Field of the Invention
[0001] This invention relates generally to a method for packaging a beverage powder tending
to evolve a gas in a beverage capsule. It also relates to a beverage capsule so produced.
In particular, this invention relates to such capsules as adapted for coffee beverages.
Background
[0002] Coffee beans, before being used to prepare a coffee beverage, must generally be roasted.
This process induces numerous chemical reactions and physical changes within the coffee
beans, which must be accounted for when packaging the roasted coffee.
[0003] The roasting process is what produces the characteristic flavor of coffee by causing
the green coffee beans to expand and to change in color, aroma and density. The oils
and aromatic volatiles contained and/or developed during roasting confer the aroma
and flavor of the coffee beverage produced therefrom, but are also prone to degradation
when exposed to the oxygen in the surrounding air. It is thus important to protect
the roasted coffee from the surrounding air, to maintain optimal freshness and shelf
life. The roasting process also causes the production of gases within the coffee beans,
primarily carbon dioxide and carbon monoxide. These gases are slowly evolved by the
coffee subsequent to roasting in a process called "degassing." Grinding the roasted
coffee beans will accelerate this process.
[0004] Recently, it has been common to base beverage production systems on the principle
of portioned beverages; that is, providing a pre-determined volume of a beverage upon
demand. This has been typically accomplished by providing a capsule, which contains
a pre-portioned amount of a beverage powder, most commonly ground coffee. Hot water
is then introduced into the capsule to prepare the beverage, which is then dispensed
into a container for consumption. Before use, the capsule can be hermetically sealed
under vacuum or controlled atmosphere such as mentioned in
WO8602537 to reduce oxidation by the contact of coffee with air. While this specification refers
to a "capsule," it is understood those other terms, such as "pod," "cartridge," or
"packet" may be employed instead.
[0005] Such capsules may be configured so as to be hermetically sealed up until use. It
is evident that by such hermetical sealing, it is meant that a gas transfer is not
made possible in any direction between the inside of the capsule and the external
atmosphere at least for many months. This is desirable, as the capsule will prevent
the essential oils present in the coffee from degradation caused by contact with oxygen
in the air. This improves the flavor and shelf life of the coffee within such a capsule.
It is also evident that due to its hermetical closure, the capsule is configured for
a single use.
[0006] However, as described above, coffee will evolve gas after roasting. When the ground
coffee is packaged in a sealed container, the container will trap any gases evolved
by the coffee contained within, which in some cases may cause the container to rupture
under the pressure generated by the evolved gas. The container must be constructed
more robustly, requiring more materials for its construction and increasing the cost
of its fabrication.
[0007] To avoid this, the coffee is held aside for a period of time, allowing substantially
all of the gases to be released from the coffee before it is packaged in containers.
This process is known in the art as "degassing." By degassing the coffee beforehand,
one may avoid the evolution of gas within the sealed container and the accompanying
accumulation of pressure.
[0008] However, the step of degassing beforehand coffee causes a loss of aromatic compounds.
This aroma loss reduces the aroma intensity and modifies the aromatic profile of the
final beverage obtained from the extraction of the beverage capsule.
[0009] The degassing process is generally accomplished by the use of degassing silos or
buffers, within which the coffee is stored while it degasses. The silos are generally
provided with means for removing the evolved gases, and may optionally be provided
with means for introducing an inert gas. This inert gas, generally nitrogen, excludes
oxygen from the silos and prevents degradation of the coffee.
[0010] One must store the degassing coffee within these silos for as long as is necessary
to evacuate a sufficient amount of gas. For ground coffee, the degassing time is usually
between 30 and 60 minutes for a partial degassing to 24 hours or more for a full degassing.
However during degassing, a large part of volatiles aromas of the coffee are lost,
diminishing the flavor and the aroma of the coffee beverage.
[0011] Of course, degassing of the coffee cannot be totally eliminated between the grinding
and the sealing of the capsule since the coffee must be transported from the grinding
area to the filling and sealing areas. This "transport degassing" is dependent on
the production line capacity.
[0012] WO2008129350 refers to a machine for packaging capsules in a vacuum and/or in a controlled atmosphere.
After filling with coffee, the capsules are partially closed by an hermetic film.
Then, a vacuum is formed inside the capsules and sealed by a thermo-sealing vacuum
device. Optionally, an inert gas can be inserted in the capsule after drawing a vacuum
to fill the headspace of the capsule with a controlled atmosphere. This invention
does not deal with a better preservation of the aroma of the packaged product. In
particular, there is no indication that the degassing of the product is minimized
before the capsule is hermetically sealed and gas is kept emanating into the cavity.
