GB2039947A - Low carbohydrate alcohol- reduced beer - Google Patents

Abstract

In a method of producing a low- carbohydrate, alcohol-reduced and low- calorie dietetic beer a) a wort with a "root wort" content of 11-11.5% is fermented with pitching temperatures between 5 and 10 DEG C after the addition of about 2% of the original bulk of enzyme-rich grist and the addition of a greater quantity of hops than that usually employed, the fermentation temperature rising to almost 20 DEG C due to the retained fermentation heat, and the apparent degree of attenuation is allowed to reach about 100% within about eight days, b) about 2/5 to 3/5 of the total quantity is removed from the fermenter and, after mixing with 8-15% of almost boiling water, boiled without coming into contact with oxygen until the alcohol content has been reduced to 1-2 per cent by weight and water evaporated to eliminate the quantity of water added, c) after cooling the alcohol-reduced beer, this is blended with the remainder of the new beer with a low yeast content without oxygen gaining access, d) the product is filtered and racked after brief further fermentation with added fermentation carbonic acid. The amount of yeast added may be about twice the normal amount used in making beer.

Description

SPECIFICATION A method of producing a low-carbohydrate, alcoholreduced and low-calory dietetic beer The invention concerns a method of producing a low carbohydrate, alcohol-reduced and low-calory dietetic beer.

Processes for the production of beers with reduced alcohol content have been known for a long time and go back to the year 1895. German Patent 88 340 thus discloses a method of making non-alcoholic beers in which the alcoholic beer is distilled using a reflux cooler and the carbonic acid driven out in the process is replaced by artificial impregnation.

A survey of these known processes is given in "Brauwelt", 1965, page 545 to 552. This reference material also indicates that removing the alcohol by these known methods means sacrificing taste so that these known methods for producing a non-alcoholic and low-alcohol beer could not become established and did not become particularly widespread. In spite of this, there has still been no shortage of attempts to develop low-alcohol beers and dietetic beers in recent years.

German Patent 2 052 963 discloses a method for the production of a low-carbohydrate, alcoholreduced and low-calory dietetic beer which works by using different temperatures during attenuation (fermentation), adding diastase solution, removing the used and adding fresh yeast (barm) and driving off the alcohol.

This known process consists of the following operations: a) The wort is initially attenuated down toan apparent degree of attenuation of only 40 to 70% extract during a first attenuation phase at 4 to 80C, the wort exhibiting a real root wort content of 11 to 14% or, corresponding to a strong beer, 16 to 20%.

b) The attenuation is then interrupted.

c) Next the new beer is boiled until the alcohol content has been reduced to about 1%.

d) In the course of a following second phase of the main attenuation process, the new beer is taken to final attenuation. For this a temperature of between 12 and 20"C is set and then a diastase solution exhibiting a high proportion of limit dextrinases is added.

e) On completion of the second attenuation phase the new beer is cooled, and f) Then it is stored for a short time to allow the clouding substances to settle.

This known method of producing dietetic beer has a few disadvantages, particularly an inordinately long attenuation time for the two phases of the main attenuation process and in addition substantial energy consumption as is explained in detail in the following with reference to the different stages of the process.

With the known process of specific diastase solution is added twice (at the start and after the boiling operation) and hops have to be added twice when producing tbe wort and when dealcoholizing and used yeast is removed and fresh yeast added so that these steps alone entail a relatively high input of work in addition to a relatively long attenuation and storage time.

The advantage of the second hop-down saving bittern is only an apparent one because in fact the second hop boiling process also leads to some loss of bittern during "clarification" (from the yeast here).

Another disadvantage with the known process is that all the new beer is boiled until the alcohol content has been reduced to about 1%. This operation requires a considerable amount of heat since the entirety of the mixture being attenuated is brought to the boil. Experience shows that the reduction in alcohol content will take place most rapidly at the start of the boiling process while the energy input for the partial dealcoholization as the alcohol level falls is quite considerable.Further energy input is necessary to carry outthe cooling in the second phase since here again the entirety of the boiling new beer must be cooled Thus this known process is complicated in that further yeast must be added for the second attenuation phase, as indicated above, and apart from this a diastase solution enriched with a high proportion of limit dextrinase is added for the second time.

