GB2577948A

GB2577948A - Coffee bag

Info

Publication number: GB2577948A
Application number: GB1821101.1A
Authority: GB
Inventors: Gort-Barten Alex; Alexander Gort-Barten Leslie
Original assignee: Individual
Current assignee: Individual
Priority date: 2018-10-11
Filing date: 2018-12-21
Publication date: 2020-04-15
Anticipated expiration: 2038-12-21
Also published as: GB201821101D0; GB2577948B; GB2577924B; GB2577924A; GB201816574D0

Abstract

A porous infusion packet (such as a coffee or tea bag for example) comprising a plurality of holes adjacent a seam wherein the holes have a diameter between 0.1mm and 0.4mm. Ideally, the seams are ultrasonically welded (preferably double welded). The porous material may be a filter paper. The packet ideally comprises between 10 and 100 holes which may be arranged in two and three lines around a centreline of the packet. The holes may be offset from one another or may be distributed across the surface of the packet.

Description

Coffee Bac] The invention relates to an infusion packet, in particular a coffee bag Consumer demand for proportioned coffee has grown significantly in recent years as they recognise the convenience and lack of messy grinds compared to conventional filter coffee.

ESE coffee pods are long established and 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 capsule 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. High Pressure systems such as Nespresso ® have the largest market share but are only able to produce an "americano" long coffee, being otherwise designed for espresso. A number of low pressure systems such as Senseo 0, Tassimo0 or Keurig have been commercially successful in some markets but tend to produce a fairly bland product due to the fast extraction time and low pressures.

Many varieties and blends of coffee do not lend themselves to use in such machines as they require a longer brewing time and are not able to tolerate the high temperature and pressure of the Nespresso system for example.

For many years tea bags were typically flat and available primarily as square or round sheets of porous filter material with infusible material such as tea leaves or herbal leaves sandwiched between the sheets. The infusion performance of such packets is limited, which led to the development of tetrahedral-shaped packets such as those disclosed in WO 95/01907.

Infusion packets for coffee or coffee bags have been provided for many years, eg GB19164, but have never been commercially successful in contrast to tea bags, which dominate the tea market, due to problems with the extraction of the coffee.

The present invention therefore seeks to provide an improved infusion packet for coffee or coffee bag.

According to the invention there is provided an infusion packet for coffee in accordance with the features of Claims 1 or 4.

Preferred aspects of the invention can be found in the sub-claims. The infusion packet comprises a porous material, ground coffee being sandwiched between first and second surfaces of the porous material, wherein the ground coffee has a first volume and the infusion packet has a second volume, the difference between the first and second volumes defining a packet headroom, wherein the packet headroom is at least 55% of the second volume Traditionally, when making filter coffee a little water is poured on the coffee, enough to soak the beans, and then around 45 seconds allowed to pass to allow the coffee gases to be released before completely covering the coffee with water. This is called the bloom period. The provision of extra head room in the bag advantageously allows the gases to be released if the bag is fully immersed without a bloom period and permits the coffee to emulsify faster in the water to give a fuller flavour in the cup in comparison to the known coffee bags.

Exemplary embodiments of the invention will now be described with reference to the drawings, in which: Fig. 1 shows a known coffee bag Fig. 2 shows the coffee bag of Figure 1 under extraction Fig. 3 shows a coffee bag according to the invention Fig. 4 shows the coffee bag of Fig. 3 under extraction Fig. 5 shows a size distribution for a grind for the coffee bag Fig. 6 shows a blank for a further embodiment of the coffee bag Figure 1 shows a known coffee bag 1 made of a filter paper having a generally rectangular shape with a surface area on each face of 21cm2 and containing 7.8 grams of coffee. Further dimensional details are provided in the table below. The coffee is evenly packed.

Figure 2 shows the coffee bag 1 under extraction in hot water. The immersion of the coffee bag 1 in the hot water causes the coffee in the bag to expand and also to release carbon dioxide. The expansion of the bag causes this to bulge and the release of the carbon dioxide causes the bag to float on the surface of the water with approximately 25% of the expanded bag being above the surface of the water. The inventor has identified two mechanisms preventing an efficient extraction of the coffee. The first is that some of the coffee is above the water and hence cannot be extracted unless the bag is pushed down with a spoon, which may cause the bag to break. The second is that the coffee in the bag has expanded and is no longer able to freely move within the bag, which again reduces the efficiency of the extraction.

