BREWING
THE ACT AND ART OF BREWING
For all the research that has
been done on this topic, brewing remains more of an art than an
exact science. Contrary to the drinking person's worst fears, the
procedure of brewing has not changed since medieval times. The
basic recipe and method is straightforward: Barley is turned into
malt. The malt is "cooked" in hot water, hops are added
as an agent by flavouring and preservation; and yeast is
introduced to bring about fermentation.
SOME BASIC DEFINITIONS
Beer: A generic term, encompassing all
malt beverages.
Malt: Grain that has been rendered
soluble after soaking, during which partial germination occurs.
Brewing: A process by which malt is
clarified and boiled to convert the starches into ferntable
sugars.
Bottom-Fermentation: Dating back to the early 1400's,
bottom-fermentation is accomplished at lower temperatures, and
requires a primary and secondary fermentation, usually five to
six weeks long, is the aging or maturing period.
Top-Fermentation: Top-fermentation is most widely
associated with ale. While it also requires two stages, the
maturing process is much shorter and sometimes has sugar added to
stimulate the aging process. The cask is then sealed to allow
natural carbonation. Occasionally dry-hopping, the addition of
whole hops, is conducted to counteract the sweetness of sugar.
The result is a classic hop aroma of bitter English ale.
Pasteurisation: Draft beer is racked (put in
barrels or kegs) directly from the maturation vats. If it is
first microfiltered, centrifuged, or pasteurised, it is not draft
beer, at least by traditional definitions. Since beer in bottles
and cans will undoubtedly be stored longer (on store shelves, for
example) than draft beer, the shelf life must be extended. This
is accomplished by microfiltering, centrifuging, or
pasteurisation. All of these processes rob beer of some of its
flavour and, therefore, draft beer is almost always preferable.
In defence of non-draft beers, many wonderful imported and
regional beers would be unavailable were it not for bottling and
canning. So we must gladly suffer this technology so we may taste
many different and wonderfully unique brews.
Microfiltering is just what it sounds like; beer is passed through microporous filters which take out everything not nailed down, including a lot of the aroma, body, and even flavour. This gives beer a very clear look but at a very high price. Most American beers are this way because surveys indicate Americans don't want a beer which is not perfectly clear. Of course most Americans don't realise this also robs flavoring and character.
Centrifuging spins the beer at high speed to separate the unwanted particles.
Pasteurisation extends the shelf life of beer. It is for that reason most bottled beer is pasteurised. Unfortunately, this process also kills yeast which in a sense kills the beer itself, making it impossible for it to continue fermenting naturally.
There are two main types of pasteurisation; flash and tunnel pasteurisation. Both are not good for the flavour of the beer. Flash subjects the beer to 185 degrees for 20 to 30 seconds while tunnel heats the beer at 140 degrees for just under an hour. Flash pasteurisation is the preferable of the two and is the method used most often by American beer companies.
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