BEVERAGE CONTAINER

Abstract: A beverage container (1) for a beverage (3), which allows the beverage (3) to be dispensed to give an appearance similar to that of a beverage dispensed from draught. The container comprises a primary chamber (1) including the beverage (3), a secondary chamber (2, 21) including fluid, and a duckbill valve (4) arranged so that the fluid contained in the secondary chamber (2, 21) is jetted into the beverage (3) in the primary chamber (1) via the duckbill valve (4) upon opening of the container (1).

Description: BEVERAGE CONTAINER BACKGROUND OF THE INVENTION This invention relates to a beverage container for a carbonated beverage which enables a close-knit creamy head to be formed on the beverage as it is dispensed so that it has an appearance similar to that of a beverage dispensed from draught. Such an appearance can be achieved by causing shear of the beverage. This encourages the liberation of small bubbles from the beverage and these gradually separate out to form the close-knit creamy head. It is well known that shear of the beverage can be caused by jetting fluid into the beverage in the container. DESCRIPTION OF PRIOR ART Various methods have been disclosed for jetting fluid into a beverage in a container upon opening of the container to cause shear of the beverage. GB-A-1,266,351 discloses a container which includes an inner secondary chamber which is pressurised with gas. The chamber is initially sealed with a soluble plug which dissolves shortly after filling the container with beverage, when the pressure in the container is similar to that in the secondary chamber. A small orifice is included in the secondary chamber, and fluid is jetted from the secondary chamber via the orifice into the main body of the container causing the liberation of the required small bubbles in the beverage. GB-A-2,183,592 discloses a container including a separate hollow insert having an orifice in its side wall. As the container is filled, beverage is introduced into the hollow insert through the orifice. Upon opening the container, beverage from the insert is jetted through the orifice into the beverage in the container again causing shear of the beverage. Our earlier specification O-A-91/07326 discloses a container with a hollow insert which includes a means responsive to the opening of the container to provide communication between the inside of the insert and the beverage in the body of the container. Examples of the means responsive to the opening of the container includes a burst disc and a pressure responsive valve. Fluid in the insert is jetted into the beverage in the container when there is communication between the inside of the insert and the container. SUMMARY OF THE INVENTION According to the present invention, a container comprises a primary chamber including a beverage, a secondary chamber including fluid, and a duckbill valve arranged so that the fluid contained in the secondary chamber is jetted into the beverage in the primary chamber via the duckbill valve upon opening of the container. The use of a duckbill valve through which fluid is jetted is particularly beneficial. The size of the aperture through which the fluid is jetted varies with the pressure difference across the valve and the nature of the fluid being etted. This variation in the size of the aperture ensures the fluid jetting into the beverage causes optimum shear. This allows the volume of fluid required for jetting into the beverage to be reduced when compared to the volume required when jetting through a fixed size orifice. The secondary chamber may contain a mixture of beverage and gas, or merely beverage or gas. When the chamber contains only gas, the variation in the size of the aperture of the duckbill valve with pressure ensures the gas is jetted at a substantially constant velocity. Preferably the secondary chamber is a separate hollow insert which may be fixed in the primary chamber, or may float on the surface of the beverage. In this case, the insert may be closed with the exception of the duckbill valve, however the insert preferably allows fluid to enter to pressurise the insert. This means that the insert need not be pre-pressurised. Fluid may enter the insert through a gas permeable membrane, or through a second one-way valve. Alternatively, the insert may have a permanent orifice through which fluid from the primary chamber enters the insert. Instead of a separate insert, the secondary chamber may be defined by a divider which separates the container into two chambers. This may be achieved by a plate across the container. The duckbill valve is preferably manufactured form a thermoplastics material, for example a styrene-ethylene- butylene-styrene block co-polymer. This is inexpensive. The valve has a pair of opposed lips extending from a normally closed end to an open end adjacent a body of the valve. Preferably a flange is provided around the valve body, and an annular rib is provided on the body of the valve adjacent the open end of the lips. Preferably, the valve is mounted in a hole in the wall of the secondary chamber. The hole is preferably of a slightly smaller diameter than the body of the valve. In this case, it is advantageous for the valve to include the flange and annular rib so that the valve may be pushed into the hole with the flange on the inside of the chamber, and the annular rib on the outside of the chamber, with the wall of the chamber gripping the intermediate body portion of the valve. BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 shows in cross-section an example of a container according to the present invention; Figure 2 shows a sectioned perspective view of an alternative example of an insert for use in a container according to the present invention; Figure 3 shows in cross-section a first example of °- duckbill valve suitable for use in a container according to the present invention; Figure 4 shows in cross section a second example of a duckbill valve suitable for use in a container according to the present invention; and, Figure 5 is a graph showing the pressure in an insert after opening a container. DESCRIPTION OF PREFERRED EXAMPLE Figure 1 shows a container 1 including a separate hollow insert 2 and a beverage 3. The hollow insert 2 has a normally closed duckbill valve 4 which is below the surface of the beverage 3. As shown more clearly in Figure 3, the duckbill valve 4 has two opposed valve lips 10, 11. The lips 10, 11 are slightly curved. The lips 10, 11 are connected to the body of the valve which includes a flange 12 and an annular rib 14 separated by an intermediate portion 13. The valve 4 is made from a thermoplastics material, for example a styrene- ethylene-butylene-styrene block copolymer. The valve 4 allows fluid to flow from the flange end through the normally closed end of the lips by forcing the lips 10, 11 apart. Fluid is prevented from flowing in the reverse direction as the lips 10, 11 are forced together. The valve 4 is mounted in a hole in a wall of the insert 2. The hole has a diameter slightly smaller than the outer diameter of the intermediate portion 13. The shape of the annular rib 14 allows the valve 4 to be pushed into the hole so that the annular rib 14 is on the outside of the insert 2, and the flange 12 is on the inside of the insert 2. The sidewalls of the hole in the insert 2 bite into the intermediate portion 13 of the valve 4 creating a seal. The annular rib 14 is shaped to ensure that the valve 4 cannot easily be removed from the hole after insertion. In a second example of a duckbill valve as shown in Figure 4, the annular rib is omitted. This makes it easier to mount the valve, and relies solely on the biting of the side walls into the intermediate portion to hold the valve in place. The insert 2 is charged to a super-atmospheric pressure, and is sealed in the container 1. The sealed container 1 is also at a super-atmospheric pressure similar to that in the insert 2. Upon opening the container 1, the pressure in the container 1 vents to atmospheric pressure, creating a pressure difference between the inside and outside of the insert 2. Accordingly, fluid is jetted into the beverage 3 from the insert 2 via the duckbill valve 4. Initially, the pressure difference between the insert 2 and container 1 will be high, and therefore the lips 10, 11 of the valve will be forced open to give a large aperture through which the fluid jets. As shown in Figure 4, the pressure difference quickly reduces, therefore the force opening the lips 10, 11 reduces and accordingly the aperture through which the fluid jets reduces. This ensures the velocity of the jet of fluid remains constant for a longer period than when jetted through a simple orifice. Accordingly, the volume of fluid needed to give the required jetting velocity for the required duration to shear the beverage is smaller than is necessary where the fluid is jetted through a simple orifice. Rather than pre-pressurize the insert 2, which would require the insert to remain in a high pressure environment prior to packaging to prevent premature venting through the valve, other means can be used to build up a super- atmospheric pressure, for example providing a gas permeable membrane which allows gas from the beverage to enter the insert, or a deformable insert which contracts to reduce its internal volume, thereby increasing the internal pressure. Instead of having a separate hollow insert, the container may be divided into a primary and secondary chamber by including a dividing wall across the container. Figure 2 shows a further example of an insert 21. The insert 21 is made from lacquered aluminium and is designed for use in an aluminium container to facilitate recycling. The insert 21 has a circular base 22. The base 22 has a thickness of between 0.5 and 1mm. The sides and top 23 of the insert 21 are integrally formed in an inverted cup shape from aluminium of 0.2mm thickness. The thicker aluminium of the base 22 means that the insert 21 floats with the base 22 lowermost. A first one-way valve 26 is mounted in the top of the insert, and a second one¬ way valve 4 is mounted in the base 22. The side walls are flanged outwardly towards the bottom for receiving the base 22, and the edge 24 is rolled over to hold the base 22 in position. The base 22 has an indented annular portion 28, which is arranged towards the outside of the base 22. This is used to centre the base 22 with respect to the side walls of the insert 21. A sealing material 25 such as a foamed can seal lining compound is used to seal the side walls and base. This has two functions. Firstly, the compound seals the base 22 against the rolled end 24 of the side walls, thereby sealing and retaining the base 22 in position. Secondly, the compound 25 covers the cut edges of the base 22 and the side walls. This protects the cut edges, and prevents these from corroding, which would otherwise impair the taste of the beverage. Both the one-way valves 26, 4 are TPE duckbill valves. The holes for the valves 26, 4 are of a slightly smaller diameter than the diameter of the tubular body