[0013] In
US3077409, the invention seeks to eliminate the holding (degassing) period for coffee before
packing it. It so relates to a coffee package with a self-venting reclosure can. The
coffee is immediately filled into the can, thus omitting the conventional holding
cycle. The filled can is then closed under vacuum. The can comprises a valve means
permitting a portion of the gas within the container to pass. However, the problem
of preserving aroma is not tackled since the evolving gas is allowed to escape out
of the capsule.
[0014] US4069349 refers to a process for vacuum packaging of roasted ground coffee in pouches. The
pouches are partially sealed, with a tortuous unsealed passage, and then stored for
a predetermined period of time to permit the gases to evolve from the pouches and
then sealing the pouches to prevent further gaseous passage to and from the product.
The degassing of the product outside the pouch causes the loss of aromatic compounds.
[0015] WO2011039711 relates to a method and machine for packing infusion product into capsules; the machine
comprising a series of station for manipulating, filling, sealing and overwrapping
the capsules and all enclosed within a zone in controlled atmosphere (using nitrogen,
for example) so as to preserve the chemical and physical qualities of the product,
for example, aroma in the coffee. However, there is no reduction of degassing of the
product before sealing and overwrapping the capsule; no vacuum is drawn in the package
before sealing and no degassing of the product is contemplated in the package to an
extent above the atmospheric pressure.
WO2010007633 refers to a machine for packaging products, in particular capsules for machines for
delivering infusion beverages. A vacuum bell provides vacuum around each capsule to
be welded. At the same time, vacuum compensating means take care of inserting gas,
in particular nitrogen, inside each capsule in such a way to compensate the presence
of vacuum. Afterwards, the welding means take care of welding the aluminium sheet
onto the edge of the respective capsule. Typically, the product must be degassed before
closure of the capsule to prevent over-pressure due to the presence of the compensating
gas. Such degassing causes the loss of volatile aromatic compounds.
[0016] It is accordingly an object of the invention to provide a method for the packaging
of a beverage powder tending to evolve a gas in a capsule, in which the flavor and
aroma of the beverage powder are better preserved.
[0017] The invention is directed to a method for packaging in a capsule a beverage powder
tending to evolve a gas, according to claim 1.
[0018] This is advantageous in that it permits the packaging of a quantity of beverage powder
in a capsule after a limited degassing, a further degassing of the coffee instead
occurring within the sealed beverage capsule itself or respectively within the over-packaging
sealing-up the capsule.
[0019] According to a principle of the invention, the vacuum created within the beverage
capsule, or respectively within the over-packaging, before the capsule or respectively
the over-packaging is sealed, compensates for the pressure generated by the gases
evolved from the coffee. The accumulation of evolved gas is thus prevented from building
to a pressure that might compromise the integrity of the capsule or respectively of
the over-packaging.
[0020] Since the coffee is not significantly degassed before sealed into the beverage capsule,
the volatile aroma and flavor compounds of the beverage produced therefrom are preserved
and maintained in the capsule or respectively, in the over-packaging.
[0021] In a practical way, when the beverage powder is a ground coffee, the method comprises
a step of grinding coffee beans before the step of sealing, the duration of a degassing
step between grinding the coffee beans and sealing the cavity, or respectively, sealing
the over-packaging is less than 25 minutes, preferably less than 20 minutes, and most
preferably comprised between 5 and 15 minutes.
[0022] Thus the degassing time is reduced, and in any event, is shorter than the duration
requested in prior packaging method used to encapsulate ground coffee in a hermetically
close capsule.
[0023] According to the invention, the pressure reduction below atmospheric pressure applied
into the cavity, or respectively, into the over-packaging, in the step of applying
a vacuum, is comprised between 100 and 800 mbar, and preferably between 250 and 700
mbar, most preferably between 300 and 600 mbar.
[0024] These values are well adapted to compensate the increase of pressure in the capsule
body due to the gas evolved by the beverage powder after sealing of the capsule body.
[0025] The atmospheric pressure is the value of the pressure at the location where the step
of applying a vacuum occurs.
[0026] After the keeping step, the internal pressure is comprised between 1050 mbar and
1800 mbar, preferably between 1050 and 1600 mbar, most preferably between 1050 and
1350 mbar.
