Method for preparing a beverage from a capsule and device therefor

The present invention relates to a method for preparing a beverage or food liquid from a cartridge, such a cartridge containing an extractable substance, and a device for preparing a beverage by this method.

A method for preparing a beverage from a cartridge containing an extraction product, e.g. coffee, is known from international patent application WO9207775. The cartridge is placed in a special base that can be hermetically pressed onto the injection head to obtain hot water injection into the cartridge. This base from below is provided with a perforating means for the bottom of the cartridge to allow coffee or other beverage to be extracted from the cartridge.

In known devices, various systems are used to inject water into the cartridge. Some systems include a mesh provided with a plurality of holes for distributing the injected water through the upper porous membrane of the cartridge, such as the systems described in European patent application EP 0 006 175. Injection heads may also be provided with a plurality of needles for piercing the membrane

Z-4646

EP 1 646 304 B1 closing the cartridge, such as those described in US Patent No. 3,607,297. In some systems, the head is equipped with one or more injection needles, each of which is equipped with a water injection channel and, perforating the upper membrane of the cartridge, through the injection channels located in the injection needles injects water directly into the cartridge. Injection heads fitted with perforating means allow the cartridge to be fitted with an upper closing membrane that does not need to be removed before use.

The disadvantage of single needle injection systems in which the water injection hole is located in the center of the cartridge is that they do not distribute the injected water through the product contained inside the cartridge in a uniform manner, and this contributes to the formation of selective flow channels in the extraction substance. The result is incomplete extraction of the extracted product, and a large pressure drop inside the cartridge during extraction, due to the low resistance exhibited by the selective flow channels.

Compared to injection systems using single needles, systems having multiple perforating needle heads described in US 3 327 614, EP 604 615 or EP 1 203 554 have less problems with the formation of selective flow channels, which, however, cannot be completely eliminated.

EP 0 521 187 describes an arrangement with an injection head comprising a grid for distributing the introduced water, having on the lower surface protruding elements designed to allow the upper wall of the cartridge to tear.

Z-4646

EP 1 646 304 B1

In all known systems, the resistance of flowing water introduced under water pressure to the product contained in the cartridge tends to decrease during extraction, especially in its last phase.

In view of the disadvantages of the known systems mentioned above, the object of the invention is to provide an efficient method for preparing a drink or other food liquid using an extraction cartridge that would allow the extraction of said substance to be improved.

Another object of the invention is to provide a device and cartridge containing an extraction product for the preparation of a drink or other food liquid that would allow the extraction of said substance to be improved.

An advantageous feature of the invention is to provide a method for preparing a drink or other food liquid and a device with a cartridge for preparing a drink in such a way that would allow the taste and consistency of the obtained drink or other food liquid to be improved.

An advantageous feature of the invention is to provide a method and device with a cartridge for preparing a drink by this method, especially for the preparation of hot coffee or chocolate that would allow a thick foam to form.

The invention may be carried out by a process for preparing a drink or other food liquid according to claim 1 and using a device for preparing a drink or other food liquid according to claim 1. 8.

In a preferred embodiment of the invention, the method, device and cartridge of the invention allow for good distribution introduced under

Z-4646

The pressure of the water into the cartridge and maintaining a constant counter pressure inside the cartridge to improve the extraction of the product for extraction within the cartridge.

Furthermore, the method, device and cartridge of the invention prevent the formation of selective flow channels. For a product such as ground coffee, which leaves traces of residue in the cartridge, the pressure exerted on the extraction product through the upper membrane of the cartridge allows, on the one hand, to avoid the formation of selective flow channels and, on the other hand, to maintain a pressure opposite to the injection pressure to ensure high extraction pressure throughout the entire extraction cycle, which improves extraction and allows you to achieve a richer taste and better use of the entire product contained in the cartridge.

In addition, the high pressure used throughout the entire extraction cycle allows for very good foam.

Foam recovery can be improved by providing at the bottom of the receiver base 15 with a wall comprising an upwardly projecting opening provided with partial drainage outlets for removing the extracted fluid, with a portion of foam flowing through the upwardly projecting opening of the collecting portion.

For products such as chocolate or milk powder that do not leave trace residues in the cartridge and which are completely extracted, the method, device and cartridge according to the invention allow complete extraction and the formation of a good foam.

