IE20100527A1 - A beer brewing process - Google Patents

Abstract

The process includes preparing a beer and storing the beer in a holding tank (12). A portion of the beer is extracted from the holding tank (12) and the pressure of this beer portion is raised to about 15 bar. Then excess nitrogen is added to the pressurised beer portion from a pressurised nitrogen storage tank (26). The pressurised beer portion with excess nitrogen is delivered through a mixer (24) to aid mixing of the nitrogen with the pressurised beer portion before return to the holding tank (12). Within the holding tank (12) the excess nitrogen then diffuses throughout the beer within the holding tank (12) to achieve a desired nitrogen content inthe beer within the holding tank (12). <Figure 2>

Description

This invention relates to a beer brewing process.

The term “beer” as used throughout this patent specification should be taken to include ale, stout, lager and the like beverages.

According to the invention there is provided a beer brewing process, including the steps of; preparing a beer and storing the beer in a holding tank, controlling the nitrogen content of the beer by extracting a portion of the beer from the tank, raising the pressure of the beer portion to a pressure in the range 12 to 15 bar, adding excess nitrogen to the pressurised beer portion. returning the pressurised beer portion with added nitrogen to the holding tank, and dispersing excess nitrogen from the pressurised beer portion throughout all the beer in the holding tank for achieving a desired nitrogen content in the beer.

In one embodiment of the invention the process includes the step of extracting a portion of between 4% and 10% of the beer from the holding tank, to which beer portion the nitrogen is added.

In a preferred embodiment, the process includes the step of extracting a beer portion of about 5% of the beer from the holding tank.

IE 1 0 0 5 2 7 -2ln a further embodiment, the process includes the step of raising the pressure of the beer portion to about 15 bar.

In another embodiment, the process includes delivering the beer portion through a re-circulating line having a pump for extracting the beer portion from the holding tank, pressurising the beer portion and delivering the pressurised beer portion through the re-circulating line back to the holding tank, a mixer in the re-circulating line downstream of the pump operable for generating turbulence to aid mixing of nitrogen with the pressurised beer portion, nitrogen being injected into the recirculating line between the pump and the mixer.

In another embodiment, the process includes the step of mixing the nitrogen with the pressurised beer portion in a mixer comprising a coil having internal baffles for generating turbulence.

In another embodiment the process includes the steps; mixing malt, barley and hot water in a mash tun at a temperature of about 20 65°C to prepare a sweet wort. delivering the sweet wort to a wort copper, adding 40% to 60% of a pre-set desired amount of hops and boiling the 25 sweet wort for between 60 and 90 minutes, adding the balance of the desired amount of hops and boiling for about ten minutes, resting the sweet wort for a pre-set time period, centrifuging the sweet wort, allowing the sweet wort to settle, 100527 IE -3delivering liquid sweet wort to a fermenting vessel, adding yeast and fermenting to form beer, and delivering the beer to the holding tank.

The invention will be more clearly understood by the following description of some embodiments thereof, given by way of example only, with reference to the accompanying drawings, in which; Fig. 1 is a schematic flow chart illustrating a beer brewing process according to the invention; and Fig.2 is a schematic illustration of a system for injecting nitrogen into the 15 beer according to the process.

Referring to the drawings, there is illustrated a beer brewing process according to the invention indicated generally by the reference numeral 1. Malt, barley and hot water are mixed in a mash tun 2 at a temperature of about 65°C for preparing a sweet wort.

The sweet wort is delivered to a wort copper 3. About 40% to 60% of a pre-set desired amount of hops is added and the sweet wort is boiled for between 60 minutes and 90 minutes depending on the type of beer being brewed. Then the balance of the desired amount of hops is added and the sweet wort is boiled for a further ten minutes.

The sweet wort is then rested for a pre-set time period prior to centrifuging 5. It is then allowed to settle 6 for 10 to 15 minutes.

Liquid sweet wort is delivered to a fermenting vessel 8. Yeast is added and the liquid is fermented to form beer. After fermenting the beer is sent to a conditioning tank 10 for about 7 days for lager and possibly up to 5 to 6 weeks for stronger beers.