Another shortcoming of the known process lies in the fact that when boiling the beer removed in the middle of the attenuation process with a degree of attenuation of 45 to 70%, and thus containing a great deal of yeast, no fine substances and no substances to promote digestibility are introduced into the beer.

Consequently, the underlying object of the invention is to produce a low-carbohydrate, alcoholreduced and low-calory dietetic beer without impairing the other qualities of the beer, in particular its taste and digestibility, using a shortened and simplified process with extremely low energy input.

In accordance with the invention, this object is achieved in that a wort with a root wort content of 11 to 11.5% is made to ferment with pitching temperatures between 5 and 10 C following the addition of about 2% of the original bulk of enzyme-rich grist and a greater amount of hops than that usually added when making entire beer in the normal way, and the attenuation temperature gradually rises to almost 20"C (18-20 C) through the retained fermentation heat, and the beer is allowed to reach an apparent degree of attenuation of 100% within this main attenuation process lasting about eight days (between 7 and 10 days), after which a portion corresponding to about 2/5 to 3/5 of the total amount is removed from the fermenting tub and after mixing with almost boiling water in a quantity corresponding to some 8-15% of the new beer portion this is boiled in a boiling vessel without coming into contact with oxygen in the latter until the alcohol content is reduced to one or two per cent by weight while water is simultaneously evaporated to eliminate the quantity of hot water added; after cooling the alcohol-reduced new beer, this is blended with the remainder of the new beer with a low yeast content transferred from the fermenter to storage vessels in the meantime - without oxygen gaining access to give an alcohol-reduced overall product which, after relatively brief further attenuation with added fermenting carbonic acid, is filtered and racked; After this "relatively slight further attentuation" the apparent degree of attenuation in the beer has increased by 0.5 - 4%.

In accordance with the invention hops are added in a quantity greater than that usually employed when making entire beer in the normal way, preferably double the quantity.

The portion to be removed from the fermenter corresponding to some 2/5 to 3/5 of the total amount of new beer is separated from the yeast in a development of the invention so that practically no yeast goes through the boiling process. The hot water introduced into the boiling vessel is expediently supplied in a quantity matching the quantity lost during the subsequent evaporation.

Compared with the known process, the attentuation period is consistently just one week and at most nine days.

This is achieved, among other things, in that no special diastase solution is added for a second time, instead some 1-3% of the original quantity of enzyme-rich grist is added just once. In addition, there is no removal of used yeast or addition of fresh yeast; the pitching yeast is added just once at the start of the fermentation process. Lastly, there is also no need to split the fermentation process into two phases, as is the case with the named state of the art.

Given that only part of the quantity being attenuated (in fact 2/5 to 3/5 of the total volume) is brought to the boil, this means a considerable saving in heating energy compared with the state of the art.

Furthermore, a smaller energy input is required for the necessary partial dealcoholization since the boiled beer with an apparent degree of attenuation of about 100% and an alcohol content of about 4.8% by weight permits for quicker alcohol evaporation than with an apparent degree of attenuation of between 40 and 70%, corresponding to an initial alcohol content of 1.8 to 3% by weight. Thus, for the same dealcoholization effect on all the dietetic beer, roughly four times the amount of heat is needed than with the process in accordance with the invention.

Since with the process in accordance with the invention only 2/5 to 3/5 of the quantity of dietetic beer taken from the fermenter have to be cooled, this process stage also means a substantial saving in cooling energy compared with the state of the art because with the known process the entire volume of the alcohol-reduced dietetic beer has to be cooled to the attenuation temperature.

With the process in accordance with thejnvention it is particularly advantageous that in one very significant aspect a contribution is made towards the enhancement of the taste in that the introduction of boiling hot water into the boiling vessel is ended the moment the dietetic beer exhibiting an apparent degree of attentuation of about 100% is pumped into the boiling vessel. This prevents oxygen from the ambient air getting to the dietetic beer and thus impairment of the taste through oxidative action with certainty.

After the dietetic beer is boiled, it is transferred, again precluding access by oxygen (both when boiled and after cooling) directly into the unboiled portion of the dietetic beer which is by now transferred to storage vessels and is admittedly rich in carbonic acid but free of oxygen.

