patent application number DE 102009042094.0, filed Sep. 18, 2009, which is hereby incorporated by reference in its entirety. 
       TECHNICAL FIELD 
       [0002]    The present disclosure relates to a transport container for accommodating products during a high-pressure treatment of these products. 
       BACKGROUND 
       [0003]    Foods are subjected to chemical and biological processes which change their composition and which may also produce substances that are harmful to health. Foods may, for example, oxidize or they may be modified by enzymes and microorganisms, e.g. mould fungi. These processes must be prevented or at least delayed within the desired shelf life so that foods can be eaten safely by the consumer and so that they can be transported, and will have the longest possible shelf life. 
         [0004]    One possibility of doing this is to add large amounts of sugar or salt to the respective foods or to dry them so as to remove water therefrom, whereby the development of microorganisms, such as mould fungi or bacteria, will be impeded. Also an addition of alcohol or vinegar, an addition of preservatives as well as cooling slowdown the development of microorganisms and reduce the activity of enzymes. Furthermore, also a heat treatment can be carried out so as to kill microorganisms and deactivate harmful enzymes. During pasteurization the foodstuff is heated to a temperature below 100° C. for a certain period of time. The comparatively resistant bacterial spores remain, however, germinable during such treatment, and there is the risk that also important nutrients and flavours will be destroyed by the heat treatment. 
         [0005]    Another method of increasing the shelf life of foods consists of filling the foods into a gas-tight package and evacuating the package before it is closed. If necessary, the package may also have added thereto a protective gas or protective gas mixtures, e.g. with nitrogen or CO 2 . Also the expulsion of air, e.g. of oxygen, has the effect that the activity of enzymes or microorganisms is slowed down. 
         [0006]    A method which has hitherto hardly been used, at least not on an industrial scale, is the high-pressure treatment of foods. In the case of this method, a foodstuff, which has normally already been packaged, is subjected to very high pressures of typically 400 MPa to 600 MPa for a certain period of time, e.g. for a few minutes. These high pressures have the effect that harmful microorganisms in the foodstuff will be destroyed and killed, whereas comparatively small molecules, such as vitamins, which determine the flavour and the nutritional value of the foodstuff, are hardly influenced by the high-pressure treatment. As regards meat products, the shelf life may thus be increased e.g. by a factor of 6 to 10 in comparison with the non-treated product. 
         [0007]    In comparison with heat treatment, high-pressure treatment has various advantages. For example, there is hardly any change in flavour and the vitamin content of the foodstuff is, after a high-pressure treatment, in some cases more than twice as high as after a heat treatment. In addition, some heat-sensitive products, e.g. seafood, do not allow any heat treatment at all. Pathogenic germs, such as listeria, can be killed reliably, so that food safety will be increased. High-pressure treatments can, however, also be used for purposefully influencing the internal structure of the food, so that new product possibilities, e.g. through gelatinizing of fruit preparations without heat, are obtained. Finally, the high-pressure treatment technology has already been acknowledged in many countries as (food) safe. 
         [0008]    When packaged food is high-pressure treated, the process conditions may lead to problems with the packaging. Optically disadvantageous modifications as well as damage may occur. Problems arise especially in the case of packages containing a protective gas atmosphere, due to the highly compressible amount of gas in the package. This is also a reason for the fact that, up to now, the packages used for high-pressure treatment have predominantly been vacuum packages. 
         [0009]    The deactivation of microorganisms as well as the structural modifications of food components are described e.g. in EP 0 588 010 A1, or EP 0 689 391 B1, EP 0 752 211 B1, EP 1 100 340 B1, DE 42 26 255 A1, or DE 37 34 025 C2, EP 1 112 008 B1, EP 1 201 252 B1, DE 196 49 952 A1, DE 197 38 800 A1, DE 199 39 677 A1 and DE 26 11 389 A1 describe the effects of high-pressure treatments on the microbiological storage life and the safety of food. DE 198 01 031 C2, DE 1 965 36 C1, EP 0 748 592 B1, EP 0 683 986 B1, DE 101 01 958 A1, DE 10 2005 011 868 A1, or WO 2006/097248 A1, describe the application of high-pressure treatments to meat products in particular. 