[0027] The internal pressure is stabilized to a value comprised between 1050 mbar and 1800
mbar, preferably between 1050 and 1600 mbar, most preferably between 1050 and 1350
mbar, about 72 hours after said sealing step.
[0028] This internal pressure is acceptable in term of manufacturing a sealed-up capsule
and is compatible with a 12 month shelf-life for the beverage capsules.
[0029] The description also concerns a beverage capsule comprising a capsule body defining
a cavity and being adapted to be hermetically sealed up with a quantity of beverage
powder provided within said cavity, fabricated by the method of packaging as described
above.
[0030] The beverage capsule so fabricated will embody the advantages of the method as detailed
above.
[0031] According to an advantageous embodiment of the invention, the cavity is provided
with a predetermined quantity of roast and ground coffee.
[0032] Preferably, the cavity is provided with a quantity of roast and ground coffee comprised
between 4 and 16 grams, preferably between 5 and 13 grams. At the equilibrium (after
full degassing), the cavity of the capsule has also preferably a volume between 8
to 30 ml, preferably 10 to 20 ml, most preferably 12-16 ml.
Brief Description of the Drawings
[0033] Other particularities and advantages of the invention will also emerge from the following
description.
[0034] In the accompanying drawings, given by way of non-limiting examples:
- Figure 1 is a series of orthogonal section views depicting an attachment means, a
cutting means, a vacuum-application means, and a sealing means adapted to perform
a method of packaging according to an embodiment of the invention;
- Figure 2 is a series of orthogonal views of attachment apparatuses in four different
configurations;
- Figure 3 is a flowchart depicting an embodiment of the method of packaging as integrated
into a process for the fabrication of beverage capsules; and
- Figure 4 is a schematic view of a method for packaging a capsule in a sealing over-packaging
according to an alternative embodiment of the invention.
Description of the Invention
[0035] The following description will be given with reference to the above-mentioned figures.
[0036] Figure 1 is a sequence of section views depicting the sealing of a beverage capsule
according to the invention. Figure 1 depicts the attachment and cutting steps in views
A through D, and the vacuum application and sealing steps in views E through H. Portions
of the apparatus are omitted from each of these views for purposes of clarity.
[0037] View A depicts an attachment means 100 and a cutting means 101 disposed in a first
position, prior to the start of an attachment step. The attachment means 100 and the
cutting means 101 are generally tubular and coaxial about the first longitudinal axis
102.
[0038] A capsule body 103 is positioned within the base plate 104, which is provided with
a capsule seat 105 in which the capsule body 103 is positioned. The base plate 104
is preferably configured to be mobile, facilitating a high rate of production of beverage
capsules. This mobile configuration may comprise such means as a conveyor belt system
or rotating turret, for example. In the preferred embodiment, the capsule body 103
is positioned beneath the attachment means 100 and cutting means 101 so as to be coaxial
with them about the first longitudinal axis 102.
[0039] The capsule body 103 defines a cavity 106, in which a predetermined quantity of roast
and ground coffee powder 107 is provided. The capsule body 103 is substantially cup-shaped,
and is provided with an open end 108 communicating with said cavity 106. The capsule
body 103 is further provided with a flange 109, disposed about the circumference of
the capsule body 103 at the open end 108.
[0040] The capsule body 103 is preferably fabricated from a formable material such as aluminum,
plastic, starch, cardboard, or combination thereof. Where the capsule body itself
is not gas-impermeable, a gas barrier layer may be incorporated therein to prevent
the entry of oxygen. The gas barrier may comprise a coating, film, or layer of a gas-impermeable
material such as aluminum, ethylene vinyl alcohol, polyamide, oxides of aluminum or
silicon, or combinations thereof.
[0041] For example, in one embodiment, the capsule body 103 is formed of deep-drawn aluminum.
In another embodiment, the capsule body 103 is formed of deep-drawn polypropylene
and aluminum. In a third embodiment, the capsule body 103 is thermoformed from a combination
of polypropylene, ethylene vinyl alcohol, and polyethylene terephthalate.
[0042] In a preferred embodiment, the flange 109 and the capsule seat 105 are configured
so that the capsule body 103 protrudes through the base plate 104, with the flange
109 resting directly on the base plate 104 and substantially the entire beverage capsule
103 being disposed beneath the base plate 104. In one alternate configuration, the
capsule seat may be configured as a cup, in which the capsule body is seated.
