American Handy Book of the Brewing, Malting, and Auxiliary Trades/Production of Thick Mash Beers in Germany and Austria
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This article represents a section of the classic public domain brewing text "American Handy Book of the Brewing, Malting, and Auxiliary Trades" by Robert Wahl and Max Henius. See the main entry on this book for general information and a complete table of contents. | 
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[edit] Production of Thick Mash Beers in Germany and Austria
The data on this subject were mainly taken from Thausing's "Malzbereitung und Bierfabrikation," 1898.
Contents |
[edit] Properties of thick mash beers.
(See also "Malting in Germany.")
Bavarian beer is light-brown (like the Munich) to dark-brown (like the Kulmbacher). It has palate-fulness, a sweet taste and malt flavor. Balling of wort about 12.5 to 14.5, Export and Bock about 15 to 18. On account of the pronounced malt taste the beer should be but lightly hopped.
Bohemian beer (like the Pilsener) is light-yellow to greenish-yellow, the taste is vinous, dry, somewhat sharp; instead of the malt taste, the bitter taste of hops predominates. The light Bohemian "Abzug," or "Schenk" beers arc brewed 10.5 to 11.5 Balling, and are racked either in a clear condition or krausened (Hefenbier). The lager beers, usually from worts of 12.5 per cent, are as a rule not krausened.
Wiener beer as to taste, amount of hops and color takes a middle place between the other two.
The lager beer is brewed 13.5 Balling, the "Abzug" beer, which is racked soon after fermented, about 10.5. Wiener "Marzen" and export beers about 14.5 to 15.5 Balling.
[edit] The decoction or thick mash method.
According to Thausing modern beer in Germany and Austria is brewed according to the decoction method with three mashes, while formerly three different systems were distinguished and known as the Vienna, the Bavarian and the Bohemian. This distinction has become obsolete, since at present in Austria, especially in Vienna, as well as in Bohemia and Germany the decoction method with three mashes is universally employed. Here and there slight changes are made in certain breweries in regard to the temperature periods and the time of boiling the mash without, however, any perceptible differences in results as to the character of the beer.
The initial or duughing-in temperature is about 28° to 30° R. (95° to 100° F.). If hot water is run in, it should be done slowly and while keeping the mashing machine moving, so that this proceeding will take 15 to 20 minutes.
Three parts of the whole mash are successively boiled and called the first, second and third mash, each for 10 to 45 minutes. In Bohemia, where pale beers are the vogue, boiling is often restricted to 10, 15 or 20 minutes, in Vienna generally 30 minutes, in Bavaria often 45 minutes.
As to heating the mash in the kettle, experience shows that this should not be done too quickly, but that on the other hand, it is not only a waste of time, but also may impair the quality of the beer, if the mash is left for a prolonged period at low temperature, i. e., heating it too slowly. This heating is governed to a certain extent by the qualities of the malt. The method of heating is most important with the first mash, which, in the three-mash process, is run into the mash kettle at a temperature of 28° to 30° R. (95° to 100° F.), and there frequently raised to 40° to 45° R. (122° to 133° F.) by the remaining water.
This thick mash is then raised in 20 to 30 minutes to 60° R. (167° F.) and in 10 to 15 minutes more to a boil. To prevent scorching, the stirrers must be kept going until boiling begins. Where imperfect stirring devices are in use the temperature is not uniform throughout the mash, but higher at the bottom and near the sides than is indicated by the thermometer in the mash.
Enough of the thick mash was run into the pan to bring the total mash in the mash tun (first mash) to 40° to 42° R. (12.2° to 126.5° F.) by pumping it over. The mash should be pumped neither too fast nor too slowly. What is said about heating the mash applies here as well. About 15 minutes may be taken for this work.
The mash having been well worked through, a sufficient quantity is again run into the mash kettle so as to bring, upon return, the total (second) mash to 50° to 52° R. (144.5° to 149° F.). Part of the first mash having remained in the pan the second mash generally has 50° to 55° R. (i44-5° to 156° F.) at once upon reaching it and can be so heated that it comes to a boil in 15 to 25 minutes, according to the malt.