         [0010]    A plant for subjecting food to a high-pressure treatment is additionally known from WO 2006/129180 A1. In this plant an autoclave is provided, which comprises a high-pressure chamber in which the food is subjected to high pressure. For building up the pressure, the autoclave must be closed. Hence, the plant cannot be operated continuously. In order to increase the throughput of the plant, it is typically operated in a batch processing mode, in which the products are introduced in the autoclave, high-pressure treated and removed from the autoclave in groups. 
         [0011]    In order to be able to load and unload the autoclave more rapidly and to reduce thus the cycle time, the products to be treated are normally filled into a transport container. As soon as the high-pressure chamber is free, one or possibly a plurality of transport containers can be conveyed into the high-pressure chamber, e.g. by moving them by means of a slide. After the high-pressure treatment, the transport containers are removed from the autoclave, e.g. by pushing them out on the side located opposite to the inlet opening. 
         [0012]    The transport containers, sometimes also referred to as cartridge, normally have a circular cross-section and a cylindrical shape so as to match with the normally cylindrical inner wall of the high-pressure chamber.  FIG. 5  shows a cross-section of a conventional transport container  100 . The transport container  100  has an outer wall  102  that imparts a circular cross-section thereto. A filling opening  103  extends over almost the entire length of the transport container  100  on the upper side thereof. Through this filling opening  103 , products  104  can be filled into the transport container  100  and removed from said transport container  100 . 
         [0013]    At least when the transport container is filled by a robot, the products  104  can only be stacked vertically directly below the filling opening  103 , but not in the lateral areas covered by the outer wall  102 . In order to prevent the products  104  from slipping into these areas, which are covered by the upper portions of the outer wall  102 , interior walls  105  can be provided, on which the products  104  abut. 
         [0014]    The conventional transport container is disadvantageous insofar as, at least when it is filled by a robot, a substantial part of its interior volume cannot be utilized for accommodating products therein. In addition, another part of the theoretically utilizable filling volume is not filled, since the filling level must not exceed the edge of the opening  103 . 
       SUMMARY 
       [0015]    It is an object of present disclosure to provide a transport container which is used for accommodating therein products during a high-pressure treatment and which, with the aid of means having the simplest possible structural design, has been improved in such a way that, although the necessary stability is guaranteed, a higher filling level will be achieved, even if the transport container is filled by a robot. 
         [0016]    A transport container according to an embodiment of the present disclosure is characterized in that it comprises a lower component and an upper component which are adapted to be connected to one another, the lower component as well as the upper component being configured for accommodating at least one product. This multipart design of the transport container contradicts the conventional conviction that the transport container must be configured as an integral component, since it would otherwise not be able to resist the extreme pressures acting thereon during high-pressure treatment. However, surprisingly enough, it has turned out that also a multipart transport container is able to resist the high pressures, provided that it has a suitable structural design. The subdivision of the transport container into a lower component and an upper component may provide a plurality of advantages:
       Both components can be filled completely, the normally non-utilizable space does not exist here.   The upper component and the lower component can be loaded or unloaded simultaneously, so that the time required for loading and unloading will be reduced.   In comparison with conventional loading, the opening available for loading and unloading is increased in size, so that loading and unloading can be executed more easily.   Due to the large cross-section of the accessible opening, individual product retaining means/interior walls can easily be inserted.   Also products of different sizes can be inserted as packing patterns in correspondence with the radius of the containers.   When the transport container is divided into an upper component and a lower component in a suitable manner, there will be no areas that are covered by the edge of the filling opening. It follows that, even if the container is filled by a robot, the whole space in the lower component and in the upper component can be filled with products in an ideal, product-specific packing pattern, so that the degree of filling and the efficiency of the high-pressure plant will be increased substantially.       
 
         [0023]    It is imaginable that the lower component and the upper component are fully separated from one another during loading or unloading or at least for the purpose of maintenance and cleaning and are interconnected only during transport and high-pressure treatment. The transport container will, however, be easier to handle when the lower component and the upper component are permanently interconnected such that they are movable relative to one another, since the transport container will in this case be easier to handle as a whole and can, as a whole, e.g. be conveyed more easily from the unloading station back to the filling station. 