[0043] A portion of membrane material 110 is disposed between the cutting means 101 and
the base plate 104. Said membrane material 110 is preferably provided in the form
of a continuous sheet or web, which may be fed into the apparatus by techniques adapted
from those known in the art of materials handling. The membrane material 110 is preferably
flexible, permitting moderate elastic deformation. The membrane material 110 may have
a thickness between 10 and 250 microns, preferably between 30 and 100 microns.
[0044] In a preferred embodiment, the membrane material 110 comprises at least a base layer
fabricated of aluminum, polyester (e.g. PET or PLA), polyolefin(s), polyamide, starch,
paper, or any combination thereof. The base layer is preferentially formed of a laminate
comprising two or more sub-layers of these materials. The base layer may comprise
a sub-layer which acts as a gas barrier, if none of the other sub-layers are of a
material which is impermeable to gas. The gas barrier sub-layer is fabricated from
aluminum, ethylene vinyl alcohol, polyamide, oxides of aluminum or silicon, or combinations
thereof. The membrane material 110 preferably also comprises a sealant layer, e.g.
polypropylene, disposed to create a seal with the capsule body 103.
[0045] For example, in one embodiment the membrane material 110 is an aluminum layer between
25 and 40 microns. In another embodiment, the membrane material 110 comprises a base
layer with two sub-layers: an external sub-layer made of PET and an internal sub-layer
made of aluminum. The aluminum sub-layer serves the function of preventing undesirable
transmission of light, moisture, and oxygen. In another embodiment, the membrane material
110 comprises three sub-layers: an external sub-layer of PET 5 to 50 microns thick,
a middle sub-layer of aluminum 5 to 20 microns thick, and an internal sub-layer of
cast polypropylene 5 to 50 microns thick.
[0046] View B depicts the apparatus in a second position, during a cutting step. The cutting
means 101 is advanced downward along the first longitudinal axis 102 into the membrane
material 110. In a preferred embodiment, the cutting means 101 is sharpened along
its peripheral edge 111 so as to cut the membrane material 110 when pressed into it.
However, alternate configurations, such as a hot-knife apparatus, may be preferable
for certain compositions of heat-sensitive membrane material. The cutting means 101
is advanced through the membrane material 110, cutting a membrane 112 of the desired
size and shape from the membrane material 110.
[0047] View C depicts the apparatus in a third position, during an attachment step. At the
lower end 113 of the attachment means 100 are disposed a plurality of faces disposed
substantially perpendicular to the longitudinal axis 102, which are pressed into the
membrane 112. The attachment means 100 is advanced so that the lower end 113 presses
the membrane 112 into the flange 109 over a plurality of regions corresponding to
the aforementioned faces.
[0048] The attachment means 100 is configured to attach the membrane 112 to the flange 109
over the regions where the faces of the lower end 113 press said membrane 112 into
the flange 109 of the capsule body 103. In the present embodiment, the attachment
of the membrane 112 to the flange 109 of the capsule body 103 is achieved by heat-sealing;
though in other embodiments alternate techniques such as ultrasonic welding may be
preferred.
[0049] The attachment means 100 is therefore preferably furnished with appropriate means
for attaching the membrane 112 to the flange 109 during the attachment step. For example,
such means may comprise an electrical resistance heater, hot air jet, or ultrasonic
welding horn. This will make the apparatus more compact and space-efficient.
[0050] Said regions of the flange 109 corresponding to the faces of the lower end 113 of
the attachment means 100 will comprise a portion of the total surface of the flange
109. The cavity 106 of the capsule body 103 thereby remains in communication with
the surrounding atmosphere, via the spaces between the flange 109 and the membrane
112 where the membrane 112 remains unattached to the flange 109.
[0051] View D depicts the apparatus in a fourth position, after the completion of the attachment
step. The attachment means 100 and cutting means 101 are withdrawn from the capsule
body 103 and membrane 112. The scrap membrane material 110 may be removed, while the
base plate 104 is advanced in direction 114 to both place the current beverage capsule
in position for vacuum sealing and bring the next beverage capsule into position for
the attachment and cutting steps.
[0052] Preferably, the step for cutting the membrane 112 as depicted in View B and the step
for attaching said membrane 112 to the flange 109 as depicted in View C are performed
sequentially but in a continuous movement of descent of the cutting and attachment
means 101, 100. A slight vacuum is further applied through the attachment means to
maintain the membrane 112 in coaxial position in axis 102 during the cutting and attachment
steps. This is advantageous, in that it minimizes the time to fabricate a capsule
and thus increases the rate at which capsules are produced.