The first two mashes are thick mashes. By keeping the mash machine going while the mash runs into the pans, much of the thick part of the mash passes into the pans. Brewers formerly were particular to boil very thick mashes, thinking thereby to make the beer very full to the palate. The third mash is generally a "lauter" or thin mash. Before running it from the tun the mash is allowed to rest for a while, permitting the solid parts to settle to some extent, whereupon the mash is run off so as to get as much clear mash as possible into the kettle. Brewers used to put a strainer before the outlet and, in some brew-houses, to drain off the "lauter" mash through the false bottom. At present, the distinction between thick and "lauter" mashes is not often made, and frequently three thick mashes are purposely boiled.
The third mash is brought to a boil as quickly as possible, usually in about 15 minutes. The quantity is to be taken so that the main mash reaches 60° R. (167° F.) by pumping up the "lauter" mash from the pan. This last operation is called "final mashing." It is followed by pumping the mash into the strainer (Lauterbottich), where it is kept in motion for some time by crutches or stirring machine to enable the grains to settle uniformly.
The decrease of diastatic power in the decoction mashes according to Lintner is considerable. (Zeitschrift f. d. ges. Brauwesen, 1888, p. 317.) If this power at 28° R. is designated as 100, it was found to be 61.1 at 42° R., 26.8 at 49.8° R., and only 26.8 during the straining period.
The mash having been brought from the mash-tun to the strainer (Lauterbottich) is left to stand. Then the wort is strained and the grains sparged, using the same general precautions already described for the respective processes in the production of American lager beers.
The wort is generally boiled in the kettle until it shows a good "break," then one-half of the hops is added, and after one hour's boiling the second half, which is boiled for an hour to an hour and one-half more. Total length of boiling with hops, two to two and one-half hours. Sometimes one-half of the hops is added as soon as the wort boils, one-quarter after one hour, the last quarter one hour before running out.
According to Thausing (Malzbereitung u. Bierfabr., 1898, p. 609) the amount of hops used for the different types of beer is generally given per hectoliter (about 25 gals.) of wort, mentioning the saccharometer indication of the wort.
For Bavarian beer, to one hectoliter beer of 12.5 to 14.5 per cent, hops to the amount of 0.20, 0.28 to 0.30 kg. are used.
For Vienna beers the quantities of hops per hectoliter used are as follows (1 kilo = 2.2 pounds):
| For 10.5 per cent sacch. indication | 0.20 — 0.22 — 0.26 kg. |
| For 11.5 per cent sacch. indication | 0.25 — 0.28 — 0.30 kg. |
| For 12.5 per cent sacch. indication | 0.30 — 0.33 — 0.36 kg. |
| For 13.5 per cent sacch. indication | 0.32 — 0.36 — 0.40 kg. |
| For 14.5 per cent sacch. indication | 0.38 — 0.40 — 0.42 kg. |
| For 15.5 per cent sacch. indication | 0.40 — 0.45 — 0.50 kg. |
For Bohemian beer the quantities of hops per hectoliter are as follows:
| For 10.5 per cent sacch. indication | 0.30 — 0.35 — 0.40 kg. |
| For 11.5 per cent sacch. indication | 0.35 — 0.40 — 0.43 kg. |
| For 12.5 per cent sacch. indication | 0.42 — 0.46 — 0.50 kg. |
| For 13.5 per cent sacch. indication | 0.45 — 0.48 — 0.55 kg. |
The boiling of the wort in the kettle, as well as the mashing in the mash pan, is as a rule still accomplished by means of direct firing, but steam heating is more and more taking its place in breweries of modern construction, since brewers have become convinced that the claims as to superior quality of beer from fire-boiled worts rested on prejudice. The amount of coal needed in steam heating compared to fire heating for the boiling of mashes and wort is about two to three. The amount of steam, according to Thausing, needed for this work, based on actual tests, varied from 36 to 54 kg. per hectoliter wort, which, based on an evaporating effect of 7.5 kg. would mean 4.8 to 7.2 kg. of coal per hectoliter, or about 13 to 20 pounds per American barrel, which figure is to be increased by 50 per cent in case of heating by direct fire.
In cooling the wort the same methods are employed and the same precautions are to be observed as in the corresponding operations in America (which see).
According to Prior, German worts contain in 100 pans of wort extract the following constituents, in approximate quantities:
| Saccharose | 2 to 6 per cent |
| Dextrose and levulose | 6 to 9 per cent |
| Maltose | 52 to 63 per cent |
| Dextrins | 18 to 26 per cent |
| Gums (taken from the amount of gum obtained by Lintner from a Munich beer), about | 0.18 per cent |
| Nitrogenous substances (N X 6.25) | 3.13 to 5.6 per cent |
| Mineral substances, about | 2 per cent |
| Free acids calculated as lactic acid | 0.6 to 0.9 per cent |
Aubry gives results of boiling hops with wort with regard to the amount of albuminoids eliminated. In 100 parts of wort extract he found the following amounts of nitrogen for unboiled wort and after boiling with hops (Wagner's Jahresberichte. 1892, P. 845):
| Total Nitrogen. | Nitrogen not precipitable by phospboro-tungstic acid. | Amido Nitrogen. | ||
|---|---|---|---|---|
| Unhopped wort | A | 0.9263 | 0.5700 | 0.4053 |
| B | 0.7915 | 0.5458 | 0.3845 | |
| C | 0.7653 | 0.5518 | 0.3967 | |
| Hopped wort | A | 0.8921 | 0.7114 | 0.5943 |
| B | 0.7576 | 0.4765 | 0.2964 | |
| C | 0.7416 | 0.5106 | 0.3881 |
Bungener and Fries obtained amounts of different albuminoids before and after boiling, as follows:
| Before boiling. | After boiling. | |
|---|---|---|
| Total nitrogen | 0.650 per cent | 0.540 per cent |
| Albumen nitrogen | 0.163 per cent | 0.O57 per cent |
| Peptone nitrogen | 0.125 per cent | 0.100 per cent |
| Amide nitrogen | 0.362 per cent | 0.383 per cent |
[edit] Practice of fermentation in Germany.
According to Thausing, the pitching temperature is chosen lower for light colored beers and higher for dark colored ones, generally between 4° and 6° R. (41° and 45.5° F.). The maximum temperature of fermentation for Bohemian beers is 6° to 7° R (45.5° to 47.75° F.), for Vienna 7° to 7.5° R. (47.75° to 49° F.), for Bavarian 8° and 8.5° R. (50° to 51° F.). The amount of yeast used is the greater, the higher is the Balling indication of the wort, the smaller the fermenting vats, and the lower the temperature. The amount generally varies from one-third to three-fourths liter and should never be less than one-half liter for hectoliter of wort (about one pound per barrel).
The temperature of the beer after fermentation at the time when it is ripe for casking is 5° to 6° R. (43° to 45.5° F.). Sometimes it is cooled in the fermenting vats to 2° to 3° R. (36.5° to 38.75° F.). In the Munich breweries the beer is cooled on the way from the fermenting vat to the storage cellars, by means of pipe coolers to 3°, 2° or 1.5° R. (38.75°, 36.50° or 35° F.). The beer, ripe for casking, should contain a sufficient quantity of fermentable extract so that the secondary fermentation may proceed properly in the storage cellar. The opinion that high attenuated beers have a low degree of palate-fullness, and low attenuated beers a high degree thereof is untenable. If the beer in the fermenting cellar has high attenuation and shows sluggish after-fermentation a light bodied beer with poor foam-holding capacity is the result, whereas a high attenuation in the fermenting cellar combined with a proper secondary fermentation is unobjectionable. It is to be considered a favorable symptom if the difference between the attenuation of principal and secondary fermentation is a large one, and unfavorable if the difference is small. It will be unsatisfactory if this difference is only 2 to 5 per cent, satisfactory if 10 to 15 per cent, while differences of 20 per cent have been observed.
Some illustrations may be given:
1. A wort showing 10.5 per cent by the saccharometer reached 3.5 per cent by the saccharometer in the fermenting cellar, i. e., 66.6 apparent degree of attenuation (v = 66.6 per cent). After remaining in storage for six weeks the saccharometer still showed 3.2 per cent. The apparent degree of fermentation of the beer is calculated at 69.5 per cent (v' = 69.5 per cent). The difference between fermentation in fermenting and storage cellar (v' — v) is 2.9 per cent. The beer will turn out unsatisfactory.
2. A wort showing 13.5 per cent by the saccharometer is fermented in the fermenting cellar to 5.5 per cent (v = 59.2 per cent); in the storage cellar after four months to 4 per cent by the saccharometer (v' = 70 per cent). v' — v = 10.8 per cent. The fermentation is normal.
3. A wort is fermented in the fermenting cellar from 10.5 per cent by the saccharometer to 3.5 per cent, and in the storage cellar to 2.5 per cent by the saccharometer. v = 66.6 per cent, v' = 76.2 per cent; v' — v = 9.6 per cent. Notwithstanding the high apparent attenuation in the fermenting cellar the beer may be faultless.
The degree of attenuation that is desirable is different for different types of beer. For Bavarian beers an apparent degree of fermentation of 50 per cent is sufficient, whereas for Vienna and Bohemian beers 55 to 60 per cent is desired. Beers with low original extract should not attenuate so highly as beers with a high original extract.
[edit] Chip and storage cellar.
Bohemian and Wiener lager beer is treated quite similarly in storage. Both are run "lauter" from fermenter, not "green;" storage temperature should be low, after-fermentation slow. The 12 per cent Bohemian lager beer is stored three to four months, the Wiener 13 per cent lager beers, about four to five months; neither is krausened; the Bohemian is bunged for a long period, the Wiener often is not bunged at all.
Wiener "Abzug" beer, for which cold storage is essential, is fix to eight weeks old, and is racked after a short bunging period. The Bohemian "Jungbier" is usually krausened when racked into the trade packages and must consequently be allowed to settle before tapping.
Bavarian beer is not aged as much as the others as this would interfere with the sweet taste and palate-fulness. Bavarian beer is brought on the market after bunging about eight to fourteen days, about four to ten weeks old. the stronger beers being stored longer.
In piping beer the casks can never be filled to the bung-hole, owing to the foam. Hence, they must be filled up the following day. Sooner or later a white foam appears at the bung-hole, which proves an active secondary fermentation. The greener the beer was racked into cask, the more it contains of readily fermentable extract, and the warmer the beer and the storage cellar are kept, the bigger will be the hood of foam, and the after-fermentation may be so vigorous that beer is ejected from the bung-hole and runs down over the cask. This ought not to happen. In order to avoid loss of beer and for the sake of cleanliness, vessels are placed on the bung-holes to receive the foam and beer that is forced out, which is always very bitter. This is used for filling up casks or, properly treated, can be put on the market. The same object can be attained by not filling up the casks to the bung-hole until the intensity of secondary fermentation has somewhat abated. It is always advisable to let the foam work out of the bung-hole.
If no hood of foam rises from the bung-hole, notwithstanding the casks are full, or if it disappears very soon after rising, the beer being "dead" in the cask, it is a sign of deficient secondary fermentation which is always bad. The causes may be faulty malt, either overgrown or undergrown or spoiled in kiln, yielding a deficiency of fermentable extract in the beer; more rarely it may be due to casking the beer while too "lauter" (clear). The brewer should always watch the secondary fermentation closely.
The hood of foam contracts and takes on a deeper color, finally disappearing entirely, which is always the case with a sound beer if the cask was not full. The composition of the extract, the strength of the beer and the temperature of the cellar cause the foaming to stop sooner or later. What the brewer wants is that the hood remain for rather a long time without any violent working out. It affords a symptom for judging the progress of the secondary fermentation. After the hood has disappeared, the cask is filled up once more. For beers that are used young, stored cold, and properly prepared so as to be of normal composition, it ought to be enough to fill up once, as the secondary fermentation lasts a long time. Lager beers are generally filled up two or three times and when they have stopped throwing up foam, the bung-hole is loosely covered with the wooden bung.
[edit] Clarifying chips.
While in storage, a sound beer becomes clearer by degrees, the particles making it turbid, as yeast and other suspended matters, especially albuminoids, settling on the bottom. In order to hasten clarification and make it perfect, clarifying chips are put into the beer where filters are not used. These chips are made of hazel or white beechwood. The wood is cut so as to secure straight chips about 16 to 18 inches long, 1.5 to 2 inches wide, and 1/16 to 1/10 inch thick. They should be smooth and without cracks. Before using them they are thoroughly boiled in a special tub, changing the water repeatedly, steam that is pure and without oil or other impurities being commonly used, whereupon they are rinsed in cold water. They are wet when put into the storage cask, being inserted either into the empty cask through the manhole, which is simple and quick, or being added through the bunghole after the cask has been filled with beer. The beer is run on the chips if it is to be marketed soon, whereas it is preferable to insert the chips through the bung-hole if the beer is to remain on storage for some time. They can be put in two to four weeks before racking for shipment, in the latter case. As to the number of chips for a cask a little experience will speedily give the requisite information. The more quickly the beer is to be clarified and the more stubborn it is of clarification the more chips should be used. As a rule one kilogram of wet chips is enough for one hectoliter of beer, which is equal to about half a kilogram of dry chips. Care should be taken to prevent chips lying in front of the tap-hole, which might cause trouble in racking. This is more likely to happen where the beer is run on the chips and for that reason experienced brewers generally prefer to put in the chips through the bung-hole or else remove the chips from the tap-hole after the cask has been filled.
[edit] "Kraeusening."
Occasionally the practice is met with of pumping beer intended for local consumption, from the storage cask to smaller casks, often on chips, and to "krausen" it strongly at the same time, whereupon after it has become clear, it is bunged and racked, or, in small breweries, drawn directly for immediate consumption. It is believed to acquire particular brilliancy and life by this treatment.
Lager beers, and often young beers, are generally racked from the storage casks without "Krausen" and quite clear. They are called "Abzugbier" in Austria. In Bohemia more especially, the practice prevails of adding some fermenting wort, in the low "Krausen" stage, to clear young beer when racking into trade casks, particularly in the cold season. This wort is called "Krausen" for short. The amount of "Krausen" to be added should be the greater, the less active is the yeast, the older and more attenuated the beer, the more foam is desired, the warmer the storage cellar in the brewery and the colder the bar-room in which it is to be kept while being consumed. The amount of "Krausen" should, therefore, be governed by the condition of the beer and yeast, and the season. If too much is added, there will be danger of the beer being turbid when tapped and perhaps not becoming clear again at all. A small amount of "Krausen" is half a liter per hectoliter, a large amount is 5 to 6 liters. As a rule, 2 to 4 liters per hectoliter is enough. The amounts must be determined empirically in each brewery and varied to meet the requirements.
"Krausen" should always be taken from normally fermenting worts.
"Krausened" beer, before being drawn, should lie still in the place of consumption for some time, from one to eight weeks, according to the temperature of the place. It should also remain lying still while being drawn. Only in rare cases does the practice survive of the dispenser of the beer opening the cask, filling it up until it is clear, and bunging it once more. If this is done, plenty of "Krausen" should be given, as much as 10 liters per hectoliter or still more.
"Krausening" serves to revive active fermentation in the beer. It is made to foam strongly and the large amounts of carbonic acid developed imparts a sharp taste and the foam becomes firm. It enables even beers that have been stored warm and are not suitable for consumption, as "Abzug" beers, to be sold in good condition. This affords a reason why breweries which put out "krausened" beer need not be so particular about keeping their cellars cold. The Bohemian breweries sell their young beer all through the year almost altogether with "Krausen," only lager beer being marketed without "Krausen." It is the practice at Pilsen to allow the beer after being racked into trade casks with "Krausen," to lie in the brewery for several days and undergo another fermentation, filling them up again just before they leave the brewery. The beer thereby becomes ready for consumption in the dispenser's room in a shorter time, requiring less time of storage on that account, furthermore, being stored in a cold cellar will foam better, the foam will be more solid and lasting, and the beer taste more prickly, all of which are virtues that distinguish good Bohemian beer. Another advantage of "Krausening" is that the fermenting beer in the trade cask is less sensitive to severe cold and also suffers less from heat. This is important in shipments to long distances, and explains why it is customary in Bohemia to add a small amount of "Krausen" (one-half to one liter per hectoliter) even to lager beers which are intended for long distance shipments (export beers).
Beers that have been "krausened" can be sold younger than "Abzug" beers, and need not be quite clear when leaving the brewery, since they remain in storage at the public-house where they become clear, provided the beer was good to begin with, the "Krausen" is strong and the beer properly treated. This accounts for Bohemian breweries getting along with small storage capacity.
[edit] Bunging.
