EP0448498B1 - Device for making coffee directly in a cup from roasted coffee powder contained in a bag - Google Patents

Abstract

Device for rapidly obtaining coffee directly in a cup according to standards which are close to a leaching (percolation) of real ground coffee. The porous bag-filter device containing a mass of prepared ground coffee adapted to extraction by hot water circulating under force inside it, by virtue of successive external pressures and relaxations which are applied to the mass of coffee via its envelope acting as a filter for the mass of ground coffee (6) contained, is made globally and reversibly compressible by the addition of multiple particles which are themselves reversibly compressible, the said particles being uniformly distributed in the mass of ground coffee so that the hot liquid, sucked or forced back (4 and 5) through the pores (7) circulates under force through the greater part of the ground coffee (6). The device is intended particularly for rapidly obtaining coffee and/or plant-based beverages. <IMAGE>

Description

The invention presented here consists of a special filter bag device for implementing a process for instant making of coffee by the user from real roasted and ground coffee.

Other aqueous extracts of plants which are difficult to obtain extemporaneously can also be made by this same process and device.

The process is summarized in a manual pumping action by means of a utensil, on a filter bag device with variable volume and reversibly compressible, containing ground coffee arranged in such a way that hot water passes in force through more much of the ground coffee mass present in the filter bag.

Indeed, among the plants usually consumed, obtaining liquid coffee requires a special extraction, because if we can count on the great solubility of tea and various herbal teas with conventional filter bags by a simple infusion, coffee as for he must usually undergo a "leaching" in a percolator or a filter placed in a funnel.

The so-called "leaching" operation forces boiling or very hot water to pass through a force or gravity layer of coffee powder, properly prepared and stored, to remove the active ingredients (caffeine, theophylline, theobromine) and others bitter or aromatic principles (several hundred identified by chromatography).

In addition, the consumer's taste is very precise and sensitive on this subject, this is why a new preparation process must give strictly equivalent flavor results, therefore respecting the type of extraction recognized as a reference, in this case the leaching.

A classic "infusette" with herbal tea is not sufficient for this operation because only small convection currents due to the temperature differences in the water are mobile in the plant powder to be infused provided that it is not too compact.

This implies that what is sufficient for tea, linden, verbena etc ... is unsuitable for ground coffee, because the moistened coffee powder is too compact to allow the hot water currents to pass easily when they are moved. by simple phenomena of density difference in relation to the local temperature of the water. In addition, since the ground coffee is made up of small grains, the pores of the filter bag must be small in diameter and easily clogged, which makes even more difficult the forced circulation of water.

Consequently, the entire active filter bag device must therefore act in the manner of a mechanical or biological suction-pumping "pump" by forcing water at high temperature through all the grains of powder. of coffee present so that they can transfer their active ingredients, bitter and fragrant, to the water, which corresponds to an action very close to leaching.

As for the preparation of an instant herbal tea by filter bag, the user must have in hand a cup filled with very hot water and a small spoon; in the process described here, he can use the latter to pump by pressing the bag against the wall of the cup.

This seemingly obvious action is only possible, however, if the filter bag can suck and discharge water under the action of the pressure of the spoon, which is impossible with the conventional structure of porous bags containing only a little plant powder because the compact coffee powder occupies a fixed, non-compressible volume. These observations therefore make it mandatory for the filter bag device, a structure with variable overall volume, that is to say compressible reversibly under an external mechanical action. The sachet will therefore contain, in addition to the ground coffee powder, means of making the overall volume compressible and advantageously hydrophilic to obtain a pumping effect on the liquid.

The action of the small spoon is cited as an example, but it is also possible to use any utensil and in particular a spoon pierced with holes to promote the circulation of water or a forceps-shaped instrument capable of pressing the compressible filter bag, so the user can make coffee for several people in any container.

Kinematics of the process :

It is an "artificial respiration" under the effect of the pressure of the spoon crushing a mass of composite ground coffee made compressible and hydrophilic, or the variable volume structure of the sachet itself, then letting them resume their initial volume upon release, which causes them to "expire" or "breathe in" hot water. This water having to pass at each time of the cycle on neighboring coffee particles, both at the suction and at the delivery, from the second pressure, it is already loaded with solubilized coffee coming from the previous pressures, thus giving increasing concentrations in the cup that we found in the darkness of the coffee, which allows to simply and visibly measure the strength and the "full-bodied". Likewise, the user has the possibility of bringing the sachet into an area of the cup where the liquid seems less black, that is to say less loaded with already dissolved coffee, thereby promoting the speed of extraction. .

One of the typical properties of this "respiratory" process lies in the fact that the coffee particles, which tend to close or seal the pores of the sachet on "expiration", will move and disperse again inward at " inspiration ", thereby unclogging the pores of the sachet to promote the next cycle (advantage over machine or funnel processes). Experimentation shows that a dozen pressures are often enough to obtain coffee that is practically identical to that made with a usual process and a conventional machine.

Pharmacology and organolentic characters :

As we know, the strength in caffeine is sought by some and feared by others: many coffees are precise mixtures of very aromatic "Arabica" varieties with little caffeine and very caffeinated "Robusta" varieties; such unitary sachets make it possible to offer, for example, various mixtures in the same box for different members of a family concerned about their nervous or cardiac health, or even "grands crus" for connoisseurs.

On the other hand, we know that the prolonged stay of very hot water in contact with the ground coffee beans promotes the extraction of caffeine, while a short stay in less hot water takes only the aroma. With such sachets, the user can therefore personalize his coffee by "pumping" slowly if he wishes a substantial level of caffeine, or on the contrary quickly if he is only looking for the aroma, while having the possibility of leaving the water temperature lower before placing the sachet.

History :

The first patents for coffee filters for coffee makers are very old and leaching is still used by hot water passing through a bed of ground coffee, either by pressure in a special machine ("espresso") or by gravity in a filter placed in a funnel, these devices having the general name of "percolators". On the other hand, it has only been for several decades that filter bags containing herbal teas have been used to make infusions, to the exclusion, however, of coffee and some difficult-to-extract plants such as cocoa for example; many improvements have been made in the texture and solidity of the porous paper used to make the bags or in the increase in exchange surfaces by special folding.

• DE 2715582 : "Dispositif pour la préparation d'une boisson, à partir de grains de café moulus, avec lequel le café moulu est versé dans un compartiment fermé, délimité au moins partiellement par des parois filtrantes et dispersé avec de l'eau chaude, caractérisé par le fait qu'après immersion dans une portion d'eau chaude ou après submersion avec de l'eau chaude, pendant la dispersion du café moulu, on peut faire varier le volume du compartiment ou de la chambre au moyen d'une poignée ou d'un élément de prise, afin de provoquer une circulation par effet de pompage. La poignée est structurée en forme de pince et avec les extrémités libres de ses bras, elle est en prise avec une section de paroi solide du sachet filtre."
• FR-A-2.140.753 : " Emballage, plus spécialement un récipient contenant du café torréfié moulu et du papier filtre, pour préparer un café-filtre caractérisé par le fait que le café torréfié moulu est séparé du papier filtre par une couche de séparation perméable à l'eau mais ne laissant pratiquement pas passer le café torréfié et dans lequel on place, dans le café torréfié, un corps contenant de l'air et absorbant l'eau, qui gonfle par absorption de l'eau, notamment un corps en éponge". Le corps en éponge est donc formé d'une matière compressible.
• EP-A-0226133 : "Sachet d'infusion en matériau filtrant, en particulier en papier filtre, pour la préparation de boissons dans un récipient à partir de substances se prêtant à l'extraction, notamment à partir de café grillé moulu, réalisé par pliage en forme de U du papier filtre en double couche de manière à obtenir réunies l'une à l'autre, par leurs extrémités supérieures, des branches délimitant des chambres partielles devant recevoir chacune une dose partielle de café grillé ou de quelque autre denrée analogue, caractérisé par le fait que les chambres partielles, ensemble avec leurs bords communs, sont réunies avec une poignée de manoeuvre rigide, de sorte que des déplacements vers le haut et vers le bas de la poignée de manoeuvre déterminent des déplacements transversaux de sens opposé des chambres partielles qui prennent appui sur un fond de récipient (fond de tasse) et à leur extrémité transversale supérieure, les chambres partielles sont réunies avec la poignée de manoeuvre et dans la zone de leurs bords inférieurs, elles sont réunies l'une à l'autre."

The state of the art can be defined by the following patents:

• DE 2715582: "Device for the preparation of a drink, from ground coffee beans, with which the ground coffee is poured into a closed compartment, delimited at least partially by filtering walls and dispersed with hot water, characterized in that after immersion in a portion of hot water or after submersion with hot water, during the dispersion of the ground coffee, the volume of the compartment or the chamber can be varied by means of a handle or a gripping element, in order to cause circulation by pumping effect. The handle is structured in the shape of a clamp and with the free ends of its arms, it engages with a solid wall section of the filter bag. "
• FR-A-2.140.753: "Packaging, more specifically a container containing ground roasted coffee and filter paper, for preparing a filter coffee characterized in that the ground roasted coffee is separated from the filter paper by a separating layer permeable to water but practically not letting roasted coffee and in which is placed in the roasted coffee, a body containing air and absorbing water, which swells by absorption of water, in particular a body in sponge ". The sponge body is therefore formed of a compressible material.
• EP-A-0226133: "Infusion bag made of filter material, in particular filter paper, for the preparation of drinks in a container from substances suitable for extraction, in particular from ground roasted coffee, produced by folding in U-shape of the double layer filter paper so as to obtain joined to each other, by their upper ends, branches delimiting partial chambers which must each receive a partial dose of roasted coffee or some other similar commodity , characterized in that the partial chambers, together with their common edges, are joined with a rigid operating handle, so that upward and downward movements of the operating handle determine transverse displacements of opposite direction partial chambers which are supported on a container bottom (cup bottom) and at their upper transverse end, the partial chambers are joined ies with the operating handle and in the area of their lower edges, they are joined together. "

Filter bag device according to the invention and means for making it active :

Since the sachet should be globally variable in volume and reversibly compressible for sucking and discharging the liquid, the following main suitable means must be used:
One can make the mass of ground coffee contained itself compressible and with variable volume, to cause a pump effect making circulate water everywhere through a mass or a bed of ground coffee. These types of actions on the overall volume can also be accompanied by favorable phenomena of water suction by surface tension if the materials used have hydrophilic properties in addition to their reversible compressibility.

Composite and compressible mass : To make the mass of ground coffee particles compressible, pieces of compressible material (spongy and hydrophilic, for example) are mixed with the coffee powder, which allows an overall variation in the volume of the filter bag under spoon pressure; all the coffee micro-particles are thus irrigated by a current of hot water sucked in or expelled at each cycle by the spongy materials, the coffee concentration increasing in the liquid as pumping actions progress.

Compressible or hydrophilic materials which can be used in dispersion in the mass of coffee (by way of non-limiting example): large strands of twisted wool, tangles of tangled textiles, carded or hydrophilic cotton, knitted fabrics of loose mesh, synthetic foams with open cells without parasitic odor etc ...

All these devices can be made with the usual reinforced papers with pores of smaller diameter than the coffee particles and will benefit from being put under vacuum in welded composite packaging to preserve the aroma and reduce the volume during storage.

The attached drawings are given as indicative and non-limiting examples. They represent a preferred embodiment according to the invention. They will allow the invention to be easily understood.

Figure 1 shows the pumping action of a compressible filter bag 1 against the wall of a cup 2 by a spoon 3 according to the method.

Figure 2 shows in three phases (rest, pressure, relaxation) depending on the variations of mechanical pressure applied, the movements of exit and entry of the liquid (4 and 5) through the walls provided with pores (7) and the movements of the coffee particles (6), showing that the particles are grouping around the pores when compressed by plugging them, but clear the passage and then disperse on suction.

FIG. 3 represents a preferred filter bag device (1) containing grains (8) of hydrophilic and compressible (spongy) material dispersed in the mass of ground coffee (6).

FIG. 4 represents various compressible or hydrophilic fillers (10) which can be dispersed in the mass of coffee (6).

All these versions of the basic device are given by way of examples and the materials or shapes can vary appreciably without departing from the scope of the invention, provided that the aim is achieved, which is to obtain a variable, reversibly compressible volume. and optionally hydrophilic for pumping and circulating the liquid around the coffee particles and that they are covered by claim 1.

According to FIGS. 3 and 4, the sachet (1) is conventionally made with a paper tube reinforced with fibers which cannot be disintegrated with water, this tube being closed by knurling to avoid any parasitic taste due to glue, for example.

This paper has pores (7) of smaller diameter than the particles of coffee powder (6) (however, the taste of certain consumers tolerating some particles in the bottom of the cup, "espresso" for example, the pores may be of a fairly large diameter allowing only a few of the smallest particles to pass through, which facilitates the circulation of the liquid).

A quantity of coffee powder (6), sufficient for a cup (2), is mixed with a substantially equal volume of hydrophilic and reversibly compressible particles (8) odorless and tasteless (or any other product forming a volume with elastic properties and hydrophilic), in such a way that the spongy particles (8) are regularly distributed in the mass of coffee (6), their particle size and their angular shape being studied so that no sedimentation of a component occurs with respect to the other subsequently, both dry and in water (diameter between 1 and 5 mm for example).

