Patent Application
20150140179
The present invention concerns infusion packets, and also methods for producing such packets. In particular, the present invention relates to infusion packets containing infusible material such as tea.
In the past, conventional infusion packets (e.g. tea bags) have typically been flat, comprising a single chamber filled with infusible material (e.g. leaf tea, herbal mixtures). This type of packet often comprises infusible material sandwiched between square or round sheets of porous material. Such packets restrict the movement of the infusible material within the packet to substantially two dimensions. As a result, the infusion performance of such packets is limited.
Double-chamber infusion packets such as those described in U.S. Pat. No. 2,593,608 (A.G.F. Rambold) are also known. In such infusion packets, the infusible material is contained in two chambers, with each chamber being attached to the other at the base and apex. This type of infusion packet is thought to enable faster infusion by allowing an increased flow of water around the infusible material. However, a drawback of double-chamber infusion packets is that they require significantly more porous packet material than their single-chamber counterparts.
GB 2 053 668 (H. C. Fornari) describes the use of disposable sachets in the preparation of infusions of tea, coffee and other similar infusible substances. The shape of the sachets is generally that of an elongated double wedge. The sachets are elongate because they are designed to be gripped at their upper end, while their bottom end is dipped into a vessel which contains water. The elongate nature of these sachets means that they require a considerable amount of packaging material.
Thus there is a need for an infusion packet which overcomes or ameliorates one or more of the aforementioned disadvantages.
In a first aspect the invention relates to an infusion packet comprising a top, a bottom, a first side and a second side; wherein the bottom of the packet is defined by a gusset and each side of the packet is defined by a seal that extends between the top and bottom of the packet; wherein the seals defining the sides of the packet are arranged such that the packet has a compartment with a substantially trapezoidal cross-section.
Such a packet is substantially flat prior to use and hence convenient to pack and handle. However, the packet can nonetheless swell upon immersion in an infusion liquid such that it adopts a more three-dimensional shape. This swelling is thought to permit an increased flow of the infusion liquid around the infusible material and hence facilitate faster infusion. In order to further facilitate swelling of the packet, it is preferred that the packet comprises two gussets (i.e. a first gusset defining the bottom of the packet and a second gusset defining the top of the packet).
The packet of the present invention has a compartment which preferably contains a substance, more preferably a particulate substance (e.g. an infusible material such as tea leaves and/or stem).
The combination of the shape of the compartment together with the presence of the gusset(s) is thought to encourage the substance to collect towards the bottom of the packet. Hence the filled packet can maintain an upright position, particularly when in use (i.e. when immersed in an infusion liquid). Without wishing to be bound by theory, we believe that this is due to the filled packet having a low centre of gravity. This may help to keep the substance (e.g. tea leaves and/or stem) submerged in the infusion liquid. Additionally or alternatively, the low centre of gravity together with the presence of the bottom gusset enables the packet to stand upright for display purposes (e.g. during presentation and selection).
In a second aspect the invention relates to a method of manufacturing an infusion packet from a web of packaging material, the method comprising the steps of:
The method permits the manufacture of infusion packets according to the first aspect of the invention whilst incurring substantially no wastage of packaging material.
In order to produce individual packets, it is particularly preferred that the method comprises the additional step of:
From the point of view of a consumer, it is believed that the packets are perceived to be premium quality due to their exciting shape. As such, the method permits the manufacture of a premium product at a competitive cost.
As used herein the term “comprising” encompasses the terms “consisting essentially of” and “consisting of”. It should be noted that in specifying any range of values or amount, any particular upper value or amount can be associated with any particular lower value or amount. The disclosure of the invention as found herein is to be considered to cover all embodiments as found in the claims as being multiply dependent upon each other irrespective of the fact that claims may be found with multiple dependency or redundancy.