The bunging period differs widely for one type of beer. General rules cannot be given. In Munich the summer beers are commonly bunged for about two weeks, the younger and weaker winter beers six to eight days. Vienna "Abzug" beers are usually bunged one or two weeks, lager beers either not at all or not to exceed two weeks. Bohemian lager beers are generally bunged for a long time, viz., up to four weeks and over, particularly if the storage cellars are moderately cold and the beers old. The pale Bohemian beer which is generally more highly fermented requires and stands longer bunging. The practical brewer will readily see if a beer has been bunged enough by drawing a sample through the try-cock. When the beer is agitated in the sample glass, numerous tiny bubbles of carbonic acid gas should rise in it slowly. It is a bad sign if the carbonic acid liberated by the agitation escapes quickly.
In draught (Abzug) and lager beers that arc to be racked clear it is customary, in order to obtain the necessary life, to bung the casks tightly, thereby preventing the escape of carbonic acid gas and creating a pressure in the same.
The influence of temperature and bunging on the carbonic acid content of beer is shown by Langer and Schultze. The amount of carbonic acid in worts of 10 per cent B., in which 57 per cent of the extract was apparently fermented in the principal fermentation, was:
| Decrease of carbonic acid content per 1° C. | ||||
|---|---|---|---|---|
| At 0.4° C. | = | 0.332 per cent | = | 0.010 per cent |
| At 1.6° C. | = | 0.326 per cent | = | 0.010 per cent |
| At 2.8° C. | = | 0.311 per cent | = | 0.008 per cent |
| At 4.0° C. | = | 0.297 per cent | = | 0.012 per cent |
| At 4.7° C. | = | 0.297 per cent | = | 0.017 per cent |
| Average | = | 0.012 per cent |
It may be said that within the range of temperature from 0° to 5° C., the carbonic acid content of a Vienna "Abzug" beer, with equal pressure, rises or falls by about 0.01 per cent, according as its temperature rises or falls by 1° C.
The carbonic acid content of this Vienna "Abzug" beer when bunged for five and four days, respectively, showed an average increase for three tests of 0.046 per cent, i. e.. 100 g. beer after bunging contains 0.046 g. carbonic acid more than before bunging, or 100 c.c. of beer by bunging takes up an additional 23.8 c.c. of carbonic acid. For 36 hectoliters of beer this amounts to nearly 9 hectoliters of carbonic acid gas more absorbed by bunging.
To increase the carbonic acid content of beer 0.01 per cent, an average excess of pressure of 31.3 mm. mercury column at 0° C. was required. When bunging was over, the tension within the cask averaged no more than 0.19 atmospheres.
The largest amount of carbonic acid that could be forced into this "Abzug" beer by the lowest cooling and moderate bunging at the same time was 0.390 per cent. The beer was excellent.
With 0.320 per cent of carbonic acid the "Abzug" beer of a brewery in Vienna was only medium good as to life and prickliness, but if the carbonic acid content fell below 0.320 per cent, the consumers began to complain.
[edit] Special German beers.
Besides the recognized types, like the Bohemian, Vienna and Bavarian beers, of each of which there are brewed two varieties, the Schenk or Winter Beer and the Lager or Summer Beer (see above), there are beers brewed for special purposes of each type like Bohemian Export, Vienna Export or Bavarian Export, or beers brewed for special occasions like Bock.
Export and Bock differ from the Schenk and lager in that they are brewed stronger and contain more alcohol. Thus the percentage of alcohol and extract found, as the result of the analyses of a large number of beers, was on the average:
| Alcohol. | Extract. | |
|---|---|---|
| Schenk or Winter Beer | 3.36 | 5.34 |
| Lager or Summer Beer | 3.93 | 5.79 |
| Export Beer | 4.40 | 6.38 |
| Bock, Doppelt or Marzen | 4.69 | 7.21 |
Beers are brewed in certain localities which have achieved a reputation far beyond the confines of their homes and which have certain peculiarities that distinguish them from the ordinary type.
Such are:
Kulmbacher.—A very dark beer with the Bavarian characteristics especially accentuated, brewed along the lines of a Bavarian lager, from a very strong, original Balling of wort of about 18 to 19 per cent.
For Braunschweiger Mumme, Broyhan, Weissbeer, Adam beer and other special German beers, see "German Top-Fermentation Beers."
