Food or edible material: processes – compositions – and products – Fermentation processes – Alcoholic beverage production or treatment to result in...
Patent
1996-12-16
2000-01-25
Sherrer, Curtis E.
Food or edible material: processes, compositions, and products
Fermentation processes
Alcoholic beverage production or treatment to result in...
426 11, 426 29, 426520, C12C 720
Patent
active
060175680
DESCRIPTION:
BRIEF SUMMARY
FIELD OF THE INVENTION
This invention relates to a process for the continuous boiling of wort, as well as to a process for brewing beer from said boiled wort.
DESCRIPTION OF RELATED ART
When preparing beverages from cereals, more in particular when brewing beer, wort is used. A conventional preparation of wort occurs by mixing the starting materials, e.g., comprising unmalted grain (maize) and water. The solid materials are first pulverised and then mixed with the water. The resulting slurry is kept for some time at a temperature of at least 40.degree. C. in the presence of an enzyme source, e.g., malt. Gelatinization and liquefaction thereby occur. In a next step the enzymatic conversion of the mixture (mash) is continued after supplementary addition of malt and/or an external enzyme source. It is also possible to prepare wort on the basis of malt and water. Then the first step is omitted.
The product thus obtained consists mainly of water, insoluble components of the raw materials, as well as soluble components thereof, such as fermentable and unfermentable sugars and proteins. In the conventional method this mixture is filtered to remove the insoluble components, the spent grain. The filtrate or extract is the wort. For brewing beer, hop is then added to the wort, which is boiled. The trub formed is removed, and the wort is cooled to about 8.degree. C. and fermented.
The aim of this wort boiling operation covers a diversity of goals:
Normally the effectiveness of the boiling process is determined by three parameters: duration, intensity (e.g. evaporation) and boiling temperature.
The necessary duration of the boiling to complete all desired effects is determined by the evaporation rate and the boiling temperature. The relatively slow isomerisation of hops is the rate determining step. At atmospheric pressure and about 100.degree. C., a good isomerisation of hop takes a minimum of 45 minutes. At higher temperatures and pressures the isomerisation can be completed in times as short as two to three minutes.
Besides affecting the homogeneity of the boiling the vigour of the boiling is of special importance for the removal of volatiles. The more vigorous the boiling, the better the removal of sulphuric off-flavours. Especially sulphur compounds like dimethylsulphide (DMS) have a very low taste threshold in the final beer and can only be removed during boiling. The concentration of this compound will in fact increase again during later fermentation of the wort by yeast excretion.
The stripping effect of the boil is determined by the total evaporation during boiling and by the geometry of the wort kettle to obtain a good "rolling" boil. Typically evaporation rates of 6-8%/hr are used in the brewing industry. Because of the large amounts of water that have to be evaporated to achieve the desired off-flavour reduction, the boiling stage is one of the largest energy consuming processes in a brewery.
Although the boiling process can be accelerated significantly at elevated temperatures, either through external heat exchangers or pressure cooking or the use of multi-effect evaporators (known as HTW: High Temperature Wort-boiling), overheating of the wort is known to have undesired effects on a number of quality aspects of the final beer among which are colour and head retention.
Although this HTW process is a continuous process, with the inherent advantages thereof, this process is not acceptable because of two reasons: the range of 120-130.degree. C. which are significantly higher than what is used at the moment in the brewing industry, e.g. 100-108.degree. C. tubes of the HTW. This requires a long and intensive cleaning which does not fit the requirement of a continuous operation.
It would be advantageous if wort could be boiled continuously, as such a step could then be incorporated in a continuous wort production process. This process could for example include the process steps disclosed in U.S. Pat. Nos. 5,536,650 and 5,453,285, the contents of which is incorporated herein by way of reference.
In order to
REFERENCES:
patent: 3535116 (1970-10-01), Harsanyi
patent: 4550029 (1985-10-01), Kruger et al.
patent: 4552060 (1985-11-01), Redl et al.
patent: 4801462 (1989-01-01), Tonna
patent: 5453285 (1995-09-01), Versteegh
patent: 5536650 (1996-07-01), Versteegh
patent: 5648246 (1997-07-01), Versteegh
Kirk-Othmer Encyclopedia of Chemical Technology, 3rd Ed., vol. 9, pp. 702-03.
Brauwelt, vol. 121, 1981 Nurnberg, pp. 49-51, K. Stippler "Kontinuierliche Wurzekochung mit Warmeruckgewinnung." see p. 49, col. 3; figure 2.
Versteegh Christiaan W.
Visscher Hendrik J.
Heineken Technical Services B.V.
Sherrer Curtis E.
LandOfFree
Process for the continuous boiling of wort does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Process for the continuous boiling of wort, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Process for the continuous boiling of wort will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2314179