         [0024]    According to one embodiment, the lower component and the upper component complement each other so as to define a cylindrical shape of the transport container in its entirety, so that the transport container will adapt itself to the shape of the interior of the high-pressure chamber in the best possible way and utilize the volume available as effectively as possible. 
         [0025]    According to a variant of the present disclosure, the lower component and the upper component each have a semicylindrical shape. This has the effect that, on the basis of a cylindrical shape of the transport container in its entirety, the filling opening available for each of the two components will be maximized. It follows that the whole diameter of the transport container, which is cylindrical in shape in its combined condition, is available for loading and unloading. 
         [0026]    Irrespectively of whether the lower component and the upper component are adapted to be releasably connected to one another or are permanently connected to one another, they can be connected to one another via a first hinge in the interconnected condition. This hinge allows a simple movement for closing the transport container by simply swivelling the lower component and the upper component relative to one another about the first hinge. 
         [0027]    With respect to the high-pressure treatment, it will be advantageous when the first hinge is lubricant-free so as to prevent the lubricant from being expelled from the hinge during the high-pressure treatment. It follows that materials suitable for the hinge are e.g. so-called “self-lubricating” plastics. 
         [0028]    At least one retaining element may be provided for retaining and securing in position products accommodated in the upper component and/or in the lower component. In the case of the transport container according to the present invention it may especially be necessary to swivel or tilt the lower component or the upper component so as to close the transport container. During such swivelling movements, the at least one retaining element will prevent the products from being displaced within the upper component or the lower component. 
         [0029]    It is imaginable to releasably attach the at least one retaining element to the lower component and/or the upper component as well as to permanently attach the retaining element to said lower and/or upper components. Both variants may have advantages. A releasable mode of attachment may perhaps enlarge the opening available for filling in the products. A permanent mode of attachment may make it easier to uniformly handle the transport container in its entirety and it may facilitate e.g. automated handling of the same. 
         [0030]    In particular in the case of a permanent mode of attachment, the at least one retaining element may be attached to the lower component or to the upper component via a second hinge. In this case, the retaining element could be moved by a simple swivelling movement about the second hinge so as to close the lower component and the upper component, respectively, and so as to reliably retain the products in the component in question. 
         [0031]    The movements required for closing the transport container can be executed more easily when the swivelling axis defined by the first hinge extends parallel to the swivelling axis defined by the second hinge. 
         [0032]    Alternatively, the at least one retaining element may be adapted to be attached to, or may be permanently attached to the lower component and/or the upper component via a rail. In this case, the retaining element would be displaceable along the rail so as to open or close the lower component and the upper component. In the case of an automated operation of the high-pressure treatment plant, this displacement may be executable more easily than a swivelling movement about a hinge. 
         [0033]    According to one embodiment, the at least one retaining element is adapted to be releasably secured in position on the lower component and/or on the upper component, so that it is no longer able to change its position relative to the associated lower component or upper component and will thus be able to reliably retain the products. 
         [0034]    When the retaining element is provided with at least one opening through which high-pressure medium can flow, pressure compensation between the lower component and the upper component can take place in an advantageous manner, so that the products in both parts of the transport container will be treated with the same pressure. A uniform result of the treatment will be accomplished in this way. 
         [0035]    According to one variant of the present disclosure, the retaining element in its entirety, or at least certain areas thereof are configured as a grating. The grating is advantageous insofar as it has a comparatively low weight, comprises large openings through which the high-pressure medium can flow, and is simultaneously able to retain the products in a very reliable manner. 
         [0036]    With respect to an automated mode of operation and with respect to the dimensioning of the high-pressure treatment plant, it proved to be advantageous when the transport container has a holding capacity in the range of 50 litres to 600 litres. 
