Rigid cartridge for coffee and soluble products for preparing beverages

A cartridge (1) for coffee or soluble products for producing a beverage, includes a container (2) able to contain the coffee or soluble product, a lid (6) disposed over the container so as to define a top wall for entry into the container of the hot water under pressure for formation of the beverage, a filter (4) able to be positioned inside the container above a bottom wall (20) of the container through which the beverage flows out, wherein the bottom wall of the container has a weakened, less thick central area (22), suitable to be broken by mechanical elements or by the pressure of the liquid inside the cartridge to allow delivery of the beverage, there being provided a plurality of concentric, spiral-shaped channels, ending in the less thick central area, able to cause a swirling movement of the beverage, with the consequent formation of a dense froth.

The present invention refers to a cartridge or capsule for containing coffee or soluble products in general, such as for example barley, powdered milk, tea, chamomile, herb teas and the like, for preparing the respective beverages.

In the rest of this description, it being understood that the cartridge according to the invention can be used for the preparation of the various beverages mentioned above, specific reference will be made to coffee, the product for which the cartridge according to the invention has been particularly designed.

Essentially two types of cartridge for containing coffee in powder or fine granules are widely available on the market: rigid cartridges and flexible cartridges.

The cartridge according to the invention is of the rigid type, so reference will be made hereunder only to this type of cartridge of the prior art.

Rigid cartridges are substantially cylindrical in shape, comprise two half-shells of rigid plastic material, heat-sealed or hot-glued together, and enclose on their inside the coffee in powder placed on a filter in contact with the bottom wall of the cartridge.

Normally the bottom wall of the cartridge is perforated, whilst the upper wall may or may not be perforated, depending upon the type of apparatus used for extraction of the beverage, that is, whether it is with perforation of the upper wall or with simple injection of hot water under pressure, which, by passing through the powder product, enters the cartridge and captures its aromas, passes through the filter which retains the powder product, and flows out through the holes provided in the bottom wall, thus producing the beverage which is caught in an appropriate glass or cup beneath.

This type of rigid cartridge with a perforated bottom wall on the one hand holds the drawback that the product inside it is exposed to the outside environment and can thus lose its fragrance if it is not tightly closed in a further protective package, and on the other hand that during infusion it is not possible to reach adequate water pressures, which has repercussions on the quality of the beverage obtained.

There also exist cartridges with a solid bottom wall, which is pierced by the point of the beverage extraction apparatus during delivery of the beverage.

Such a cartridge is described, for example, in patent EP 1364605, the content of which is incorporated herein by reference.

Such a cartridge makes it possible to obtain adequate pressurization before its bottom is perforated, and thus to overcome at least in part the drawbacks reported above.

Similar results are obtained with the cartridge described in EP 1555218, in the name of the same applicant, I.TA.CA S.r.L., the bottom wall of which is completely closed and has a weakened central portion with etchings arranged in cross, able to open when a pre-set pressure is reached, allowing the beverage to flow out.

However, the applicant, having noted that the beverage thus obtained with said cartridges is poorly emulsified, has carried out numerous studies aimed at improving the quality thereof.

Object of the invention is precisely to provide such a cartridge for coffee that makes it possible to obtain a beverage that is more emulsified and therefore more creamy, improving its quality compared with those obtainable up to now.

Another object of the invention is to provide such a cartridge for coffee that is simple and cheap to make and that can be used in various types of traditional beverage dispensing machines.

These objects are achieved according to the invention with the coffee cartridge having the characteristics of appended independent claim1.

Advantageous embodiments of the invention are apparent from the dependent claims.

Essentially, the cartridge of the rigid type according to the invention has on the bottom wall a plurality of concentric spiral-shaped channels which go from the peripheral edge of the bottom wall to a weakened, less thick central part.

The weakened central part may advantageously be doughnut-shaped or annular and is perforated with mechanical means during the beverage extraction step, or alternatively it may have etchings which open causing said weakened wall to be knocked out when an adequate water pressure is reached inside the container.

The provision of such spiral-shaped channels on the bottom of the cartridge produces a swirling movement of the liquid during delivery, allowing a creamy beverage to be obtained, with the cream persisting on the beverage for several minutes.

Coffee is in fact a food rich in essential oils and at the time of delivery of the beverage it creates an emulsion, namely the cream of the coffee. Experimental tests carried out by the applicant have demonstrated that the cream that can be obtained with the cartridge according to the invention is qualitatively superior to that which can be obtained with cartridges of the prior art, whose bottom wall is normally flat or has radially disposed ribs.

With reference to said figures, the coffee cartridge according to the invention has been indicated as a whole with reference numeral1.

It comprises a container body2, frustoconical in shape (but it is obvious that it can also be cylindrical in shape), open at the top and comprising a bottom or lower wall20, essentially discoid in shape, from which a side wall21is erected with a slight upward taper.