Other preferred objects and features of the invention follow from the claims, the description and the attached drawing. The attached drawing contains the following figures:

Z-4646

EP 1 646 304 B1

Fig. 1. A cross-section through a part of the device for preparing a drink or other food liquid, showing a part of the injection head and cartridge base in which the cartridge filled with the substance to be extracted is located; the injection head and cartridge base are shown in the initial position, awaiting extraction;

Fig. 2. View as in Fig. 1, however with the injection head from above in the "ready for injection" position, ie pressed tightly against the upper wall of the cartridge and the base in which the cartridge was placed;

Fig. 2a. Detailed view showing perforation through a sharp perforating needle from an injection head in a flexible cartridge membrane;

Fig. 3. View as in Fig. 2, in a first water injection stage;

Fig. 4. View as in Fig. 3, in a more advanced stage of water injection;

Fig. 5. Cross-section through an alternative injection head variant and cartridge; and

Fig. 6. Cross-section through yet another variant of the injection head and the cartridge according to the invention.

With reference to the drawing, the device for preparing a drink or food liquid from the cartridge 1 containing the product 2 with the substance to be extracted contains an injection head 3 and a base for placing the cartridge 4 which can be tightly pressed against the injection head as illustrated in figures 2 to 4 using a bayonet or other system. The base for placing the cartridge 4 has a side wall 5 and a central bottom wall, forming together the upper part of the tank 7a in which the cartridge 1 is located. The side wall 5 has a slightly conical shape which corresponds to the conical shape of the side wall of the cartridge 8. In a preferred embodiment of the invention, the middle bottom wall 6 may also be provided with a form

Z-4646

The filter wall is equipped with a plurality of perforating needles 9 and drainage holes 10 passing through the side wall, the needles being designed to perforate the bottom wall of the cartridge.

In a preferred embodiment of the invention, the bottom wall of the cartridge 11 may have an arcuate shape (seen from the outside) which bulges outwards when a certain pressure is reached in the cartridge during the water injection, thus enabling the needles perforating 9 perforating the bottom wall 11 and flowing out of the extracted beverage through the drainage holes 10 of the filtering wall 6. Fluid flows into the lower part of the tank 7b in the base for placing the cartridge, which tank is located between the middle bottom wall 6 and the bottom wall 12.

The bottom wall 12 of the cartridge holder 4 has a drainage channel 13, which is surrounded by an edge projecting upwards from the lowest point 15 of the bottom wall 12, which edge requires one or more outlets 16 going to the lowest point 15 of the bottom part of the tank 7b , to allow complete evacuation of the fluid from the base. The upwardly protruding edge 14 allows a portion of foam 27 floating on the surface of the fluid 28 in the bottom cavity to flow into the drainage channel 13 at the same time as the fluid without foam through the upward opening. This arrangement allows the foam to be recovered more than in a conventional system in which the drainage channel has a hole located flat at the lowest point.

Cartridge 1 requires a flexible membrane 17 integrated or connected to a portion of the annular flange 18, radiating from one end 19 of the side wall 8 of the cartridge 1. Both the collar portion 18 and the integrated portion of the flexible membrane 17 are held between the annular

Z-4646

With the seal 20 on the injection head and the upper portion of the base flange 21 4. In a preferred embodiment of the invention, the side wall 8 and bottom wall 11 of the cartridge form a single injection mold made of a polymer such as polypropylene or other plastic material for recovery. The side wall 8 and bottom wall 11 form a thin package that is relatively rigid compared to the flexible membrane 17. In a preferred embodiment of the invention, the flexible membrane 17 consists of one or more polymers selected for their plastic properties and susceptibility to significant permanent and / or reversible deformation. In a preferred embodiment of the invention, the flexible membrane comprises material similar to or identical to the walls 8 and 11, which facilitates the recovery (recycling) of materials from the used cartridge.

In a preferred embodiment of the invention, the flexible membrane 17 may be made of a multilayer sheet, such as a multilayer polypropylene sheet, to increase the tensile strength and deformability (reversible and / or solid). This is important in view of the fact that the membrane, subjected to high pressure of water introduced during extraction, deforms significantly. In a preferred embodiment of the invention, the multilayer membrane may be made of more than five layers. It has been revealed that seven layers achieve flexibility and tensile strength; which is necessary for specific applications.

During extraction, part of the annular collar 18 acts as a support able to withstand the tensile force exerted by the membrane, not only because part of the collar exhibits radial resistance but also because the annular collar

Z-4646

EP 1 646 304 B1 is pressed and held in a grip between the base for placing the cartridge and the annular gasket 20 on the injection head.

The injection head 3 comprises a body 22 having a water injection channel 23 opening to a perforated surface 24 provided with a plurality of perforating needles 25 spaced apart on the perforated surface 24. In this embodiment, the water injection channel opens substantially in the center of the perforated surface 24 , but there may be several injection channels that open at different locations on the perforated surface. The diameter of the perforated surface 24 is approximately equal to or smaller than the diameter of the plastic membrane 17 of the cartridge.

