Wheat beer production
When describing wheat beer production one distinguishes between various
stages of the process: mashing, lautering, boiling, cooling, fermentation
and storage. Mashing begins with the crushing of the malt in a grain mill.
After immediately adding heated water a so-called mash is produced in the
mash tun. The selection of water temperature in itself is of importance to
the subsequent quality of the beer because it activates the enzymes
present in the malt which then act on its components. An important
objective in doing so is to break down the existing starches into low
molecular weight, fermentable sugars. This break down occurs in part
mechanically through digestion and in part enzymatically. To this end a
mash extract is withdrawn from the mash which is then slowly brought to
the boil. This splits open the starch kernels and when the two partial
mashes are subsequently recombined, the enzymes of the unboiled mash are
able to act more rigorously on the released starch. This process can be
repeated several times depending on the characteristics of the malt or the
desired beer quality. Once starch breakdown is complete, the actual
mashing process is finished. Sugar is added to the mash and it is then
pumped to the so-called lautering tun.
Lautering
Lautering, or clarification as it is also called, takes place in the
so-called lautering tun. This is where, at 76 degrees, the solid
components of the mash (spent grains) settle onto the screen at the bottom
of the tun. These solid components form a natural
filter bed through which the fluid above, the first wort, is run off.
After the first wort has been withdrawn, heated water is poured over the
spent grain layer three times to fully remove all sugar (sparging). The
fluid as a whole that has run off is called the wort and is transferred to
the wort pan for further processing.
Boiling
The purpose of the boiling process in the wort pan is on the one hand to
boil down the wort to the desired extract (original wort), and on the
other hand to achieve a certain level of aromatization through the
addition of hops. The addition of hops also serves to precipitate out
undesired protein material which is then removed in the whirlpool, to
stabilize the head in the finished beer and to improve the shelf life of
the product. After a period of boiling of about one hour, the original
extract value is calculated - this is the ratio of dry material to liquid
- and the hot wort (cast-out wort) is cast out via the whirlpool. Protein
components that have precipitated out within the wort pan settle out in
the whirlpool in the form of a hot trub cone.
Cooling
Cooling of the wort by means of a heat exchanger is necessary because the
wort in the whirlpool is still almost at the temperature at which boiling
is performed. The heat exchanger is designed in such a way that the
recovered heat is returned to the energy cycle. During cooling of the wort,
the so-called cold trub precipitates out which consists mainly of
undesirable hops bittering compounds and low molecular weight proteins
which have combined with tannins from the raw materials.
*****
Wheat beer production
Bottle fermentation
When it is bottled, the young wheat beer contains only very little
carbon dioxide. Once the bottle is sealed, the pressure in the bottle
rises as a result of bottle fermentation and the carbon dioxide thus
produced dissolves in the beer and is only released once the bottle is
opened and the beer is poured out. This produces the head and the typical
sparkling and effervescence in the glass. Flavor maturation, which is
absolutely essential, also takes place during bottle fermentation. The
yeast settles at the bottom of the bottle, the wheat beer becomes clear.
The beer is bottle fermented at a temperature of 20°C for 7 days in a
so-called warm store, it then ripens for 3 weeks at 10° C in a cold store.
This bottle fermentation in the maturation chambers takes a total of 4
weeks. Draught beer is also treated in the same manner. Our wheat beers
are neither pasteurized nor heat-treated. Before our wheat beer leaves the
brewery, every batch is inspected and tasted by me personally. Only after
a series of quality tests do I release the wheat beer for sale through my
signature. I regard this final inspection as one of my most important
tasks. This guarantees that every bottle and every keg of Schneider Weisse
tastes good and satisfies our quality requirements. All brewing stages
from raw material purchasing to bottle fermentation are strictly
controlled. Our brewery has been certified in accordance with DIN ISO 9001
since 1996. We also passed an ecological audit in 1996. Numerous awards
and gold medallions attest to the quality of our products.
Fermentation
The fermentation of our prospective wheat beer is carried out in open
fermenting vats. The cooled wort (pitching wort) is placed into individual
fermenting vats where it is pitched with top-fermented yeast cultivated in
our in-house yeast cultivator. This guarantees consistent quality.
Maintaining the health of the yeast is a prime necessity for the master
brewer. That's why he takes such care to maintain ideal
conditions in the fermenting cellar. This is also where the so-called main
fermentation takes place. Precise temperature control is of the essence
here. Top-fermented beers are mostly kept at a warmer temperature than
bottom-fermented ones. This reduces the time required for main
fermentation accordingly. It is in the fermenting cellar that the malt
sugars obtained during wort production are fermented into alcohol and
carbon dioxide by the yeast. At the end of main fermentation the
top-fermented yeast rises to the top and is skimmed off. The ratio of
initial yeast to the yeast yield is about 1:4. The original pitching wort
has now become "young beer".
Storage
In many breweries, storage and/or secondary fermentation of the wheat
beer occurs in large stainless steel tanks. In contrast, secondary
fermentation and storage of Schneider Weisse occurs in the bottle or
directly in the keg. The finished wheat beer is ready for delivery after
about 4 weeks.
Bottling
The mixture of fermented young beer with yeast and "Speise"
(unfermented wort) is filled into bottles and kegs. We use only recyclable
bottles: the 0.5 l NRW bottle and the 0.33 l Vichy bottle. The bottles are
cleaned in a hot detergent solution and by means of a number of high
pressure jets. The final rinse is carried out with fresh drinking water,
this is followed by an electronic inspection for soiling, damage and the
correct bottle shape. The bottles are filled under counter pressure so
that no foam can form. The bottles are sealed and labeled. The label must
specify the type of beer, the production brewery, the list of ingredients,
the nominal fill quantity and the best before date (MHD). The bottles are
packed into crates and paletted. We also fill 20 l and 50 l standardized
kegs (KEG). A "KEG" is a upright cylindrical keg with a plastic
casing and built-in valve. The kegs are automatically cleaned with hot
detergent solution, filled, labeled and paletted.
|
