CA2800692A1 - Method and device for the portioned packaging of a food mass - Google Patents

Abstract

The invention relates to a method for the portioned packaging of a food mass that is at least substantially incompressible, in particular of processed cheese, and that is filled as a flowable mass into a tubular sleeve comprising a thermoplastic plastic film, wherein the thermoplastic plastic film of the sleeve enclosing the food mass is deformed in a mold into individual units each defining a portion by forcing the food mass out of sealing areas, such that the units arranged one behind the other are delimited with respect to each other by means of sealing in the sealing area and are subsequently separated from one another.

Description

-1- BD/Kr 10072 Method and Device for the Portioned Packaging of a Food Mass The invention relates to a method for the portioned packaging of an at least substantially incompressible food mass, of processed cheese in particular, which is filled as a flowable mass into a tubular wrapping comprising a thermoplastic plastic film. The invention further relates to a device for carrying out the method.

Various methods are known for the portioned packaging of such a food mass.
In some methods, the food mass is poured into shells, which are preformed of a stable film, more particularly plastic. The individual shells filled with the food mass are subsequently closed and separated from one another. The disadvantage of this solution is that a separate tool or even a separate machine is required for each working step, more particularly preshaping, filling, closing and separating. In addition, the portioned filling of preshaped packages with such a food mass is relative complex in terms of adjustment.

Basically, three methods are known for packaging processed cheese: It is known, for instance, to bring the processed cheese into slice form and to stack these individual slices on top of one another, "slice on slice". It is also known to make individually packaged slices ("individual wrapped slices", IWS). To this end, a film tube is filled with processed cheese and smoothed into a strip before it is subdivided into individual slices by displacement, sealing and cutting. Another way to package processed cheese is to enclose individual portions in aluminum foil. Such portions are known as triangular shapes, a plurality of which is placed together in a circle in one common outer packaging.
The individual portions can be provided with a string, as the tear-open aid, which cuts through the foil. Such portioned packaging in aluminum foil is relatively complex.

-2- BD/Kr 10072 The problem addressed by the present application is therefore that of providing a method for the portioned packaging of a food mass, more particularly processed cheese, in which the individual packages of the food mass can be manufactured in a simple and low-cost manner in various shapes and which are easy for the consumer to handle. A corresponding problem addressed by the invention is that of providing a device for implementing the method.

These problems are solved by a method having the features of claim 1 and by a device having the features of claim 7. Advantageous embodiments are mentioned in the dependent claims.

The significant fundamental idea of the invention is to fill the food mass into a film tube and subsequently deform it by deep drawing while maintaining the presence of the food mass. To this end, the food mass is basically displaced out of regions of the completely filled tube into regions in which deep drawing takes place quasi simultaneously. A separate deep-drawing punch is not required, however. The food mass functions as a punch and presses the film into the mold of the tool. The mass that is excessive in the regions of the displacement finds space in the newly formed regions. To this end, according to the invention, the thermoplastic plastic film of the wrapping enclosing the food mass is reshaped in a mold into individual units, each defining a portion, with displacement of the food mass out of sealing areas. Said units disposed one behind the other in a chain are delimited from one another by way of sealing in the sealing area and are subsequently separated from one another.
Such a unit is also referred to in the following as a cavity filled with the food mass. The cavity defining a portion of the food mass is therefore formed, according to the invention, in the film strip, which is already filled. The flowable food mass enclosed by the film strip thereby completes the shaping of the film layer and assumes the shape of the cavity. The shaping of the film strip and a portioning of the food mass are therefore concomitant.

The method according to the invention makes it possible to manufacture easy-to-handle individual packages in an automated manner. The method can replace the subsequent filling of preformed shells. As a result, the production of - 3 - BD/Kr 10072 individual packages filled with food mass is greatly simplified and product output is markedly increased. Due to the simultaneous shaping of the film tube and the food mass, the method is suitable more particularly for the portioned packaging of processed cheese, since processed cheese is particularly easy to handle because the viscosity thereof can be adjusted via temperature. The method makes continuous production possible. At the same time, it offers high variability in terms of the possible packaging shapes. The cavities can be formed in the filled film strip in nearly any shape and, due to the three-dimensional orientation thereof in particular, they offer a great deal of freedom for product design.

It is particularly advantageous that the shaping of the filled film strip, according to the invention, can be integrated into existing production systems for packaging food masses. It is therefore possible to retrofit or expand previously used machine lines for the new method.

In a preferred embodiment, both film layers of a double-layer film tube filled with food mass are molded. By forming opposing cavities in the double-layer film strip, it is possible to increase the total volume of the individual package that is available. Shaping the double-layer film strip on both sides also makes it possible to obtain a symmetrical design of the top part and the lower part of the individual packaging. For the case of an asymmetrical design, a top part of the forming means is designed smooth, for example, while the lower part comprises shaping cavities.

A vacuum is preferably applied in a forming means to support the formation of the cavities in the film layer. The vacuum induces a type of deep-drawing effect on the film layer. It is applied while the mold segment of the forming means closes in the sealing area of the double-layer film strip. The vacuum is deactivated before the shaping means is opened. The film layer is thereby not only pressed into the mold segment, it is also drawn in via suction. It comes to line the walls thereof and assumes the shape thereof. The vacuum induces a precise molding of the predefined shape by way of the thermoplastic film.

-4- BD/Kr 10072 The food mass is thereby not only displaced out of the sealing areas, it is also suctioned into the mold segments. It follows the shaping of the film layer and fills the mold segment. Only a slight amount of food mass remains in the sealing area due to the combination suction and displacement effect acting on the food mass, thereby simplifying the subsequent sealing of the film layers in the sealing area. It is particularly advantageous when the vacuum is adapted to the food mass in terms of level and duration.

Temporary and local heating of the thermoplastic plastic film supports the formation of the cavities in the film strip. To this end, the regions of the forming means coming in contact with the film to be reshaped are heated.

Thermoplastic plastics of different types and film thicknesses can be processed using the method and the device. Films made of PE, PET and PP are suitable in particular. The preferred film thickness is between 20 pm and 100 pm. The method also makes it possible to use film tubes made of film strips of different materials. Film strips made of thermoplastic plastic and aluminum foil can be combined, for example.

Preferably, a separating segment of the forming means is first moved into the food mass enclosed by the film strip. Said separating segment, which is designed as a type of hold-down device, moves into the production strand before the individual packages are shaped. It therefore delimits the part to be reshaped from the rest of the film tube. This subdivision of the product strand defines the region of the filled film tube that is available for the forming process.
The segment prevents food mass from flowing out of the rest of the production strand into the part of the film strip to be reshaped while the cavities are being formed. It is thereby possible to minimize fluctuations in the volume of the individual packages that are produced.

To ensure that the product strand becomes detached from the forming means, a vacuum is preferably applied to the cavities of the forming means. To this end, it is advantageous to use the vacuum connection to also supply vacuum.
The forming means preferably also comprises a means for sealing the sealing area located between the consecutive hollow shapes. Since the forming means - 5 - BD/Kr 10072 not only forms the cavities in the filled film strip, but also seals the sealing area, this working step can be combined in one tool. It is therefore easier to change the shape of the individual packages. Such shape changes usually involve changing the shape and position of the sealing area between the individual packages. When the packaging shape is changed, the effort required for set up at the packaging system is therefore reduced.

In a particularly preferred embodiment, the sealing area separating the cavities is sealed using ultrasound. Using ultrasound for sealing has the great advantage over sealing using heat that a seam sealed using ultrasound is easier to re-open later, that is, it has better "pealability". In addition, the ultrasound displaces any remaining quantities of food mass out of the sealing area. A product inclusion in the sealing seam is prevented. This ensures uniform strength of the sealing seam. In addition, a product inclusion in the sealing area is perceived by the customer as an impairment of quality. The clean sealing seam increases the appearance of quality of the final product.
The sealing by way of sonotrode and sealing anvil can take place in a separate working step. The forming means itself, more particularly the lateral delimitations of the shaping cavity thereof moving into the sealing area, are preferably designed as a sonotrode. The sealing components are therefore integrated into the forming means.

At the end of the process, the film strip is cut in the sealing area. The packages of food mass, which have been separated from one another, are then fed individually to the further packaging process. The individual working steps of the shaping, sealing and separation of the individual packages are preferably combined in direct succession. In order to retrofit the production system for another packaging shape, it is therefore only necessary to replace the forming means and the separating device. In a particularly preferred embodiment, the separating device is part of the forming means.

In a further particularly preferred embodiment, the food mass is cooled before the filled film strip is shaped. In contrast to pouring a liquid food mass into a preshaped packaging mold, when the cavities are formed according to the invention, the food mass is pressed therein and is preferably also suctioned -6- BD/Kr 10072 therein. The consistency of the food mass is therefore not required to be liquid but merely flowable in order to fill the cavities formed in the film strip.
The food mass has already cooled to a great extent when the cavities are formed in the film layer. It is therefore possible to eliminate complex cooling of the shaped individual package in order to prevent deformations in the further course of the production process, and to eliminate having to fill secondary packages. In order to perform cooling before shaping, the food mass is preferably guided along a cooling path using cooling belts in a manner known per se, or said food mass is directed through a cooling water bath. This ensures uniform cooling of the food mass. The film can be supplied before or after cooling.

In a further particularly preferred embodiment, the edge regions of the two film layers overhanging at a longitudinal sealing seam form an opening tab for opening the package. The two film layers are connected to one another via the longitudinal sealing seam before the cavities are formed. Depending on how the double-layer film strip was placed, it comprises one or two longitudinal sealing seams. If a single film is placed so as to form a double-layer film strip, it comprises a longitudinal sealing seam on one side, which connects the lateral end regions of the two film layers to one another. The variant of a double-layer film strip formed of two film layers comprises longitudinal sealing seams on both sides. The film layers are dimensioned in such a way that film edge regions of the joined film layers overhang after the longitudinal sealing seam is sealed. Pulling the overhanging film edge regions apart first opens the longitudinal sealing seam and, as pulling continues, opens the sealing areas of the individual package. The packaging portion can thereby be easily opened completely and the contents thereof can be removed from the packaging without leaving any traces behind.

The overhanging film edge regions are preferably cut off in such a way that the remaining film edge region of the two film strips has the shape of a tab protruding from the individual package. The tab shape is intuitively recognized by the customer as an opening mechanism for the individual package, and therefore no further instructions on the package are required.

-7- BD/Kr 10072 In a further preferred embodiment, the two-layer film strip is in continuous forward motion. This creates an endless, continuously self-renewing product strand of the filled film strip. Automatic repositioning of the forming means during the forming process makes it possible to continuously manufacture individual packages of the food mass with correspondingly high product output.
The method or the device according to the invention makes it possible to manufacture packaging portions in highly diverse shapes. In addition to the popular cheese wedge shape familiar to the consumer, it is also possible to form square or rectangular cavities in the film strip. The cavities can be formed in one film strip or in both film strips symmetrically or asymmetrically with respect to one another. A further variable is the material that is selected for the films. The possibilities for variation therefore range from a symmetrical package having film strips made of plastic that are identically shaped on both sides and a sealing seam encircling the package in the center, to a package shaped on one side and having an off-center sealing seam, the non-reshaped aluminum foil strip of which closes the package in the manner of a cover.

In contrast to the known packages made of aluminum foil, the use of a transparent plastic film provides the consumer with a direct view of the packaged product. Additions such as herbs or nuts need not be only indicated on the label; the customer can even see them in the product itself. By coloring the film strip specifically according to type, it is preferably possible to identify the contents of the package.

An embodiment of the invention is described in the following by reference to figures 1 to 11. Shown are Figure 1: shows an opened forming tool with a still undeformed production strand of the enclosed food mass;

Figure 2: shows a sectional drawing along the line A-A of figure 1;

Figure 3: shows the closing forming tool as it begins to move into the product strand;

Figure 4: shows a sectional drawing along the line B-B of figure 3;

-8- BD/Kr 10072 Figure 5: shows the closing forming tool with a closed separating segment that has penetrated the product strand;

Figure 6: shows a sectional drawing along the fine C-C of figure 5;
Figure 7: shows the forming tool after completion of the forming process;
Figure 8: shows a sectional drawing along the line D-D of figure 7;
Figure 9: shows a hold-down device of the forming tool;

Figure 10: shows a base plate of the forming element comprising mold segments;

Figure 11: shows a schematic representation of the various shaping steps on the product strand.

Figures 1 to 8 show a forming means according to the invention in the form of a forming tool 1. The forming tool is depicted in a series of various phases of the process of forming the film strip 2 filled with food mass.

In figures 1 and 2, the forming tool 1, which comprises an upper part 3 and a lower part 4, is open and has no contact with the production strand of the film strip 2. The upper part 3 and the lower part 4 of the forming tool 1 are oriented toward the top side and the underside, respectively, of the production strand and are disposed opposite one another in a mirror-image manner. The upper part 3 and the lower part 4 are of substantially identical construction, and so information regarding features or movements of one part 3, 4 of the forming tool 1 always also relate to the other part 3, 4 in a mirror-image manner.