         [0037]    In the following, two advantageous embodiments of the invention will be explained in more detail on the basis of a drawing. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0038]      FIG. 1  shows a perspective view of a first embodiment of the transport container according to the present disclosure at an open position; 
           [0039]      FIG. 2  shows the transport container according to  FIG. 1  at a closed position; 
           [0040]      FIG. 3  shows a second embodiment of a transport container according to the present disclosure at an open position; 
           [0041]      FIG. 4  shows a cross-section through a closed and filled transport container according to the present disclosure; and 
           [0042]      FIG. 5  shows a cross-section through a filled conventional transport container. 
       
    
    
     DETAILED DESCRIPTION 
       [0043]    Identical components are provided with identical reference numerals in all the figures. 
         [0044]      FIG. 1  shows a first embodiment of a transport container  1  according to the present disclosure at an open position. The transport container  1  comprises a lower component  2  and an upper component  3 , each having a semicylindrical shape. The lower component  2  and the upper component  3  may consist e.g. of a high pressure-resistant plastic material. The lower component  2  and the upper component  3  are connected to one another on their longitudinal sides via a first hinge  4 . The first hinge  4  defines a first swivelling axis  5  about which the upper component  3  can be swivelled relative to the lower component  2  so as to close the transport container  1 . 
         [0045]    The lower component  2  as well as the upper component  3  are provided with approximately semicircular end faces  6  at both ends thereof, when seen in the longitudinal direction. The end face  6  is flat so that a slide (not shown) can act more easily on a closed transport container  1  so as to push the transport container into and out of a high-pressure plant. Each of the flat end faces  6  has provided therein openings  7  through which high-pressure medium can enter the closed transport container  1  so that the products accommodated in the transport container  1  are subjected to high pressure. If necessary, the cylinder sides may be provided with openings  7  as well. 
         [0046]    Via a second hinge  8 , the upper component  3  has secured thereto a retaining element  9  implemented as a grating. The second hinge  8  defines a second swivelling axis  10  about which the retaining element  9  can be swivelled relative to the upper component  3 . In particular, the retaining element  9  can be swivelled from the open position shown in  FIG. 1  by 180° counterclockwise so that the outer edge  11  of the retaining element  9  will abut on the first hinge  4 . In the area of the first hinge  4  and on the outer edge  11  of the retaining element  9 , a closure member (not shown) can be provided, by means of which the retaining element  9  can be fastened releasably in the position in which it closes the upper component. The meshes  12  of the grating-shaped retaining element  9  define openings through which the high-pressure medium can flow freely between the lower component  2  and the upper component  3 , so that pressure compensation is accomplished between the two components of the transport container  1 . 
         [0047]      FIG. 2  shows the transport container  1  according to  FIG. 1  in a closed position. In the open condition, both the lower component  2  and the upper component  3  of the transport container  1  were first filled with products  13 .  FIG. 2  shows, exemplarily, three rectangular sectioned products  13 , such as packaged foods, accommodated in the upper component  3 . Also the other areas of the lower component  2  and of the upper component  3  have been filled with products  13 —as far as the geometry of the products  13  allows such filling. Subsequently, the retaining element  9  has been swivelled about the second swivelling axis  10  and moved to a closed position where it is secured in position by the closure member (not shown). Finally, the upper component  3  has been swivelled about the swivelling axis  5  defined by the first hinge  4 . The transport container  1  is thus closed and assumes the cylindrical shape shown in  FIG. 2 . In the closed position, the upper component  3  can be secured in position on the lower component  2  by a fastener so as to prevent the transport container  1  from being opened unintentionally. 
         [0048]      FIG. 3  shows a second embodiment of a transport container  1  according to the present disclosure. Also in this embodiment the transport container  1  comprises a lower component  2  and an upper component  3 , each of said components being semicylindrical in shape. For the sake of clarity, the openings  7  through which the high-pressure medium flows are not shown. 
         [0049]    A first difference in comparison with the first embodiment is that, in the second embodiment, the lower component  2  and the upper component  3  are not permanently connected to one another, but they are adapted to be releasably interconnected. In  FIG. 3 , they are shown in a condition in which they are separated from one another and in which the two components  2 ,  3  are freely accessible with their filling opening  14  facing upwards, so that products  13  can be filled into said components  2 ,  3  or removed therefrom. In the closed position of the transport container shown in  FIG. 2 , the two components  2 ,  3  are secured in position on one another by a fastener. 