[0053] View E depicts the apparatus in a fifth position, prior to the start of a sealing
step. The vacuum-application means 115 and the sealing means 116 are preferably tubular
and disposed coaxially about the second longitudinal axis 117. The cutting and attachment
means depicted in the previous steps are omitted here for clarity; however, the cutting
and attachment means are ideally disposed adjacent or in close proximity to the vacuum-application
means 115 and sealing means 116, making the apparatus more compact and space-efficient.
[0054] The base plate 104 is advanced in the direction 114 until the capsule body 103 and
membrane 112 are also coaxial with the vacuum-application means 115 and the sealing
means 116 about the second longitudinal axis 117. The capsule body 103 and membrane
112 are thus positioned in a centered position directly below the vacuum-application
means 115 and sealing means 116.
[0055] View F depicts the apparatus in a sixth position, during a vacuum-application step.
The vacuum-application means 115 have been advanced so as to create an airtight seal
between the mouth 118 of the vacuum-application means 115 and the flange 109 of the
capsule body 103. A vacuum 119 is applied to the capsule body 103 through the vacuum-application
means 115, reducing the pressure in the cavity 106 of the capsule body 103 below atmospheric
pressure. The gas within the cavity 106 of the capsule body 103 is drawn out through
the plurality of spaces between the flange 109 and the membrane 112, which are defined
by the regions where said membrane 112 remains unattached to said flange 109. The
gas can be air or any inert gas such as nitrogen, CO
2 or a combination thereof. In this way, the cavity 106 of the capsule body 107 is
voided of gas without also sucking any of the coffee powder 107 from the cavity 106.
In this way, the aspiration of the coffee powder into the apparatus or its entrainment
between the flange 109 and membrane 112 is avoided.
[0056] The vacuum-application step is preferentially configured so that the vacuum may be
rapidly applied to the capsule body 103 while avoiding sucking the coffee powder 107
from the cavity 106. It is known that the rapid application of a vacuum to a beverage
capsule may cause some of the coffee powder within to be sucked out, which may result
in damage to the apparatus from aspirated coffee powder. The coffee powder may also
become entrained between the sealing surfaces of the beverage capsule, weakening the
seal and diminishing its aesthetic properties. The application of vacuum may also
cause the sealing means to move, further compromising seal integrity.
[0057] Here, the attachment of the membrane 112 to the flange 109 of the capsule body 103
over a plurality of regions will prevents the aspiration and entrainment of the coffee
powder 107 between the flange 109 and the membrane 112, as well as prevent the displacement
of the membrane relative to the capsule body during the application of the vacuum
119. The integrity of the beverage capsule seal and the reliability of the sealing
apparatus are thus preserved even when the vacuum is applied very rapidly, permitting
higher-quality beverage capsules to be produced at a faster rate.
[0058] The vacuum-application step is also preferentially configured to enable the conditions
within the capsule to be monitored as the vacuum 119 is applied. Specifically, the
vacuum-application means permits the rapid application of the vacuum 119 to a single
capsule body 103, rather than the slower application of a vacuum to a group of capsule
bodies in a vacuum chamber. Thus, by use of data collection and/or control-loop methods
known in the art, one may continually adapt the parameters of the vacuum-sealing process
to optimize the sealing of each capsule while still maintaining an overall high rate
of production.
[0059] View G depicts the apparatus in a seventh position, during a sealing step. The mouth
118 of the vacuum-application means 115 is kept in contact with the flange 109 of
the capsule body 103, such that the vacuum within the cavity 106 of the capsule body
103 is maintained. The sealing means 116 is advanced into contact with the membrane
112, pressing into it along the sealing edge 120 disposed at an end of said sealing
means 116. The membrane 112 is pressed into the flange 109 by the sealing means 116,
thereby bonding the remaining unattached regions of the membrane 112 to the surface
of the flange 109 and hermetically sealing the membrane 112 to the capsule body 103.
While the remaining unattached regions of the membrane are bonded, the bond of the
attached regions created during the attachment step may be renewed. The air-tight
hermetic seal created between the flange 109 and the membrane 112 will thereby preserve
the vacuum in the cavity 106 of the capsule body 103, protecting the coffee powder
107 from exposure to air and subsequent loss of flavor and aroma.
[0060] View H depicts the sealed beverage capsule after the completion of the sealing step.