In a preferred embodiment of the invention, the perforation needles 25 have an arcuate shape, i.e. a circular cross-section. The perforation needles may also have an elliptical cross-section or any other round shape (i.e. without any sharp edges), being a cone ended with a perforating needle. In a preferred embodiment of the invention, the side line of the perforating needle 29 is a straight line, but may also be a curved line.

In a preferred embodiment of the invention, the surface of the perforating needles without sharp edges makes it possible to obtain an aperture 26 formed in the flexible membrane 17 having an edge 26 (Fig. 2a) smooth, uniform, and free of pointed fragments, in order to avoid breaking of the membrane under the applied voltage force.

In a preferred embodiment of the invention, the cone angle of the perforating needles is between 30 and 50^about. The diameter of the perforation 26 is determined by the angle of the cone i

Z-4646

The depth of penetration of the blade into the membrane 17. The depth of penetration of the perforating needles through the membrane 17 depends, in particular, on the resistance exhibited by the product 2 inside the cartridge when the injection head is in the lowered position "ready for injection" as shown in Fig. 2.

The properties of the reversible and permanent deformation of the membrane 17, in combination with the shape of the perforating needles (having a smooth surface and a cone with a certain angle), allows the formation of holes 26 in the shape of the membrane that makes the membrane tear-resistant, and whose larger or smaller size depends on the amount and packing the cartridge-filling product.

The smaller the filling of the cartridge with product 2, the smaller the perforation holes of the membrane will be. In a situation where the product does not exert any opposite resistance during perforation, the diameter of the holes 26 depends on the shape of the perforating surface 24, the elastic and plastic properties of the flexible membrane 17 and the shape of the perforating needles.

When the water is pressurized by the injection channels 23, the flexible membrane is deformed under pressure, as shown in Fig. 3, and moves away from the perforating surface 24 of the injection head. Water under pressure flows through the flexible membrane through the plurality of perforation holes 26 distributed over the surface of the membrane and moistens the product contained in the cartridge. The increase in pressure in the cartridge causes the bottom wall 11 to bulge outwardly and this wall is consequently rapidly exposed to the perforating needles of the filtering wall 6 and perforates, so the fluid 28 flows into the lower part of the tank 7b, as shown in Fig. 4.

Z-4646

EP 1 646 304 B1

The pressure exerted on the product inside the cartridge by the flexible membrane during extraction means that the product remains relatively densely packed and prevents the formation of selective flow channels. On the other hand, the pressure exerted by the membrane makes it possible to provide a high resistance against fluid flow through the product throughout the entire extraction cycle, thus improving product wetting, extraction and foam formation. The deformation measure of the flexible membrane 17 is determined by the variable hydraulic pressure ΡΡ between the surface 17a on which water falls and the surface 17b facing the inside of the cartridge. Variable pressure ΔP depends on the size and number of 10 holes 26. The size of these holes 26 is a function of, among others, the resistance exerted by the membrane 17 during perforation with the needles 25. This resistance depends, in particular, on the quantity of product 2 contained in the cartridge 8 . In this case, automatic packing adjustment of the product 2 contained in the cartridge 8 is ensured. The less product in the cartridge, the greater the deformation of the membrane and the weaker the water flow, which also reduces the formation of selective flow channels.

The shape of the perforating surface 24 is convex, as shown in Fig. 6, to fit the flexible membrane 17 of the cartridge, which is essentially flat. The curvature of the perforating surface 24, 24 ', 24 "may be more or less marked and, in the case of the perforating surface 24" having a strong curvature, the flexible membrane may even be concave (viewed from the outside) as indicated by No. 17'. Injection heads with 24 ”perforating surfaces with a strong curvature can be very useful when the cartridge 1 is filled with a small amount of product, as can be the case with tea.

Z-4646

EP 1 646 304 B1

The invention also includes an injection head with a perforating surface having a concave shape (viewed from the outside) 24 "" when the cartridges are completely filled and the flexible membrane 17 "" has a convex shape (viewed from the outside). In this case, the flexible 17 '' membrane itself can even be semi-rigid and thermoformed, due to the fact that it is not subjected to voltage deformation in the initial phase of extraction or does not show any stiffness if the packed product in the battle has a volume greater than the specified volume through the cartridge packaging and the membrane in the "concave" position (symmetrically in relation to the "convex" position)

Monodor SA, Switzerland Representative

Sławomir Łazewska

Z-4646

EP 1 646 304 B1