portion of the duckbill valves 26, 4, so that the edges of the hole bite into the valve 26, 4. This helps retain the valve 26, 4, and prevents the cut edges of the insert 21 from being exposed to the beverage and corroded. The valves 26, 4 include an annular rib and a flange, which are positioned on either side of the hole to retain the valves 26, 4. The internal volume of the insert 21 depends upon the beverage contained in the container, but is typically between 2 ml and 7 ml. When filling the container, the insert 21 is dropped into the container, and the container and insert 21 are together flushed with inert gas to remove any oxygen from the inside of both container and insert 21. The ccontainer is then filled with carbonated beverage, dosed with liquid nitrogen, and sealed. After sealing the container, the contents are heated to pasteurise the beverage. During heating, the pressure in the container increases. The increase in pressure causes the first one-way valve 26 to open and gas from the headspace to enter the insert 21. The internal pressure of the insert 21 does not exceed the internal pressure of the container, so the second one-way valve 4 remains closed. After pasteurisation, the beverage cools and the internal pressure of the container decreases. The internal pressure of the insert 21 then exceeds the internal pressure of the container, and the second one-way valve 4 opens allowing gas from the insert 21 to be ejected into the beverage. In this way, the internal pressure of the container and the insert 21 remain in equilibrium. Upon opening of the container, the internal pressure of the container rapidly vents to atmospheric pressure. At this time, the internal pressure of the insert 21 is higher than that of the container, and accordingly gas from the insert 21 is jetted into the beverage via the second duckbill valve 4. The jet of gas causes shear in the beverage with a resulting liberation of a number of small bubbles which, as they rise through the beverage in the container, form nucleation sites which trigger the liberation of further small bubbles throughout the beverage. As the beverage is poured out of the container and into a receptacle such as a drinking glass the bubbles from the top surface of the beverage are intimately mixed with the remainder of the beverage as it is dispensed. This triggers the release of further small bubbles throughout the beverage to give the appearance of dispensing the beverage from draught.

Claims: C L A I M S 1. A beverage container (1) comprising a primary chamber (1) including a beverage (3), a secondary chamber (2, 21) including fluid, and a duckbill valve (4) arranged so that the fluid contained in the secondary chamber (2, 21) is jetted into the beverage (3) in the primary chamber (1) via the duckbill valve (4) upon opening of the container (1) . 2. A beverage container (1) according to claim 1, in which the secondary chamber (2, 21) contains only gas, and the variation in the size of the aperture of the duckbill valve (4) with pressure ensures the gas is jetted at a substantially constant velocity. 3. A beverage container (1) according to either claim l or 2, in which the secondary chamber (2, 21) contains liquid. 4. A beverage container (1) according to any one of the preceding claims, in which the secondary chamber (2, 21) is a separate hollow insert which is fixed in the primary chamber. 5. A beverage container (1) according to any one of claims l to 3, in which the secondary chamber (2, 21) is a separate hollow insert arranged to float on the surface of the beverage. 6. A beverage container (1) according to any one of the preceding claims, in which the secondary chamber (2, 21) includes a means to allow fluid to enter to pressurise the secondary chamber (2, 21). 7. A beverage container (1) according to any one of the preceding claims, in which the duckbill valve (4) is manufactured from a thermoplastics material, for example a styrene-ethylene-butylene-styrene block co-polymer. 8. A beverage container (1) according to any one of the preceding claims, in which the valve (4) has a pair of opposed lips (10, 11) extending from a normally closed end to an open end adjacent a body of the valve (4) , a flange (12) provided around the valve body (4) , and an annular rib (14) provided on the body of the valve (4) adjacent the open end of the lips (10, 11) . 9. A beverage container (1) according to claim 8, in which the valve (4) is mounted in a hole in the wall of the secondary chamber (2, 21). 10. A beverage container (1) according to claim 9, in which the hole in the wall of the secondary chamber (2, 21) is of a slightly smaller diameter than the body of the valve (4) , and the valve (4) is pushed into the hole so that the flange (12) is on the inside of the chamber (2) , and the annular rib (14) is on the outside of the chamber with the wall of the chamber (2) gripping at an intermediate body portion (13) of the valve (4) . 11. A beverage container (1) according to any one of the preceding claims, in which the secondary chamber (21) including a second one-way valve (26) arranged to allow gas to enter and pressurise the secondary chamber (21) .

Inventors: ROSENS ERWIN ANTON, SILLINCE MARK ERICH, ROSENS, ERWIN, ANTON, SILLINCE, MARK, ERICH
Applicants: HEINEKEN TECH SERVICES, ROSENS ERWIN ANTON, SILLINCE MARK ERICH, WHITBREAD & CO LTD, HEINEKEN TECHNICAL SERVICES B.V., ROSENS, ERWIN, ANTON, SILLINCE, MARK, ERICH, WHITBREAD PLC
Application year: 1995
Main classification: B65D79
IPC codes: B65D8, B65D25, B65D79, B65D81, B65D83, B65D85