The sealing means 116 is withdrawn to allow the bond to solidify. Then the vacuum
is stopped in the vacuum means exposing the capsule body 103 and membrane 112 to atmospheric
pressure and causing the membrane 112 to take a concave form as depicted. Finally,
the vacuum-application means 115 is withdrawn. The vacuum which was applied to the
capsule body 103 in an earlier step is preserved therein by the seal between the flange
109 and the membrane 112. The base plate 104 is then moved off in direction 114, removing
the capsule to be packaged and distributed and bringing the next capsule into position
for vacuum sealing.
[0061] Immediately after the completion of the vacuum-sealing step, the membrane 112 will
be deflected inwardly into the capsule body 103, a result of the vacuum within the
beverage capsule and exposure to the atmospheric pressure.
[0062] As a result of chemical processes triggered by the roasting process, the coffee powder
107 within the beverage capsule degasses, the gases which are evolved are kept within
the cavity 106 of the beverage capsule by the membrane 112, the capsule body 103,
and the hermetic seal between the two. This accumulation of evolved gases will cause
the pressure within the beverage capsule to increase until equilibrium pressure is
reached. At equilibrium, there will be a positive pressure within the beverage capsule,
i.e. a pressure above the atmospheric pressure, causing the membrane 112 to be deflected
outwardly.
[0063] The vacuum which is sealed into the beverage capsule thus partially offsets the pressure
generated by the gases evolved from the coffee powder 107. The degree to which the
vacuum offsets the evolved gases may vary from embodiment to embodiment, depending
on the volume of the beverage capsule, the mass of coffee provided within, and the
type and degree of roast of the coffee powder itself. In any case, the vacuum within
the beverage capsule compensates for the degassing at least to the extent that the
evolved gas is prevented from compromising the structural integrity of the beverage
capsule and its hermetic properties.
[0064] In a preferred embodiment, the pressure reduction below atmospheric pressure is comprised
between 100 and 800 mbar, preferably 250 to 700 mbar and more preferably between 300
and 600 mbar. After the beverage capsule is sealed, the gases evolved by the coffee
powder during degassing will continue to accumulate in the cavity 106 of the beverage
capsule, causing the internal pressure of the beverage capsule to rise above atmospheric
pressure in approximately 5 hours. The internal pressure of the beverage capsule will
preferably reach equilibrium between 1050 and 1800 mbar, preferably between 1050 and
1600 mbar, and most preferably between 1050 and 1350 mbar, in approximately 72 hours
after the sealing of the capsule.
[0065] Additionally, the method is preferably configured so that all, or substantially all,
of the degassing occurs within the beverage capsule after it has been sealed. While
the pressure within the beverage capsule will be negative at time of sealing, the
evolved gases will rapidly increase the pressure within the capsules. In a preferred
embodiment, the capsule will rise above atmospheric pressure in less than 5 hours
and stabilize in approximately 72 hours.
[0066] Figure 2 is a series of orthogonal views depicting a series of configurations for
the attachment means. As discussed above, the attachment means comprises at its bottom
end a plurality of faces, which are pressed into the membrane to attach it to the
flange of the capsule body over a plurality of regions corresponding to said faces.
[0067] Figure 2A depicts an attachment means provided with two faces 200 of a first kind.
The faces 200 of a first kind are separated by two channels 201 of a first kind. When
pressed into a membrane during the attachment step as described above, the membrane
will be attached to a flange of a capsule body over the portion of the surface of
the flange corresponding to the faces 200 of a first kind, while remaining unattached
and permitting fluid communication between the cavity of the capsule body and the
surrounding atmosphere. Upon the application of a vacuum, the air in the capsule body
will flow out through the unattached regions between the membrane and flange defined
by the channels 201 of a first kind.
[0068] Figure 2B depicts an attachment means provided with four faces 202 of a second kind,
separated by four channels 203 of a second kind. Such an attachment means will attach
a membrane to a flange of a capsule body over a plurality of regions corresponding
to each of the four faces 202 of a second kind, while leaving the regions of the membrane
corresponding to the four channels 203 of a second kind unattached.
[0069] Figure 2C depicts an attachment means provided with eight faces 204 of a third kind,
separated by eight channels 205 of a third kind. As above, the faces 204 of a third
kind will define the region over which a membrane is attached to the flange of a capsule
body, and the channels 205 of a third kind defining where it is unattached.
[0070] Figure 2D depicts an attachment means provided with eight faces 206 of a fourth kind,
separated by eight channels 207 of a fourth kind. Compared to the attachment means
depicted in Figure 2C, the faces 206 of a fourth kind are much smaller than the faces
204 of a third kind, while the channels 207 of a fourth kind are much larger than
the channels 205 of a third kind. As a result, the proportion of the flange of a capsule
body to which a membrane will be attached by the attachment device in Figure 2D is
much lower than would be achieved by the attachment device of Figure 2C, with a corresponding
increase in the size of the regions of the flange to which the membrane remains unattached.
[0071] The attachment devices may in this way be configured to best suit the particular
application in which the attachment device is to be employed. In the foregoing embodiments
the attachment devices are altered by adjusting their number and size; however, in
other embodiments it may be advantageous to modify other elements of their form and
geometry such as shape, thickness, or placement about the lower end of the attachment
means.
[0072] In this way, one may configure the attachment means to reduce the time required to
apply the vacuum to the capsule body while still minimizing the aspiration and entrainment
of the coffee powder or other edible granules contained within the capsule body. The
sealing of the beverage capsules may thus be optimized to achieve a maximum output
at a minimum cost.
[0073] Figure 3 is a flowchart depicting the method of packaging as integrated into a process
for the fabrication of beverage capsules, said operation comprising a series of elements.
The first step of the operation is Capsule Body Destacking 300. The empty capsule
bodies are generally stored stacked atop each other when stored before use, and so
must be separated before they can be further processed. In the step for Capsule Body
Destacking 300, the capsule bodies are separated from each other and placed in the
proper orientation to continue in the process.
[0074] Simultaneously, the Coffee Preparation Process 301 furnishes a supply of coffee powder
for packaging within the beverage capsules. In the Coffee Preparation Process 301,
coffee beans are roasted to the desired degree of roasting and then ground to the
desired degree of fineness.
[0075] As discussed above, the gases generated within the coffee beans during roasting are
evolved from the coffee. Some degassing will occur between the roasting of the coffee
and the sealing of the beverage capsule. It is preferable, however, to configure the
process for fabrication of beverage capsules to minimize degassing outside of the
capsule, so that the degassing essentially occurs after the beverage capsule has been
sealed. In an embodiment, the duration between the grinding of the coffee and the
sealing of the capsule is less than ten minutes.
[0076] By limiting degassing before sealing, the aroma and flavor in the capsule are best
preserved. After several days, equilibrium is reached between the emanated gases and
the retained gases in the coffee. This equilibrium depends on the ratio of the coffee
weight to the total volume in the capsule, the pressure reduction applied during the
vacuum step and the resistance of the capsule to the equilibrium pressure.
[0077] Furthermore, since the coffee is not degassed before the sealing process, the infrastructure
required to degas the coffee beforehand is no longer necessary. This renders the beverage
capsule sealing operation more compact, economical, and flexible.
[0078] During Product Filling & Densifying 302, a portion of the coffee powder provided
by the Coffee Preparation Process 301 is placed within the capsule body and densified,
so that the coffee is settled within the capsule body and the amount of gas therein
is so minimized. In an alternate embodiment, the beverage powder may be compacted
into a tablet during the Coffee Preparation Process 301 step, which is then positioned
in the capsule body during the step of Product Filling & Densifying 302.
[0079] Ideally, each element of the operation is linked by a step for Transport 303, where
the capsule body is transferred between the devices for carrying out each element
of the operation. In addition, it is understood that the elements for carrying out
each of the elements of the process may be located in proximity to each other, or
even integrated into each other, so that the time required for transporting the beverage
capsule between elements is minimized. The process is thereby rendered more space-efficient
and economical.
[0080] After this is Membrane Attachment and Cutting 305, as depicted in Views A-D of Figure
1. In this step, the membrane is attached to the flange of the capsule body at a plurality
of regions of the flange, leaving a plurality of unsealed regions on said flange as
well. The membrane is also cut to a size which will cover the flange and open end
of the capsule body.
[0081] Following Membrane Attachment & Cutting 305 is Vacuum Application & Sealing 306,
depicted in Figure 1, Views E-H. A vacuum is applied to the capsule body, removing
the air from within through the plurality of unsealed regions of the flange. The membrane
is then sealed over the entirety of the surface of the flange, preserving the vacuum
within the capsule.
[0082] In beverage capsules containing roasted, ground coffee as shown here, it is particularly
advantageous that the vacuum within the capsule is a reduction of pressure high enough
to offset the pressure generated by the gases evolved by the coffee as it degasses
in the capsule. A normally configured beverage capsule will so resist the pressure
accumulated within the sealed capsule as a result of the evolved gases.