Figure 3 shows a coffee bag 2 in accordance with the invention, which is made from a similar filter paper to the coffee bag of Figure 1. The coffee bag 2 has a pyramidal structure with exemplary dimensions given in the table below. The pyramidal bag 2 is loosely packed with coffee in comparison to the coffee bag 1.

Figure 4 shows the coffee bag of Figure 3 under extraction. The carbon dioxide released by the coffee during extraction tends to rise, so that the coffee bag orients itself with one vertex being oriented towards the bottom of the extraction vessel and at least one of the remaining vertices or faces being lifted slightly clear of the water by the carbon dioxide escaping. Due to the greater volume of the bag, the expanding coffee particles are free to move within the bag. The extraction process is therefore more efficient as more of the coffee is extracted. The orientation of the coffee bag also leads to the coffee remaining below the surface of the water, which further enhances the extraction efficiency.

The table below provides some exemplary dimensional data Table 2 below provides data on the grind: Figure 5 shows the distribution of particle sizes in a particularly preferred embodiment. A conventional filter grind comprises 50-70%+ of particles having a distribution pattern with a single peak at or above 800pmi1 00 pm. The particle distribution shown in Figure 5 has a first peak at 500pm±100 pm and a second at 800pm±100 pm. The first peak corresponds to approximately 30% of the sample and the second peak corresponds to approximately 35% of the sample. The inclusion of the smaller particle size appears to aid particle movement within the bag.

Figure 6 shows a blank for a further embodiment of the coffee bag in which a plurality of holes are shown in the blank. The blank can be made from a non woven material. The holes are arranged substantially in lines, in which the holes are generally spaced from one another on the line. On the left and right hand edges of the blank, there are two lines of holes and three lines of holes are arranged around the centreline of the blank. The holes in adjacent lines are arranged offset from the holes in the

Prior art

Square Bag Large filtMid Bag 8.00 7.00 7.00 6.80 6.30 6.00 Are rlik2) 27.20 22.05 21.00 voturne (ni) 61 65 46.31 42.00 Headroom tmg 43.04 27.69 20.12 Headroom t% of Total Bag Volume, Pyramid Grind

Prior Art Sc; u are Bag

Coffee Density 0.40 0.36 (gicmA3) Coffee Qua ntity 7.50 7.80 Coffee V olume (m1) 18.61 21.88 neighbouring line. The holes are preferably in the range of 0.1 to 0.4mm.

Preferably, there are between 10 and 100 holes per blank.

It would also be possible to use a woven porous material. The holes may also be distributed across the surface of the coffee bag.

When the bag is formed from the blank, the holes will be arranged in the vicinity of the seams of the coffee bag. For the case that the seams are ultrasonically welded, typically ultrasonically double welded, along their edges, the provision of the holes surprisingly strengthens the weld by reducing pressure on the seam during the coffee extraction. Advantageously the coffee can also dilute more quickly.

Claims

Claims 1 An infusion packet comprising a porous material, which packet is closed with seams, wherein the material is provided with a plurality of holes of between 0.1 and 0.4mm adjacent to the seams.
2. An infusion packet according to Claim 1, wherein the seams are ultrasonically welded.
3. An infusion packet according to Claim 2, wherein the seams are ultrasonically double welded.
4. An infusion packet according to any one of Claims 1 to 3, wherein the porous material comprises a filter paper.
5. An infusion packet according to any one of Claims 1 to 4, wherein the packet comprises between 10 and 100 holes.
6 An infusion packet according to any one of Claims 1 to 5, wherein there are two lines of holes and three lines of holes are arranged around the centreline of the packet.
7. An infusion packet according to any one of Claims 1 to 6, wherein the holes in adjacent lines are arranged offset from the holes in the neighbouring line.
8. An infusion packet according to any one of Claims 1 to 5, wherein the holes are distributed across the surface of the coffee bag.