MXPA99004374A - Process and device for molding congela store items - Google Patents

Abstract

The present invention describes the device for molding frozen confectionery articles, comprising a metering hopper connected to a volumetric dosing device comprising a metering chamber and a metering element that supplies a predetermined volume of ice cream to passing containers, by means of a nozzle dosing When the hopper is pressurized the dosing chamber is filled without the formation of air pockets in the suction phase, which makes it possible to manufacture molded articles of solid ice cream.

Description

PROCESS AND DEVICE FOR MOLDING FROZEN PASTRY ITEMS DESCRIPTION OF THE INVENTION The present invention relates to a process and a device for molding frozen confectionery articles, particularly small frozen bars. The small frozen confectionary bars are manufactured on an industrial scale by means of molding or extrusion. When the extrusion is used, the products are manufactured by cutting, in sections, a sausage shape of plastic consistency, which is rela tively hard at a temperature of the order of -6 ° C to -7 ° C, extruded vertically at the outlet of a freezer. The extrusion gives the product a fine texture, less crystallized than that of the molded products. The fine texture obtained by means of extrusion is largely due to the conditions of freezing in a freezer and, in particular, to the freezing temperature at the outlet of the freezer. That is, the lower the temperature, the less large crystals form. This means that the faster the freezing, the smaller the ice crystals and the finer the texture. In a freezer, the freezing speed is at its maximum thanks to the mixing and continuous scraping of the wall, which allows an accelerated freezing of the water. A disadvantage of this method is that the shape of the extruded products is limited. The freezing of a liquid composition to be frozen by means of molding through simple thermal conduction in a mold immersed in a cooling solution is slower and results in the formation of considerably larger crystals. In this process, the composition that is going to be frozen is always dosed in a liquid state in molds in order to guarantee a satisfactory filling and prevent the creation of air pockets, and its temperature is of the order of -2o C to -3o C. The proportion of frozen water is low, and most of the process of freezing the product takes place in the molds. This explains the presence of a thicker texture, more crystallized, due to an increase in the size of the crystals. US-A-3632245, for example, describes an apparatus for manufacturing short frozen bars in multiple channels by means of molding, in which rows of cells are simultaneously filled with a dosed amount of liquid composition to be frozen from distribution hoppers. associated with volumetric dosing devices that comprise cylinders that constitute dosing chambers, in which the liquid is successively sucked and then expelled by means of metering pistons. After this filling operation, the cells travel in a cooling liquid in such a way that the articles are frozen. As the composition that is going to be frozen is liquid, the simple pressure drop created by the displacement of the piston in its chamber allows the perfect filling of the cylinders. Thus, the identical filling of the cylinders allows the simultaneous dosing of an identical volume in the molds for all the channels. The object of the invention is to provide molded products, whose quality is similar to that previously obtained in the case only of extruded products. The invention thus relates to a process for molding frozen confectionery, in which containers passing through a solidification environment are filled with a predetermined volume of composition by means of a volumetric dosing device connected to a distribution hopper, the dosing device comprises a dosing chamber, which is filled with composition in the aspiration phase, and a dosing element, which expels the predetermined volume of composition of the chamber in the dosing phase, characterized in that a firm composition is dosed while keeping it low pressure upstream of the dosing element, and because the distribution hopper, which is kept under pressure, allows a continuous supply to the dosing chamber, to fill the molds without the formation of air pockets. In the context of the invention, a firm composition is an ice cream, which can be a frozen cream, an ice cream, a granita, which may or may not be aerated, and the term "ice cream" used below will refer to such compositions without distinction. A firm ice cream of this type is at -6o C, -7o C and, in practice, emerges from a freezer. Its texture is firmer than a conventional liquid composition that is going to be frozen, and it has a percentage of frozen water relative to the total water of the recipe of 50% or more, particularly 50 to 70%, depending on the composition of the mixture It's going to be frozen. An ice cream of this type can contain inclusions such as, for example, pieces of dried or candied fruit, pieces of jelly or fondant, crunchy pieces, compote, pieces of candy, or pieces of chocolate or sponge cake. The invention also relates to a device for molding frozen confectionery articles, filling containers passing through a solidification environment with a predetermined volume of composition, the device comprising: a distribution hopper containing the composition; means for dosing the composition, which are attached to the hopper, comprising a metering chamber, a dosing element, a dosing nozzle, and a valve that communicates either with the hopper and the dosing chamber during the aspiration phase, or with the dosing chamber and the dosing nozzle during the filling phase; characterized in that the hopper is sealed and is not deformable, and in that the device comprises means for maintaining a pressure on the composition during the suction phase, to fill the dosing chamber entirely. The device according to the invention can be applied to any machine for freezing frozen confectionery articles such as, for example: a machine for freezing in brine, which has rectilinear, rotary, oval or square movement; a freezing machine that uses a liquid, gaseous or evaporating cooling fluid, which coats the molds or roela for reasonably long periods; a machine in which the molds are transported by a conveyor in a pulsed air tunnel, to effect a rapid freezing, being possible for the conveyor to be rectilinear or rolled, for example, as a single or double helix, which is flattened or is of revolution; any machine of the type above in which the displacement of the molds is continuous or in successive increments. The device according to the invention can be applied in a very simple way to existing machines by converting the dosing devices to create an overpressure in the dosing hopper, for example, by closing it by means of a lid, making it gas-tight and connecting it to a source of fluid, particularly of compressed gas, for example of compressed air. This principle of dosing under pressure can be applied to various types of metering devices such as, for example, dosing devices with a supply envelope and with vertical or horizontal cylinders, metering devices with valves or dosing devices with submerged nozzles of the filling device type with the lower part upwards and the pencil-type filling device. The invention will be described in greater detail by way of illustration with the help of the appended drawings, in which: Figure 1 is a diagrammatic view of the device during the filling phase of the dosing chamber; Figure 2 is a diagrammatic view of the device of Figure 1 during the phase of filling a mold; Figure 3 is a diagrammatic view of a variant of the device just before filling a mold; Figure 4 is a partial diagrammatic view of the device of Figure 3 just before filling a mold; and Figure 5 is a partial diagrammatic view of a second variant of the device just after filling a mold.

In Figures 1 and 2, a tube 1, connected laterally to the hopper 2, feeds the latter with ice cream at -6 ° C, -7 ° C, which comes out of a freezer. A tube 3 transports compressed air to the hopper 2, to put it under a pressure of 1.53 - 2.04 kg / cm2 (1.5 - 2 bar). The pressure in the hopper is regulated by a valve 4 and controlled by a pressure gauge 5. The hopper 2 is closed by a cover 6, and the hopper / lid assembly is non-deformable and preferably gas-tight. The hopper / lid assembly can preferably be temperature controlled. In the lower part of the hopper 2, a tube 7 supplies the ice cream to the volumetric dosing device 8 comprising a hollow body or shell 9 in which a cylindrical valve 10, perforated with as many passages 11 as there are dosing channels (for reasons of clarity , only one channel is shown), allows communication either with the hopper 2 or with the dosing nozzle 12 by means of the interposition of the reinforced flexible hose 13, which rotates through a quarter of a revolution. The dosing device 8 comprises a metering chamber 14 and a metering piston 15. The rotating valve 10 can be replaced by a set of double-slide valves, which fulfill the same function but make the dosing device more bulky. A mixer 16 pressurizes the tube 7 communicating with the casing 9. The nozzle 12 is secured to an ascending and descending support (not shown), which allows it to descend into the mold 17 and to rise out of the mold 17. The molds 17 they are cooled before and / or after they have been filled by means of a cooling vector. The molding can be applied to any mold in one or several parts in contact with any liquid, gaseous or solid cooling environment such as, for example, brine, a solution of glycol water, pulsatile air, liquid nitrogen or solid carbon dioxide. The nozzle 12 can also be secured under a valve (not shown) which, closing just after dosing, prevents it from being dosed too much of the ice cream, or prevents it from dripping due to the residual volume contained in the flexible hose 13. In the Figure 1, in a production situation, an empty mold 17, which gradually passes over a conveying line 18 in the direction of the arrow fl is presented under the nozzle 12. The latter is lowered to the lower part of the mold 17 according to f2, while the cylinder 14 constituting the metering chamber is filled with composition pushed from the hopper 2 by the compressed air via the tube 7, then the passage 11 of the valve 10, and the piston rises again according to f3. As indicated in Figure 2, the valve 10 rotates through a quarter of a revolution, which places the cylinder 14 in communication with the tube 13 by means of the interposition of the passage 11. The piston 15 descends according to f4, and the precise volume of ice cream contained in the cylinder 14 fills the mold 17 by means of the nozzle 12, which rises progressively according to f5, upon filling. In Figures 3 and 4, the dosing principle is the same as that described above, except that the nozzle 19 slides in a delivery device 20, which is integral with the casing 9. In Figure 3, the cylinder 14 it has been filled with ice cream, and this is dosed by the descent of the piston 15 according to f6 via the channel 11 and the window 21 made in the body of the delivery device 20, the communication with the window 22 of the nozzle 19 is presented in the lower part of the mold 17. The nozzle 19 is driven by a pressure cylinder (not shown), which raises it progressively according to f7 during filling.

After the mold has been filled, as shown in Figure 4, the valve 10 rotates through one revolution, which puts the cylinder 14 in communication with the tube 7 connected to the hopper by means of the interposition of the passage 11. The piston 15 is then in a position in which it is ready to aspirate, and it rises according to f8. In this case, the dead volumes are minimized, and the valve 10 is synchronized with the lowering and raising of the nozzle, using an automatic program. According to an operational variant, an arrangement can be made so that the nozzle remains stationary and so that the mold is taken by an ascending and descending device, that is, it is raised at the beginning of filling and then progressively lowered during filling. In the variant of Figure 5, the dosing device is provided with a static nozzle 23 placed directly below the casing 9 in direct connection with the cylinder 14. The three-way rotary valve 24 allows communication between the tube 7 connected to the hopper, the cylinder 14 and the nozzle 23. During filling, the piston 15 descends according to f9 and doses the ice cream inside the mold 17. The nozzle 23 has a narrow opening 25, for example <; 4 mm in diameter, which allows the ice cream to be made sufficiently fluid by means of shear, and the mold to be filled satisfactorily. In this variant, there is no longer a need for an ascending and descending nozzle holder and therefore the overall size is minimized. In a modality that is particularly adapted to a multi-channel manufacturing line, not shown for reasons of simplification, the hopper, such as 2, which is common to all channels, has a generally cylindrical shape, is arranged horizontally, transverse to the channels, it has two ice cream supply tubes, such as 1, arranged on each side of the cylinder and exit tubes for the ice cream, such as 7, arranged opposite each channel. An agitator / distributor, such as 16, comprises a rotary shaft located on the axis of the cylinder, and blades secured transversely to the axis of the agitator, on either side of the shaft, in a position in which they are alternated with respect to each other. The blades are arranged in a decentralized manner relative to the exit tubes for the ice cream, opposite spaces located on either side of the outlet tubes. The blades preferably have a length such that their end is in the vicinity of the inner wall of the cylinder, a helical shape and an orientation with an angle which, closer to the central part of the cylinder, is increasingly less pronounced, making It is possible for the flow of ice cream that originates from the supply tubes that is directed preferentially towards the central part of the cylinder, to decentralize the preferential flow towards the ends. In this way, the ice cream is distributed homogeneously between the various outlet tubes and is capable of pressurizing the dosing chambers without the creation of an air pocket. During operation, the agitator / distributor is driven in slow rotation by means of a motor outside the hopper, which engages on the agitator shaft, for example a pneumatic motor, and the seal can be provided, for example, by a flange seal on the motor side and a packing box on the other side of the cylinder. The hopper is fed continuously. If the level of ice cream rises in the hopper, the air pressure increases in its upper part. This increase in pressure, compared to a reference value, can generate a signal acting on the closing of a valve, such as 1, or on the reduction of the speed of the pump that supplies product from the freezer, to reduce its speed. flow. A main advantage of the cylindrical hopper above is that, due to its geometry, it can be cleaned by chemical agents and, if appropriate, sterilized, for example using hot water or steam, while remaining in situ without being dismantled. The advantages provided by the process and the device over the traditional molding media are many: it is possible to dose the ice cream containing much more water in a frozen state than in the past, with a corresponding improvement in the texture, which is that which is usually found only in extruded articles, regardless of the fat content; the freezing time can be reduced by 30 to 50%, which allows a higher production speed and an improved productivity for the line; the viscosity of the ice cream is such that the inclusions it contains, if appropriate, can be uniformly distributed without being sedimented as in the case of a liquid dosed ice cream; it is possible to manufacture composite articles by dosing the ice cream by means of a coating nozzle, to form a cover that remains in place on the mold wall, and then it is possible to fill the center to form a frozen confectionery core of a different type, producing a contrast in texture and / or taste; It is possible to manufacture "three-dimensional" or "non-demouldable" items using multi-part molds; the articles, being colder, can be coated more easily, for example with a coating having a fat composition, with a granita, with a sorbet or with an emulsion. The device and the process have been described in relation to the manufacture of frozen pallets. They can, of course, be used to manufacture other molded articles such as, for example, cones or tubes. The device has been described with reference to the drawings in relation to a dosing channel for reasons of simplification. Naturally, a machine in a manufacturing situation can comprise up to 20 parallel dosing channels.

Claims (11)

1. RE IVINDICATIONS 1. Process for molding frozen confectionery, in which the containers passing through a solidification environment are filled with a predetermined volume of composition by means of a volumetric dosing device connected to a distribution hopper, the dosing device comprises a dosing chamber, which is filled with composition in the aspiration phase, and a dosing element, which expels the predetermined volume of composition of the chamber in the dosing phase, characterized in that a firm composition is dosed while kept under upstream pressure of the dosing element, and because the distribution hopper, which is kept under pressure, allows a continuous supply to the dosing chamber, to fill the molds without the formation of air pockets.
2. 2. Process according to claim 1, characterized in that the firm composition is an ice cream at -6 ° C, -7 ° C, with a texture that is firmer than a conventional liquid composition that is going to be frozen, and because it has a percentage of water frozen relative to the total water of the recipe that is 50% or more, particularly 50 to 70%, depending on the composition of the mixture to be frozen.
3. 3. Process according to claim 1 or 2, characterized in that the ice cream contains inclusions, particularly pieces of dried or candied fruit, pieces of jelly or fondant, crispy pieces, compote, pieces of candy, or pieces of chocolate or sponge cake.
4. 4. Process according to claim 1, characterized in that the ice cream is introduced into the metering chamber under pressure of a gas, particularly an air pressure, of 1.53 to 2.04 kg / cm2 (1.5 to 2 bars)
5. 5. Device for molding frozen confectionery articles filling containers passing through a solidification environment with a predetermined volume of composition, the device comprising: a distribution hopper containing the composition; means for dosing the composition, which are attached to the hopper, comprising a metering chamber, a dosing element, a dosing nozzle, and a valve that communicates either with the hopper and the metering chamber during the aspiration phase, or with the dosing chamber and the dosing nozzle during the filling phase; characterized in that the hopper is sealed and is not deformable, and in that the device comprises means for maintaining a pressure on the composition during the suction phase, to fill the dosing chamber entirely.
6. 6. Device according to claim 5, characterized in that the hopper is sealed by a lid, and because the hopper / lid assembly is non-deformable, gas tight and temperature controlled.
7. 7. Device according to claim 5, characterized in that the dosing nozzle is connected to the valve by means of a flexible hose, and because this is integral with an ascending and descending support, in such a way that it descends inside the container at the beginning of the filling , it rises during filling and re-emerges from the container at the end of filling.
8. 8. Device according to claim 5, characterized in that the valve turns or rotates in a casing, and in that the dosing nozzle slides in a delivery device, which is integral with the casing, in such a way that it descends inside the container in the start of filling, rises during filling and re-emerges from the container at the end of filling.
9. 9. Device according to claim 5, characterized in that the valve turns or rotates in the casing, because the dosing nozzle is integral with the casing, because this is in direct connection with the dosing chamber, and because the nozzle opening is sufficiently narrow to allow the ice cream to be fluidized by shear.
10. 10. Device according to claim 5, adapted for dosing the ice cream in parallel along several channels, characterized in that the hopper is generally cylindrical in shape, because it is non-deformable, gas-tight, and temperature-controlled, and because it comprises means for the homogeneous pressure feeding of the dosing chambers with the ice cream without the formation of air pockets, particularly an agitator / distributor with oriented vanes.
11. 11. Molded frozen pallet, capable of being obtained by means of the process according to any of claims 1 to 4, characterized in that its texture is the same as that of a frozen pallet extruded at approximately -6 ° C, -7 ° C.