[0083] Finally, the capsule is transferred to Distribution 308, where it may be packaged
in a box, sleeve, bag, or the like and distributed for sale.
[0084] Figure 4 depicts a method for packaging a capsule 400 containing beverage powder
tending to evolve a gas, in an over-packaging. The method comprises providing a quantity
of beverage powder capable of evolving a gas within a cavity 406 of a capsule body
403. The capsule body 403 is substantially cup-shaped and is provided with an open
end 408 communicating with said cavity and a bottom end 401. The bottom end may be
apertured. For example, a plurality of small apertures can be present in the wall
of the bottom end 401 to facilitate (without need for a puncturing member) the feeding
of water and/or discharge of beverage during extraction. The apertures are small enough
to allow liquid transfer but maintain powder in the cavity.
[0085] The capsule 400 may further comprise a flange 409 onto which is sealed a lid such
as a flexible membrane 412 (Step II). The membrane material is preferably provided
in the form of a continuous sheet or web. In an alternative, the lid can be a rigid
or semi-rigid wall member connected to the flange by welding, e.g., heat or ultrasonic
welding, and/or press-fitting in the cavity. The lid may be formed of a material hermetical
to gas and sealed hermetically on the flange. However, it may also be non-hermetic
to gas and liquid. For example, the lid may be apertured. A plurality of small apertures
can be present in the lid to facilitate (without need for a puncturing member) the
feeding of water and/or discharge of beverage during extraction. The apertures are
small enough to allow liquid transfer but maintain powder in the cavity.
[0086] In this embodiment, the capsule 400 is sealed in an over-packaging 500 (Step III).
The over-packaging may be a flexible or rigid package. For example, it can be a flow
wrap package sealed onto a seam 501. A vacuum is drawn before and during sealing of
the over-packaging in the interior of the over-packaging. Since the capsule 400 is
permeable to gas, a vacuum is formed in the cavity as well. A pressure equilibrium
is rapidly obtained so that the pressure in the cavity is the same as the pressure
between the capsule 400 and the over-packaging 500.
[0087] As in the previous embodiment, the gases generated within the coffee beans during
roasting are evolved from the coffee. Some degassing will occur between the roasting
and the sealing of the over-packaging. It is preferably, however, to configure the
process for fabrication of the packed beverage capsule to minimize degassing before
sealing, so that the degassing essentially occurs after the beverage capsule has been
sealed in the over-packaging (Step IV). As a result of the gas emanating in the capsule
and traversing the capsule, the pressure in the over-packaging becomes above the atmospheric
pressure. In this way the flavor of the coffee is most effectively preserved. The
over-packaging is essentially impermeable to gas so that the evolved gases after sealing
is maintained in the over-packaging. After several days, equilibrium is reached between
the emanated gases and the retained gases in the coffee. This equilibrium depends
on the ratio of the coffee weight to the total volume in the over-packaging, the pressure
reduction applied during the vacuum step and the resistance of the over-packaging
to the equilibrium pressure.
[0088] In the context as described in the above description, the hermetical closure to the
gases refers to the ability of the package, that is the capsule itself or the over-packaging,
to maintain an internal pressure above 1050 mbar for a period of at least one week.
[0089] Of course, the invention is not limited to the embodiments described above and in
the accompanying drawings. Modifications remain possible, particularly as to the construction
of the various elements or by substitution of technical equivalents, without thereby
departing from the scope of protection of the invention.
[0090] In particular, it should be understood that the present invention may be adapted
to fabricate beverage capsules for the preparation of various kinds of alimentary
substances, for example broth, cocoa, coffee, infant formula, milk, tea, tisane or
any combination thereof. It should also be understood that the edible granules comprising
said alimentary substances may be provided in various forms and sizes, such as flakes,
grains, granules, pellets, powders, or shreds and any combinations thereof. While
the particular embodiment of the preceding description is directed to a beverage capsule
containing a quantity of roasted, powdered coffee, it should not be construed as limiting
the scope of the invention to beverage capsules so configured.
[0091] The exact configuration and operation of the invention as practiced may thus vary
from the foregoing description without departing from the inventive principle described
therein. Accordingly, the scope of this disclosure is intended to be exemplary rather
than limiting, and the scope of this invention is defined by any claims that stem
at least in part from it.