As used herein the term “trapezium” refers to a convex quadrilateral with one pair of parallel sides and one pair of non-parallel sides. A “trapezoidal cross-section” refers to a cross-section that has the shape of a trapezium. A trapezium in which the two non-parallel sides are of equal length is referred to as an “isosceles trapezium”. For the avoidance of doubt, it is noted that an infusion packet according to the present invention has a compartment with a substantially trapezoidal cross-section when viewed from the front or the rear of the packet.
Since the packet of the present invention is an infusion packet, it is preferred that the packet is formed from porous packaging material. As used herein the term “porous packaging material” is used to describe a water-insoluble, liquid-permeable packaging material which has openings that permit liquids, especially aqueous liquids, to pass through. Suitable packaging materials include non-wovens, wet laid non-wovens and wovens made with polymers of cellulosic/polymer blends (e.g. cellulose or cellulose PP blends) or perforated films.
The packaging material may be heat-sealable or non-heat sealable. In order to facilitate a high rate of infusion packet manufacture, in a preferred embodiment the packaging material is heat-sealable.
As used herein the term “beverage” refers to a substantially aqueous drinkable composition suitable for human consumption.
The packet of the present invention preferably contains infusible material. As used herein the term “infusible material” refers to a food-grade substance that when steeped or soaked in an aqueous liquid releases certain soluble substances into the liquid, e.g. flavour and/or aroma molecules. As such, the infusible material can be contacted with an aqueous liquid such as water to provide a beverage. This process is referred to as brewing. Brewing may be carried out at any temperature but is preferably carried out at least 40° C., more preferably at least 55° C., more preferably still at least 70° C. and preferably less than 120° C., more preferably less than 100° C., more preferably still less than 90° C., most preferably less than 80° C.
It is preferred that the infusible material is at least partially insoluble (i.e. does not dissolve completely when steeped or soaked in water).
The infusible material preferably comprises plant material. For example, the infusible material may comprise plant material derived from Camellia sinensis, Aspalathus linearis, Mentha piperita, Matricaria recutita and/or mixtures thereof.
In a preferred embodiment, the infusible material comprises tea material. As used herein the term “tea material” refers to material derived from the plant Camellia sinensis var. sinensis and/or Camellia sinensis var. assamica.
The tea material may have been subjected to a “fermentation” step wherein the tea material is oxidised by certain endogenous enzymes that are released during the early stages of “black tea” manufacture. This oxidation may even be supplemented by the action of exogenous enzymes such as oxidases, laccases and peroxidises. Alternatively the material may have been partially fermented (“oolong tea”) or may have remained substantially unfermented (“green tea”).
In a particularly preferred embodiment the infusible material comprises tea leaves and/or stem. As used herein, the term “tea leaves and/or stem” refers to tea material that is derived from the leaves and/or stem of the tea plant and that has not been subjected to an extraction step.
As mentioned above, the packet of the invention is preferably a porous infusion packet which contains infusible material. In a particularly preferred embodiment, the infusible material comprises tea material, more preferably tea leaves and/or stem. Such a packet can be used to prepare a tea-based beverage, e.g. by contacting the infusion packet and its contents with an aqueous liquid (i.e. brewing). As used herein the term “tea-based beverage” refers to a beverage comprising at least 0.01% by weight dissolved tea solids. The term “tea solids” refers to dry material that is extractable from tea leaves and/or stem, and which is soluble in boiling water.
Certain embodiments of the invention are illustrated by the figures, in which:
a is a front view of an infusion packet according to an embodiment of the invention;
b is a rear view of the packet of
c is a cross-sectional side view of a preferred embodiment of the packet shown in
a to 3d are a series of perspective front views showing steps in the formation of a packet according to an embodiment of the invention;
a and 4b are perspective front views showing packets being made according to an embodiment of the invention;
a is a front view of a packet according to an alternative embodiment the present invention;
b is a rear view of the packet of
a is a cross-sectional side view of an embodiment of the packet of
b is a cross-sectional side view of an alternative embodiment of the packet of
a shows an apparatus which is suitable for producing packets according to the present invention; and
b and 7c show cross-sectional views of alternative embodiments of the conduit outlet of the apparatus of
a to 1c show three different views of an infusion packet as per a preferred embodiment of the present invention.