IE 1 0 0 5 2 7 -4The beer is then delivered to a holding tank 12 within which it is held at a pressure of about 2 bar.

The nitrogen content of the beer is controlled by extracting a portion of the beer, typically about 5%, from the holding tank 12, raising the pressure of the beer portion to about 15 bar, adding excess nitrogen and then returning the beer portion to the holding tank 12. When returned to the holding tank 12 the pressurised beer portion containing the excess nitrogen will then release some of the nitrogen for dispersion throughout the holding tank 12 for achieving a desired nitrogen content in the beer within the holding tank 12.

Apparatus for adding the nitrogen to the beer is shown in Fig. 2. The beer is extracted from the holding tank 12 and delivered through a re-circulating line 20 back to the holding tank 12. A pump 22 in the re-circulating line 20 is operable to extract the required beer portion from the holding tank 12 and deliver the beer portion at 15 bar pressure through the re-circulating line 20 back to the holding tank 12. A mixer 24 is mounted in the re-circulating line 20 downstream of the pump 22. This mixer 24 preferably comprises a coil with baffles therein for generating turbulence to aid mixing of nitrogen with the pressurised beer portion. Nitrogen from a pressurised nitrogen storage tank 26 is injected into the re-circulating line 20 between the pump 22 and the mixer 24. It will be noted that by pressurising the beer portion extracted from the holding tank 12 excess nitrogen can be added to the beer portion which is then returned to the holding tank 12 for diffusion of the excess nitrogen throughout the remaining beer in the holding tank 12 in order to achieve a desired overall nitrogen content of the beer within the holding tank 12.

The invention is not limited to the embodiments hereinbefore described which may be varied in both construction and detail within the scope of the appended claims.

Claims (9)

1. A beer brewing process, including the steps of; preparing a beer and storing the beer in a holding tank, controlling the nitrogen content of the beer by extracting a portion of the beer from the tank, raising the pressure of the beer portion to a pressure in the range 12 to 15 bar, adding excess nitrogen to the pressurised beer portion, 15 returning the pressurised beer portion with excess nitrogen to the holding tank, and dispersing the excess nitrogen from the pressurised beer portion throughout alt the beer in the holding tank for achieving a desired nitrogen content in the beer.

2. The process as claimed in claim 1 wherein the process includes the step of extracting a beer portion of between 4% and 10% of the beer from the holding tank, to which beer portion the nitrogen is added. 25

3. The process as claimed in claim 2 wherein the process includes the step of extracting a beer portion of about 5% of the beer from the holding tank.

4. The process as claimed in any preceding claim wherein the process includes the step of raising the pressure of the beer portion to about 15 bar.

5. The process as claimed in any preceding claim wherein the process includes delivering the beer portion though a re-circulating line having a pump for extracting the beer portion from the holding tank, pressurising the beer portion and delivering the pressurised beer portion through the re-circulating line back to the holding tank, a IE 1 0 0 5 2 7 -

6. Mixer mounted in the re-circulating line downstream of the pump operable for generating turbulence to aid mixing of nitrogen with the pressurised beer portion, nitrogen being injected into the re-circulating line between the pump and the mixer. 5 6. The process as claimed in claim 5 wherein the process includes the step of mixing the nitrogen with the pressurised beer portion in a mixer comprising a coil having internal baffles for generating turbulence.

7. The beer brewing process as claimed in any preceding claim wherein the process 10 includes the steps; mixing malt, barley and hot water is a mash tun at a temperature of about 65C to prepare a sweet wort, 15 delivering the sweet wort to a wort copper adding 40% to 60% of a pre-set desired amount of hops and boiling the sweet wort for between 60 minutes and 90 minutes, 20 adding the balance of the desired amount of hops and boiling for about 10 minutes, resting the sweet wort for a pre-set time period, 25 centrifuging the sweet wort, allowing the sweet wort to settle, delivering liquid sweet wort to a fermenting vessel, adding yeast and fermenting 30 to form beer, and delivering the beer to the holding tank.

8. A beer brewing process substantially as hereinbefore described with reference to IE 1 00 527 the accompanying drawings.

9. Beer whenever manufactured according to the process as claimed in any preceding claim.