The paper tube is folded into a "U" shape according to use, filled with mixture, then closed by folding and stapling; a retaining wire is added as usual.

The sachet thus created has a slightly larger volume than conventional "teabags".

The filter bag is then placed in a bag of aluminum composite, for example, which is then welded under vacuum to preserve the preservation of the aroma, reduce the volume by crushing the sponge grains and prevent them from sedimenting. compared to coffee powder (the sponge beans regaining their normal volume when the sachet is opened and their function when they are soaked in hot water).

It is preferable to use pieces of spongy material previously saturated with coffee aroma by prolonged stay in coffee powder or in coffee extract, since such sponge beans tend to retain a part of the aroma during storage and not to release it during the simulated leaching, which does not happen if they are already saturated with aroma before being mixed with the final coffee powder and placed in the sachet .

The process and the family of devices, although very simple, are not obvious, because they must be adapted to the precise rules of the exhaustion of a mass or a bed of coffee particles as by a classic leaching. In addition, the combination of known teabags and simple means to make their volume variable and compressible causes a new technical effect of pumping liquid through the coffee particles without clogging the pores of the sachet and, thus, the easy extraction of the active ingredients. , bitter and aromatic balanced according to the usual taste, allowing almost instant confection of real coffee directly in a container or cup.

The devices seem susceptible of an industrial application "general public" if we consider the advantages, namely those, recognized, of the filter bags (maneuverability, lightness, speed of implementation), and those of the preservation of the taste of the true coffee combined with an easy dosage of strength and aroma.

The devices according to the invention are particularly intended for the rapid production of coffee and herbal drinks.

REFERENCES

1.

Filter bag

2.

Cup

3.

Spoon

4.

Liquid outlet and inlet movements

5.

Liquid outlet and inlet movements

6.

Coffee powder

7.

Pores

8.

Hydrophilic and reversibly compressible particles

10.

Compressible or hydrophilic fillers

Claims (6)

1. A porous filter bag device containing a mass of ground coffee or similar products, the mass being specially prepared and adapted particularly for extraction of active and aromatic substances by hot water which is circulating by force therein due to successive external pressing and releasing of the mass of coffee, through its casing serving as a filter,
   characterized in that the mass of ground coffee (6) contained, which normally is incompressible, is made compressible in a global and reversible way by adding multiple particles which are reversibly compressible themselves, said particles being spread regularly throughout the mass of ground coffee, so that the hot liquid, which is drawn in or forced back (4 and 5) through the pores (7) by variation in the volume of the compressible particles undergoing the external pressing and releasing, circulates by force through most of the ground coffee (6) thereby moistening all the adjacent microparticles of coffee, so as to be loaded with more and more active or aromatic substances at every cycle of pressing and releasing executed upon the mass.
2. A device according to claim 1,
   characterized in that the compressible particles spread regularly throughout the mass are advantageously saturated with coffee aroma so that they will not extract any from the coffee powder itself during storage.
3. A device according to claim 1,
   characterized in that the means for making the mass of coffee reversibly compressible consist of multiple reversibly compressible and hydrophilic particles (8) which are spread out and dispersed regularly in the mass of ground coffee (6) placed in the bag (1), which gives the composite mass itself a variable global volume and enables it to draw in or force back the liquid under the influence of successive external pressing executed upon the mass.
4. A device according to claim 1,
   characterized in that the means for making the mass of coffee reversibly compressible consist of multiple compressible, non-hydrophilic particles (8) spread out and dispersed regularly in the mass of ground coffee (6) placed in the bag (1), which gives the composite mass a variable global volume and enables it to draw in or force back the liquid by itself under the influence of successive external pressing executed upon the mass.
5. A device according to claim 1,
   characterized in that the means for making the entire mass compressible consist of natural or synthetic textile fibres (10) which are twisted, loose or else form flocks or pieces of loosely woven, elastic textiles, tending to regain their initial volume after being compressed, and which are spread out and mingled regularly within the mass of ground coffee (6) placed in the bag (1), which gives the composite mass a variable global volume and enables it to draw in or force back the liquid by itself under the influence of successive external pressing executed upon the mass.
6. A device according to claim 1,
   characterized in that it comprises a flap or valve system (18) housed in an attached part forming a pump.

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