a shows an infusion packet 1 viewed from the front, wherein the packet 1 has a top 2, a bottom 3, a first side 4 and a second side 5. The packet 1 has a front face which consists of a trapezium-shaped front panel 6. In this embodiment, the sides of the packet 4, 5 are arranged such that the front panel 6 has the shape of an isosceles trapezium. Each side 4, 5 is defined by a seal that extends between the top 2 and bottom 3 of the packet. In this preferred embodiment each seal has a substantially uniform breadth. However in certain other embodiments one or both of the seals may have a variable breadth (see, for example,
The top 2 and the bottom 3 of the packet are substantially parallel to one another and are separated by a distance D. The magnitude of the distance D will depend on the intended use of the packet. For example, in a particularly preferred embodiment where the packet is an infusion packet, it is desirable that the packet will fit in a cup, a mug and/or a teapot. Thus in such an embodiment, the distance D is preferably no more than 85 mm, more preferably no more than 70 mm, still more preferably no more than 65 mm and most preferably no more than 60 mm.
It is preferred that the infusion packet is able accommodate sufficient infusible material to produce a flavourful beverage, for example preferably from 1 to 5 g of infusible material, more preferably from 1.3 to 4 g and most preferably from 1.6 to 3 g. In order to allow the infusion material room to move and/or improve the flow of water around the infusible material, it is preferred that the distance D is at least 30 mm, more preferably at least 35 mm, still more preferably at least 40 mm and most preferably at least 45 mm.
b shows a view of the infusion packet of
In the infusion packet shown in
The size of W1 and W2 will depend on the intended use of the packet. For example, it may be desirable that the infusion packet will fit in a cup, a mug and/or a teapot and/or that the packet is able accommodate sufficient infusible material to produce a flavourful beverage. W1 is preferably from 30 to 80 mm, more preferably from 35 to 75 mm, most preferably from 40 to 70 mm. W2 is preferably from 20 to 70 mm, more preferably from 25 to 65 mm, most preferably from 30 to 60 mm.
So long as W1 is wider than W2, the sizes of W1 and W2 may be selected independently of one another. For example, if the intention is to provide an infusion packet suitable for a teapot, an infusion packet wherein W1 is 80 mm and W2 is 20 mm is envisaged, as is an infusion packet wherein W1 is 80 mm and W2 is 60 mm.
c shows a cross-sectional side view of a preferred embodiment of the infusion packet of
In this preferred embodiment each gusset 11, 12 is “M”-shaped, and consists of two gusset panels 13. An outer crease 14 defines a boundary between a gusset panel 13 and a front panel 6 or a back panel 7, 8. An inner crease 15 defines a boundary between two gusset panels 13.
More generally, a gusset defining the top 2 or bottom 3 of the packet consists of:
The size of the gussets 11, 12 is not fixed, and will depend on several factors such as the magnitude of the distance D, and the amount of infusible material contained within the packet.
It is preferred that that each gusset panel 13 has a width (i.e. distance between the outer crease 14 and the inner crease 15) of no more than 20 mm. Preferably each gusset panel 13 has a width of from 3 to 20 mm, more preferably from 4 to 12 mm and most preferably from 5 to 8 mm.
In embodiments where the gusset(s) are “M”-shaped, it is preferred and the total width of each gusset 11, 12 (i.e. the distance between the two outer creases 14 when the gusset is fully extended) is no more than 40 mm. Furthermore, each “M”-shaped gusset 11, 12 preferably has a total width of from 6 to 40 mm, more preferably from 8 to 24 mm and most preferably from 10 to 16 mm.
The presence of the gusset(s) means that the infusion packet can swell upon immersion in an infusion liquid so as to adopt a more three-dimensional shape. This swelling is thought to permit an increased flow of the infusion liquid around the infusible material and hence facilitate faster infusion. Although infusion packets which adopt a three-dimensional shape are already known (e.g. tetrahedral-shaped packets such as those described in WO 95/01907), the inherent three-dimensional nature of such packets means that they are somewhat inconvenient to pack and handle. By contrast, the infusion packets of the present invention are substantially flat prior to use and thus can be packaged more conveniently and/or efficiently.
As described previously, the boundary between the two back panels 7, 8 is preferably defined by the longitudinal seal 9. In the embodiment shown in
The web 21 of packaging material has edges 22, 23 separated by a width B. Each packet comprises a portion of the web 21, although the web itself can be of indefinite length. The portion of the web 21 from which a single packet is ultimately formed is delimited from adjacent portions of the web 21 by side boundaries 24. The side boundaries 24 extend across the full width B of the web in the embodiment shown.
As shown in
Edge margins 16, 17 extend along the edges 22, 23 of the web 21 of packaging material. When packets are formed, the edge margins 16, 17 are incorporated in the longitudinal seal 9. The longitudinal seal defines the boundary between the two back panels 7, 8 (see, for example,
The web 21 of packaging material shown in
A single infusion packet comprises packaging material that covers an area A. The area A is a convenient measure of the amount of packaging material required to form each packet. In order to minimise environmental impact, it is desirable to limit the amount of packaging material used to form each packet. However, the amount of packaging material used to form a packet should ideally not be restricted to such an extent that undue force is exerted on the seals since this could cause the seals to split resulting in unwanted release of the package contents. Additionally or alternatively it is undesirable to restrict the amount of packaging material to such an extent that the infusion performance of the packet is compromised.
Thus in order to balance environmental impact, packet integrity and/or infusion performance, a single infusion packet according to the present invention preferably consists of packaging material that covers an area A of less than 12000 mm2. Preferably A is from 5000 to 11000 mm2, more preferably from 5500 to 9500 mm2 and most preferably from 6000 to 8000 mm2.
a to 3d are a series of perspective views which illustrate a sequence of process steps that can be carried out to form an infusion packet from a continuous web of packaging material.
Firstly, the edge margins 16, 17 of the web are sealed together with a longitudinal seal 9 to give the web a tubular form, and the tubular web is indented so as to introduce creases that define one or more gusset(s). For example,
The web travels vertically (downwards) to a sealing zone where seals 31 that define the individual packets are formed. A seal 31 is formed comprising the side margins 25 of the web of packaging material such that the seal 31 defines a first side wall 32 of the present packet and a second side wall 33 of the preceding packet (
As shown in
The chain of packets is subsequently separated into individual packets by severing the web at the seals 31 along the side boundaries 24 as shown in
In an alternative embodiment (not shown), it is possible to seal and cut in a single operation rather than having these operations performed serially.
a and 4b show a preferred means of producing infusion packets according to the present invention.
a is a perspective view which illustrates a chain of infusion packets. Each packet comprises a top wall, a bottom wall, a first side wall 32 and a second side wall 33.
b is a perspective view illustrating the formation of individual packets from the chain of infusion packets shown in
a and 5b show two different views of an infusion packet according to an alternative embodiment of the present invention.
a shows an infusion packet 51 viewed from the front, wherein the packet 51 has a top 52, a bottom 53, a first side 54 and a second side 55. Each side 54, 55 is defined by a seal that extends between the top 52 and bottom 53 of the packet.
The packet 51 has a front face which consists of a substantially rectangular front panel 56. Nevertheless, the arrangement of the seals ensures that the packet has a compartment which is substantially trapezoidal in cross-section when viewed from the front or back. As such, in this embodiment the seals have a variable breadth, wherein the breadth of the seal is wider at the top 52 of the packet than it is at the bottom 53.
The top 52 and the bottom 53 of the packet are substantially parallel to one another and are separated by a distance D. As described above, the magnitude of the distance D will depend on the intended use of the packet.
b shows a view of the packet of
In the embodiment of the packet shown in
a and 6b are cross-sectional side views of two alternative embodiments of infusion packets.
a shows a cross-sectional side view of an infusion packet, such as the infusion packet of
In this embodiment the gusset 61 is “M”-shaped, and consists of two gusset panels 63, two outer creases 64 and one inner crease 65. As described previously, each outer crease 64 defines the boundary between a gusset panel 63 and the front panel 56 or the back panel 57, 58; while the inner crease 65 defines the boundary between the two gusset panels 63.
In order to form an infusion packet comprising a single gusset, the process of
It should be noted that while the packet of
b shows a cross-sectional side view of an alternative embodiment of an infusion packet (e.g. the packet of
a illustrates an embodiment of an apparatus for manufacturing packets according to the present invention, for example the apparatus can implement the process shown in
The apparatus has a single production path being supplied with a substance 70 (such as infusible material) by a doser (not shown). A web of packaging material 71 is fed over a shaping guide near an inlet 72 of a conduit 73. Preferably the conduit inlet 72 has a circular cross-section. Here the web takes up the tubular form of the conduit exterior and is drawn down the tube by one or more guide elements 74 while its opposite edge margins are sealed together longitudinally by a longitudinal sealer 75. In a preferred embodiment, the longitudinal sealer 75 is adjacent to the conduit and in a particularly preferred embodiment the longitudinal sealer 75 comprises a pair of heating and pressing rollers that weld the side margins together to form a longitudinal fin seal 79.
The tubular web is drawn along the conduit 73 and past an outlet 76 of the conduit, preferably by the guide elements 74. Preferably, the conduit outlet 76 has an external cross-section comprising at least two vertices 77 (see
The tubular web is indented between the vertices 77 by at least one forming member 78. Preferably the forming member(s) 78 are situated adjacent to the conduit outlet 76. For example,
The apparatus of
b and 7c show cross-sectional views of alternative embodiments of the conduit outlet of the apparatus of
The conduit outlet 76 has an internal cross-section and an external cross-section which can be the same shape (see
The conduit preferably transitions from having a circular cross-section (both externally and internally) at its inlet 72 to having an external cross-section at its outlet 76 that comprises at least two vertices 77. More preferably the external cross-section of the conduit outlet 76 comprises at least two vertices 77 that delimit a face, and in especially preferred embodiment, such as the ones illustrated in
In order to maximise the flow of infusible material through the conduit, in certain embodiments it is preferred that the internal cross-section of the conduit outlet is the same shape as the external cross-section, for example as illustrated in
It may be desirable to prevent accumulation of infusible material at the vertices of the internal cross-section of the conduit outlet 76. Therefore, in certain alternative embodiments, the internal cross-section of the conduit outlet 76 may comprise fewer vertices than the external cross-section, for example as illustrated in
In the apparatus illustrated in
The progress of the tubular web, which preferably moves at a substantially uniform speed, and the timing of the sealing elements are adapted such that the widths W1 and W2 between successive seals are of appropriate sizes.
The indented tubular web is filled with doses of infusible material as it is formed into a chain of packets defined by the seals 31. In a preferred embodiment, an input device delivers the infusible material via the conduit such that each sealed compartment comprises a single dose of infusible material. The compartmented tubular web is subsequently separated into individual packets by severing the web at the seals 31. In an alternative embodiment, it is possible to seal and cut in a single operation rather than having these operations performed serially.
The web of packaging material 71 may be heat-sealable or non-heat sealable. In order to facilitate a high rate of infusion packet manufacture, in a preferred embodiment the packaging material is heat-sealable.
| Number | Date | Country | Kind |
|---|---|---|---|
| 12168881 | May 2012 | EP | regional |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/EP2013/060136 | 5/16/2013 | WO | 00 |