Each part 3, 4 of the forming tool 1 comprises a base plate 5 and a mold plate 6, which is disposed on the side of the base plate 5 facing the production strand and is detachably connected thereto. A separating segment 7, as a type of hold-down device, projects from the part 3, 4 in the direction of the production strand. The base plate 5 and the hold-down device are connected to one another via a guide B. The guide 8 is preloaded via springs 9 and permits -9- BD/Kr 10072 the hold-down device to move relative to the base plate 5. The base plate 5 further comprises a vacuum and compressed air connection 10, which is connected to a hollow chamber 11 incorporated in the mold plate 6. A vacuum is applied at a mold segment of the forming tool 1 via the hollow chamber 11.
The hollow chamber 11 is delimited on the product-strand side by an insertable base 12, which is separated from the base plate 5 by way of a spacer sleeve 13. The insertable base 12, in combination with webs 14 of the mold plate 6 protruding laterally from the insertable base 12 in the direction of the production strand, forms a mold segment 15, which is open toward the filled film strip 2 and into which the film strip 2 is formed. The mold segment 15 therefore forms a female mold for the film strip 2 filled with the food mass 16.

The film strip 2 filled with food mass 16 comprises two film layers 17, 18, which are connected to one another on both sides via longitudinally extending sealing seams 19. Film edge regions 20 protrude from the double-layer film strip 2 along the longitudinal sealing seams 19. The mold plate 6 comprises two temperature-controlled cartridge heaters 21 for the temporary and local heating of the thermoplastic film layer 17, 18.

Figures 3 and 4 show the forming tool 1 at the beginning of the closing process. At this point in time, an outer surface of the hold-down device 7 is located at the level of the still non-deformed product strand of the filled film strip 2. The hold-down device 7 comprises a heating element, which is not shown here, in order to heat the thermoplastic plastic film to be deformed. The heated hold-down device 7 is offset on either side with respect to the enclosed food mass 16 and is disposed above the film edge regions 20 of the double-layer film strip 2. To prevent the film edge region 20 from becoming heated by contact with the heated hold-down device 7, the hold-down device 7 comprises a longitudinally extending insulating element 21 on both sides, which externally adjoins a longitudinal web 22 of the hold-down device protruding in the direction of the production strand. The hold-down device 7 also comprises two cross webs, which are not shown here and extend transversely overall with respect to the production strand, said cross webs contacting the double-layer film strip 2 in this position of the closing process.

_10- BD/Kr 10072 In figures 5 and 6, the hold-down devices 7 are closed by the upper part 3 and the lower part 4 of the forming tool 1, and therefore the film edge regions 20 are held between the longitudinal webs 22 and the insulating elements 21. In this position of the forming tool, the cross webs of the hold-down devices 7 have fully penetrated the product strand. The cross webs, which are disposed at the beginning and at the end of the hold-down device 7 relative to the production strand, therefore seal the region of the production strand to be deformed by the forming tool 1.

Figures 7 and 8 show the forming tool 1 with the upper part and the lower part 3, 4 completely closed. When the vacuum is applied into the mold segments 15, the pressure plate 5, together with the mold plate 6, in both parts 3, 4 moves in the direction of the production strand. The heated webs 14 of the mold plates 6 thereby penetrate the product strand in opposition, deform the thermoplastic film layer 17, 18 at this point, and displace the food mass 16 located in this region of the product strand. The food mass 16 presses the film layers 17, 18 into the mold segments 15. The food mass 16, which is at least nearly incompressible, functions as a deep-drawing punch that presses the film layer 17, 18 into the mold segments 15. Cavities 23, each defining a portion of the food mass 16 and following one another individually, are thereby formed in the film layers 17, 18.

In addition, the film layer 17, 18 is drawn against the heated insertable base via the vacuum present in the mold segment 15. The vacuum is applied after the hold-down device 7 has fully penetrated the product strand. The strength and the duration of the vacuum are adapted to the food mass. The food mass 16, which is still flowable and has been displaced from the region of the closing webs 14, completely fills the cavity 23 that forms.

In the exemplary embodiment described here, two opposed cavities 23 form a single portion of the food mass 16 in each case. The shape of the portion is defined by the mold segments 15 of the parts 3, 4.

The mutually impacting webs 14 of the mold plates 6 press the film layers 17, 18 together and define a sealing area 24 encircling the individual packages.

_11- BD/Kr 10072 The sealing area 24 is sealed using an ultrasonic sealing method known per se in order to permanently shape the individual packages. The webs 14 function as a sonotrode (welding horn), and therefore the sonotrode and sealing anvil sealing components are integrated in the forming tool. The two working steps can also be carried out by two tools that follow one another in the production process.

After the individual packages are fully formed, the vacuum in the mold segment 15 is no longer maintained. The parts 3, 4 of the forming tool move apart from one another and release a strand of fully formed, consecutive individual packages of the food mass 16.