         [0050]    A second difference in comparison with the first embodiment is that both the lower component  2  and the upper component  3  now have a retaining element  9  of their own, said retaining element  9  being again grating-shaped. Finally, another difference is to be seen in that both the lower component  2  and the upper component  3  each have a rail  15 . The respective retaining element  9  can be inserted into the rail  15  of the associated component  2 ,  3  of the transport container  1  in the direction of the arrow P so as to cover the filling opening  14  and secure thus the filled-in products  13  in position in the respective component  2 ,  3  of the transport container  1 . In its closed position, the retaining element  9  can be held on the respective component  2 ,  3  of the transport container  1  either by a closure member or only by gravitation. When the two individual components  2 ,  3  of the transport container  1  have been closed, they are placed one on top of the other in such a way that the closed, cylindrical transport container  1  according to  FIG. 2  is obtained. 
         [0051]      FIG. 4  shows a cross-section through the closed transport container  1  filled with products  13 . Whereas the products  13  in the lower component  2  rest on the bottom of said lower component  2 , the products  13  in the upper component  3  of the transport container rest on the retaining element  9 . The retaining element  9  thus holds the products  13  in the upper component  3 . Spaces  16  between the products allow the high-pressure medium to pass through and—in cooperation with the openings  12  in the retaining element  9 —they provide pressure compensation in the transport container  1  in its entirety. 
         [0052]    A comparison with  FIG. 5  shows clearly that the transport container  1  according to the present invention achieves, in the case of automated filling, a much higher degree of filling than the conventional transport container  100 . Whereas the transport container  1  according to the present invention accommodates twenty two products, the conventional transport container  100 , which has the same external dimensions, is only able to accommodate seventeen products. Due to the higher degree of filling, the transport container  1  according to the present invention provides a much higher efficiency and a much higher throughput in a high-pressure treatment plant. 
         [0053]    Starting from the above-described embodiments, the transport container  1  according to the present invention can be modified in many ways. In particular, arbitrary combinations are imaginable between lower and upper components  2 ,  3  which are secured to one another releasably or permanently, retaining elements  9  which are secured, releasably or permanently, to one of said lower and upper components  2 ,  3  or to both of them, as well as retaining elements  9  which are movably supported on the respective component  2 ,  3  via a hinge  8  or a rail  15 . In addition, variants are imaginable in the case of which additional subdivisions or possibly removable partitions for securing the products  13  in position are provided in the lower component  2  or in the upper component  3 , or in the case of which the retaining element  9  has a different structural design. For example, a net or a group of chain links may be provided as a retaining element  9 , or the retaining element  9  could be largely closed and could have provided therein only a small number of openings  12  through which the high-pressure medium can flow. 
         [0054]    Instead of a hinge  4 , also other suitable systems, e.g. plug connections, may be used for interconnecting the lower component  2  and the upper component  3  of the transport container  1  permanently or releasably. 
         [0055]    In addition, it is also possible to provide spring-biased safety elements on the lower component  2 , on the upper component  3  and/or on the retaining element  9  so as to retain the products  13  more reliably in position when an only partially filled transport container  1  is being conveyed and/or during the high-pressure treatment itself. An only partially filled transport container  1  may occur e.g. during a change of batches, when the production line is run empty, or when the individual packages have a disadvantageous geometry as regards filling. The safety elements will then guarantee that the products  13  will neither shift nor tilt so that their position in the transport container  1  will not change between loading and unloading of the transport container  1 . This makes automated unloading of the transport container  1  much easier. Such a safety element may e.g. be provided in the form of a board which rests on the retaining element  9  via one or a plurality of pressure springs and which thus forces the products  13  contained in the lower component  2  of the transport container downwards. The safety elements may, however, also be acted upon by a spring vertically upwards or in a lateral direction. 
         [0056]    While embodiments of the invention have been illustrated and described, it is not intended that these embodiments illustrate and describe all possible forms of the invention. Rather, the words used in the specification are words of description rather than limitation, and it is understood that various changes may be made without departing from the spirit and scope of the invention.