The container2has on its bottom wall20a filter4, which will be better described further on, and is closed with a lid6after having been filled with coffee100(FIG. 2).

The bottom wall20has a circular-shaped central portion22, annular in shape in the embodiment illustrated, which is less thick than the remaining part of said bottom wall.

Said less thick, weakened central part22of the bottom wall20is suitable to be broken for delivery of the beverage, by means of an external mechanical member or by the pressure of the water inside the cartridge, as will be better described further on.

In order to facilitate breaking of said weakened, less thick part22, especially in the case of this taking place through an increase in the pressure inside the cartridge, cuts or etchings (not shown) that facilitate breakage can be provided thereon.

As can be seen better inFIG. 3on the bottom wall20there is provided a plurality of concentric spiral-shaped grooves24(four in the embodiment shown), which start from an annular peripheral edge23of the bottom wall, adjacent the side wall21, and end at said central weakened portion22.

In particular, as can be seen inFIG. 3, each spiral24has a very tapered initial portion25, at said peripheral edge23, which starts with a thickness of practically zero, and an enlarged terminal portion26(length), which ends in said weakened central part22of the bottom wall20.

The shape of the bottom22of the cartridge is such that between said grooved spirals24an equal number of raised spirals27are defined, which together with said peripheral edge23, form a base on which the filter4rests (see in particularFIG. 2).

Inside the side wall21of the container body2there is provided a plurality of thickening ribs29(four in the embodiment shown) perpendicular to the bottom wall20and reaching to about half the height of the container2.

The purpose of said thickenings29is to allow the containers to be stacked one on top of the other without them restraining each other, causing the bottom20of a container to abut against the free top ends of said thickening ribs29.

On the inner surface of the side wall21, near the bottom20of the container2there is also provided an annular projection or collar28, acting as a stop for positioning of the filter4.

The side wall21of the container also has an annular upper edge30protruding outwards so as to form a substantially flat upper surface31.

The container is made in a single body, by injection moulding of rigid plastic material such as plastics for food use and in particular polypropylene or other plastic materials. The bottom wall20and the side wall21of the container2do not have any perforation and have thicknesses designed to ensure that the container2has a certain stiffness so as to be able to withstand high pressures for a relatively long time.

The filter4is substantially discoidal in shape and has on its peripheral edge a collar48, able to be positioned beneath the collar28formed on the inner surface of the side wall21of the container, when the filter is disposed therein, resting on the raised spirals27and on the peripheral edge23of the bottom wall20, so that the filter4does not obstruct the central portion22of the bottom wall of the container and the beverage can circulate freely in the grooved spirals24during delivery.

The filter4thus positioned, as shown inFIG. 2, is preferably heat bonded to the side wall2of the container, at said collars48,28.

The filter4has on its discoid surface a plurality of conical or truncated pyramid shaped holes44, suitable for allowing the passage of the beverage from top to bottom and retaining the granular or powdery product above the filter inside the cartridge1.

When the filter4has been positioned on the bottom wall20of the container2, this is filled with coffee100or another soluble product and the container is closed with the lid6, which is fixed to the upper surface31of the annular rim30by means of heat bonding, ultrasonic bonding, gluing or the like.

The lid6can have micro perforations suitable to allow the passage of water and/or steam under pressure. For this purpose the lid6may be made from one or more layers of filter paper or one or more strips of micro perforated plastic material.

Alternatively, the lid6may have a completely airtight closure, and may optionally be made of rigid plastic material, if the beverage extraction apparatus provides means of perforating said lid.

For delivery of the beverage, the cartridge1according to the invention is disposed in a special per se known extracting apparatus such as the one described in the above mentioned patent EP 1364605, if mechanical knocking out of the weakened portion22of the bottom20of the container is provided, or as described in EP1555218, if knocking out of said weakened portion is to take place through an increase in the water pressure inside the cartridge.

After the cartridge has been positioned in said apparatus, hot water under pressure is introduced through the lid6into the cartridge1, coming into contact with the coffee100.

When the pressure of the water inside the cartridge reaches a pre-set level, knocking out of the weakened central portion22of the bottom20of the container takes place, as described above, giving rise to outlet apertures for the beverage, which flows in a special conduit of the apparatus and is collected in a glass or cup beneath.

Before reaching the above mentioned outlet apertures, the beverage is subjected to a swirling movement in said spiral channels24, which produces a highly emulsifying effect on the beverage flowing out, with the formation of an dense, long-lasting cream.

The applicant has been able to verify that such a result cannot be achieved with the cartridges previously used.

Naturally, the invention is not limited to the particular embodiment previously described and illustrated in the appended drawings, but it is possible to make thereto numerous modifications of detail within the reach of a person skilled in the art, without thereby departing from the scope of the invention as set forth in the appended claims.