During the method steps described by reference to figures 1 to 8, the forming tool moves at a speed v, which corresponds to the speed vp of the continuously moving production strand. After opening, the forming tool 1 moves along the production strand opposite the conveyance direction back into a starting position, from which a new work cycle starts. When the forming tool 1 closes, the rear - relative to the production direction - web 25 of the hold-down device 7 moves from the starting position of the forming tool 1 to the boundary of the strand section that was formed by the front web 25 in the previous work cycle.

Figure 9 shows a hold-down device 7 of the type described, in an axonometric representation. Shown clearly are the webs 22 extending parallel to the production strand, against which the insulating elements 21 on both sides bear.
The webs 22 are connected to one another via two webs 25, which extend transversely overall and penetrate the production strand when the hold-down device 7 closes. The webs 25 delimit the section of the production strand that can be deformed in one work cycle of the forming tool. The leads 26 for the heating element, which is not shown, and the associated sensors are disposed laterally on the hold-down device 7.

Figure 10 shows an axonometric representation of a base plate 5 having a mold plate 6 fastened thereon. The webs 14 that laterally delimit a mold segment 15 protrude from the mold plate 6. The insertable base 12 forms the -12- BD/Kr 10072 base of the mold segments. The selection of the mold segments 15, in the shape of cheese wedges in this case, defines the shape of the individual packages.

Figure 11 shows a production strand of the filled film strip 2 at various points in time of the forming process, which occur one after the other in the production strand. Cavities 23 are formed in the double-layer film strip 2, which is filled with food mass 16 and is sealed by way of two longitudinal sealing seams 19, said cavities being separated by a sealing area 24 into cavities 23 that are disposed one after the other and define the individual package 27 of the food mass. The sealing area 24 encircling each individual package 27 is sealed by way of ultrasonic sealing means, thereby removing any remaining food mass 16 from the sealing area 24 that has not yet been displaced by the webs 14. In a further method step, the consecutive individual packages 27 are separated from one another. In so doing, the film edge regions 20 are cut off in such a way that a remaining film edge region of the two film layers 17, 18 forms an opening tab 28 for the individual package 27.

Claims (10)

1. A method for the portioned packaging of an at least substantially incompressible food mass (16), more particularly of processed cheese, which is filled as a flowable mass into a tubular wrapping comprising a thermoplastic plastic film, characterized in that the thermoplastic plastic film of the wrapping (2) enclosing the food mass (16) is shaped in a mold into individual units (23), each defining a portion, by displacement of the food mass out of sealing areas, in that the units (23) disposed one behind the other are delimited with respect to each other in the sealing area (24) by way of sealing and are subsequently separated from one another.

2. The method according to claim 1, characterized in that a vacuum that suctions the plastic film into the mold is generated in a forming means (1) in order to support the shaping of a unit (23) in the film layer (17, 18).

3. The method according to claim 1 or 2, characterized in that the vacuum is generated after one segment (7) of the forming means (1) has been moved completely into the food mass (16) enclosed by the film strip (2).

4. The method according to one of the preceding claims, characterized in that the sealing is carried out using ultrasound, wherein parts of the forming means in particular are used as ultrasonic generators ("sonotrodes").

5. The method according to claim 4, characterized in that the portions are separated from one another by cuts in the sealing area.

6. The method according to one of the preceding claims, characterized in that the tubular wrapping is formed by a film strip (2) sealed on the longitudinal side, wherein adjacently disposed film edge regions (20) remain, which form the opening tabs (27) for the individual package (27).

7. A device for the portioned packaging of a flowable, at least substantially incompressible food mass (16), more particularly for carrying out the method according to one of the preceding claims, characterized by - filling means for filling a tubular wrapping comprising a thermoplastic plastic film with the flowable food mass (16), - forming means (1) for creating units (23), each defining a portion, from the wrapping (2), wherein the forming means (1) comprises mold segments (15) for forming consecutive units (23) having a specifiable shape in the film strip (2), - sealing means for creating sealing areas (24) delimiting the units (23), each forming a portion, - cutting means for separating portions.

8. The device according to claim 7, characterized in that the sealing means comprises a sonotrode for the ultrasonic sealing of the seating area (24).

9. The device according to claim 7 or 8, characterized in that the forming means (12) comprises means for generating a vacuum in the mold segments (15).

10. Packaging for an at least substantially incompressible food mass (16), more particularly for processed cheese, manufactured according to the method of claims 1 and 6.