The "hosing operation" for the rest of the dietetic beer is carried out in accordance with the invention so that these remaining parts of the total volume of dietetic beer contain tiny amounts of both strong fermenting yeast and active malt enzymes so that the mixture of low-calory, low-alcohol dietetic beer produced when the separate portions are brought together is brought to full maturity by a brief but effective period of storage. The invention is explained in detail with reference to the following example.

Example: 1000 hl of dietetic beer wort with a rootwort content of 11.4% are cooled to 8"C and pitched with 20 hl of pasty, low-fermentation flocculating yeast (1 ml of this contains about 15 x 108 yeast cells). The sludge-free wort is transferred to the fermenter after 8 hours and left to undergo primary attenuation for one day. During this period the temperature rises to 9"C. Then 300 kg of enzyme-rich grist are added whereupon the attenuation temperature gradually rises to 20"C on its own within 48 hours and remains at this temperature for another three or four days until an apparent degree of attenuation of 100% is reached. The density of the new beer is 1.0 here).

The new beer is then cooled to about 4"C within 48 hours, through which the yeast settles at the bottom.

500 hl of new beer are pumped through a fluid meter (e.g. oval wheel meter or annular piston meter) into a wort copper fed with 80 hl of hot water; the continuous heating of the copper results in the formation of an oxygen-free inert gas layer comprising water vapour and carbonic acid above the surface of the beer. After the boiling process the meter behind the plate cooling unit shows the quantity of alcohol-reduced dietetic new beer to be exactly 500 hl. The original alcohol content of 4.8% had fallen to 1.2% by weight and the apparent extract content had risen from 0% to 1.3%.

When hosing the remainder of the new beer in the fermenter left after removing the 500 hl for boiling, this remaining quantity was found by measurement to total 425 hl and split up between three storage tanks each with a total capacity of 380 hl. Now the 500 hl of beer partially dealcoholized by boiling is also split up between these three storage tanks and then mixed thoroughly by blowing in fermenting carbonic acid for a longish time.

The mixture in these tanks is now found to be an alcohol-reduced dietetic beer which was analysed as follows Alcohol content 2.87% by weight Apparent extract content 0.73% Real extract content 1.80%

Claims (2)

1. A method of producing a low-carbohydrate, alcohol-reduced and low-calory dietetic beer using wort with a root wort content of 11 -11.5%, enzyme rich malt and boiling off the alcohol, characterised in that a) a wort with a root wort content of 11 -11.5% is brought to fermentation with pitching temperatures between 5 and 1 00C after the addition of about 2% of the original bulk of enzyme-rich grist and the addition of a greater quantity of hops than that usually employed when entire beer is made in the normal way, the fermentation temperature gradually rising to almost 20"C due to the retained fermentation heat, and the apparent degree of attenuation is allowed to reach about 100% within this main fermentation process lasting about eight days, b) then a portion corresponding to about 2/5 to 3/5 of the total quantity is removed from the fermenter and, after mixing with almost boiling water in a quantity corresponding to 8-15% of the new beer portion, this is boiled in a boiling vessel without coming into contact with oxygen in the latter until the alcohol content has been reduced to 1-2 per cent by weight while water is simultaneously evaporated to eliminate the quantity of hot water added, c) after cooling the alcohol-reduced new beer, this is blended with the remainder of the new beer with a low yeast content - transferred from the fermenter to storage vessels in the meantime - without oxygen gaining access to give an alcohol-reduced overall product.

d) which is filtered and racked after relatively brief further fermentation with added fermentation carbonic acid.

2. A method as in claim 1, characterised in that yeast is added in a quantity greater than that used normally when making entire beer, preferably double the quantity.

2. A method as in claim 1, characterised in that hops are added in quantity greater than that used normally when making entire beer, preferably double the quantity.

3. A method as in claim 1 and 2, characterised in that the portion to be taken from the fermenter corresponding to about 2/5 to 3/5 of the total quantity of new beer is separated from the yeast so that no yeast goes through the boiling process.

4. A method as in claim 1,2, and 3, characterised in that the quantity of hot water introduced into the boiling vessel just matches the quantity lost through the subsequent evaporation.

5. A method of producing a low-carbohydrate, alcohol-reduced and low calory dietetic beer substantially as hereinbefore described with reference to the Example.

6. A low carbohydrate alcohol-reduced and low calory dietetic beer when produced by the method of any preceding claim.

New claims or amendments to claims filed on Superseded claims 2 New or amended claims: