GB2523775A

GB2523775A - Coffee capsule

Info

Publication number: GB2523775A
Application number: GB1403825.1A
Authority: GB
Inventors: Leslie Gort-Barten; Alex Gort-Barten
Original assignee: Individual
Current assignee: Individual
Priority date: 2014-03-04
Filing date: 2014-03-04
Publication date: 2015-09-09
Anticipated expiration: 2034-03-04
Also published as: GB2523775B; GB201403825D0

Abstract

A frusto conical capsule 1 having an annular flange 4 at one end, with a removable seal 5 which is plastically deformable on the side of the flange nearest the other end. Ideally the seal is provided with a code to be read by the coffee machine such as a bar code 6. The seal 5 can be received in a channel defined by an undercut provided on the flange and/or retained by pips. The sealing annulus can be expanded foam or foil.

Description

Coffee Capsule The invention relates to a capsule for making beverages such as espresso coffee or tea using an espresso machine.

Powered espresso machines are well known. The conventional espresso machine comprises a water chamber, a heating element adapted to heat the water to around 95- 98 C, which is then pumped under high pressure of 15 to t9 bar to a filter holder or portafilter. Lower pressure systems also exist. The filter holder typically comprises a handle portion and a holder portion provided with two or three lugs that are adapted to engage in the installed position with the machine brewhead to where the water is pumped. The holder portion is adapted to receive a filter, which is usually a metal bowl with a number of perforations through its bottom. In use, the filter is filled with finely ground coffee and the water is forced through the coffee at the high pressure generated by the pump to produce the espresso coffee which is collected in a cup placed under the filter holder.

The classic coffee machine suffers from two potential drawbacks. The first drawback is that ground coffee starts to lose its freshness and flavour after a few days and so for the optimum espresso, the user ll also need to have a coffee grinderS The other drawback is that the used espresso coffee has to be removed from the filter, which can lead to mess as the grinds are fine.

This lead to the development of ESE coffee pods, which can be used in many espresso machines. Coffee pods are generally individually wrapped to maintain freshness and consist of a small pod made of a perforated filter paper which contains the coffee. The pod is placed in the filter holder and then disposed of after use.

Coffee pods are convenient but have to fit the filter holder and be placed correctly otherwise water can leak around the edge.

This in turn lead to the development of capsule machines. The coffee capsules for these machines are completely sealed. The capsule machines do not use the conventional filter holder. A capsule machine typically has a two part mechanism.

The first part receives the capsule and is provided with an extraction surface upon which the capsule rests. The second part is provided with a locking lever which is used to make the first and second parts integral. In use, the second part cuts the upper surface of the capsule to allow water to enter the capsule and percolate down through the capsule, where it exits through the lower surface of the capsu'e at multiple locations determined by the geometry of the extraction surface. An example of such a machine is disclosed in EP 0870457 or W02005/004683. Capsules in the known capsule coffee machines are, in use, inserted into a capsule cage of the machine which holds the capsule in position so that it may be cut by a cutting member.

Capsule machines have proved to be commercially very successful as they are very convenient to use and produce a consistent product. However, each manufacturers coffee machines and capsules are designed to work with the manufacturers own brand, The most popular brand of capsule is Nespresso ®, which uses a sealed capsule. In use, the capsule is damped into position in the machine with a capsule cage part holding the capsule so that it can be cut by three prongs to enable water under pressure to enter the coffee capsule. The main alternative to this type of capsule is perforated with 6 to 9 holes to enable the water to enter the capsule. The perforations have one significant design drawback in that air can enter the capsule.

Consequently, the capsules are packaged in small quantities in nitrogen filled bags to enable the shelf life of the coffee to match that of a sealed capsule, This results in significantly increased transport and packaging costs.

A particular problem with capsule systems is ensuring a tight fit between the capsule cage and the capsule rim in the extraction position. Early solutions relied on simple mechanical pressure but more recent capsules, such as those sold under the Nespresso brand, have used a silicone paint applied to the underside of the rim. In use the capsule cage is applied to the seal to ensure that there is no loss of pressure. This seal has been effective but adds considerably to the production costs of the capsule.

It has been further proposed to use a series of deformable concentric rings formed on the rim, which in use are engaged by the capsule cage and deflected to ensure a pressure tight seal. However, the concentric rings need to be closely spaced and if a plastic capsule is used, then in production the capsule often sticks to mould.

Removing the capsule then results in wear to the tool. The known concentric ring solutions have a tendency to leak in certain coffee machines, in particular in machines designed specifically for use with certain capsules having a rubber elastic seal.

The present invention seeks to provide a coffee capsule with an improved seal.

According to the invention there is provided a capsule for use in a coffee machine having a generally frusto-conical form with an upper surface and a lower surface, an annular flange being provided at the lower surface, which annular flange is provided with sealing means on the surface facing towards the upper surface, wherein the sealing means comprises a detatchable annular element adapted to be plastically deformed when engaged by a capsule cage to thereby provide a seal between the capsule flange and the capsule cage, the annular element being retained in position by retaining means.

Preferably, the retaining means comprises one or more retaining pips on the external capsule wall or on the free edge of the flange. Alternatively, the retaining means comprises a retaining band, Preferably, the flange is provided with an undercut to receive the sealing means. Preferably the sealing means is a coded carrier bearing a code readable by a code reader in a coffee machine, More preferably, the sealing means comprises a bar code. Preferably, the sealing means comprises an expanded foam annulus. Preferably, the sealing means comprises a foil annulus.

The capsule of the invention provides a low cost capsule with a reliable seal that can also provide a code for use in an optical code reading capsule machine.

Exemplary embodiments of the invention will now be described with reference to the drawings, in which: Fig. 1 shows a perspective view of a first embodiment of the invention; Fig, 2 shows a perspective view of a second embodiment; Fig, 3 shows a perspective view of a third embodiment, Figure 1 shows a perspective side section of capsule 1 having a generally fmstoconical form, The upper end of the cone frustrum has a smaller diameter than the lower end. The surface of the upper end of the cone is provided with a zone of weakness in the form of an annulus. In use, cuffing members of the capsule machine will sit just above the annulus but do not pierce the capsule so that in use the water pressure bursts the weakened section and creates the path for the water to ingress the top of the capsule and into the coffee. In a manual machine that does not have cutting members, the water will simply tear or break the capsule at the zone of weakness.

If the capsule is made of a food grade plastic such as polypropylene, this arrangement substantially reduces air movement between the inside and the outside of the capsule thereby greatly extending the time that the coffee in the capsule retains its aromas. In use, the capsule should be fluted with nitrogen prior to being filled to prevent oxygen degrading the quality of the coffee. This in turn enables the producer to achieve an acceptable shelf life for the coffee without the use of a nitrogen filled pillow bag. In a particularly preferred embodiment the capsule wall is generally about 0.8mm thick but the wall around the zone of weakness is only about 0.5mm thick. The interior surface of the upper end has a small stepped profile in the region of the zone of weakness, so that the wall is thicker near the edge of the groove. This encourages the wall to tear near the centre of the groove or undercut rather than at the edge.

The lower end of the capsule is provided with a foil seal, which foil seal, in use, is pressed against a filter element typically comprising a plurality of the upstanding truncatedpyramidsandadaptedtoassistinthetearingofthefoiinusesothatthe coffee extracted from the coffee granules can percolate out of the capsule through holes in the filter.

The interior of the capsule is provided with several strengthening ribs to reduce the likelihood of the capsule collapsing under the pressures to which it is subjected in use.

The pressure on the inside of the capsule is typically in the range of 3 to 8 bar depending on the coffee machine and the packing density of the coffee in the capsule.

This pressure is sufficient to cause the foil to tear against a filter plate in the coffee machine.

The capsule is provided with a flange 4 at its lower end, which flange 4 is adapted to co-operated with a retaining mechanism of a coffee machine in use so that the capsule can be held in the correct position when in use in the coffee machine.

The flange 4 is provided with an undercut to receive a seal member 5, which seal member is provided th a bar code 6. Since many consumers wish to use their capsule machines for more than just espresso, a capsule recognition system can be advantageously included in the machine so that the machine can change the programme depending on the drink to be made. By including a barcode on the rim seal, the inclusion of the code on the capsule is greatly simplified compared to existing QR code and RFID tag solutions. It would be relatively straightforward to scan the capsule rim with a barcode reader as part of the closure process.

The seal member 5 can be made of a plastically deformable material such as expanded foam or aluminium foil and will have a height greater than the separation, in the extraction position, of the capsule cage and extraction plate of the coffee machine, The act of closing the capsule cage causes the seal to be crushed and plastically deformed thereby preventing leakage.

In this first embodiment, the seal member 5 is retained in position using a plurality of pips 7 on the capsule wall. The second embodiment is similar but has a plurality of pips 8 on an upstanding wall at the free edge of the flange. The third embodiment is provided with an annular retaining band 9 at the lower part of the capsule wall.

Although the capsule has been specifically described as being used to make espresso coffee, it would be possible to make other beverages such as tea or chocolate,

Claims

Claims 1. A capsule for use in a coffee or beverage machine having a generally frusto-conical form with an upper surface and a lower surface, an annular flange being provided at the lower surface, which annular flange is provided with sealing means on the surface facing towards the upper surface, wherein the sealing means comprises a detatchable annular element adapted to be plastically deformed when engaged by a capsule cage to thereby provide a seal between the capsule flange and the capsule cage, the annular element being retained in position by retaining means.
2. A capsule according to Claim t, wherein the retaining means comprises one or more retaining pips on the external capsule wall or on the free edge of the flange.
3. A capsule according to Claim 1, wherein the retaining means comprises a retaining band.
4. A capsule according to any one of Claims t to 3, wherein the flange is provided with an undercut to receive the sealing means.
5. A capsule according to any one of Claims I to 4, wherein the sealing means is a coded carrier bearing a code readable by a code reader in a coffee machine.
6. A capsule according to any one of Claims t to 5, wherein the sealing means comprises a bar code.
7, A capsule according to any one of Claims t to 6, wherein the sealing means comprises an expanded foam annulus.
8. A capsule according to any one of Claims 1 to 6, wherein the sealing means comprises a foil annulus
9. A capsule substantially as described herein with reference to and as illustrated in the accompanying drawing.