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Thursday, October 28, 2010

Brew 101



WHAT IS BEER?

Quite simply, beer is fermented, hop flavored, malt sugar tea. There are four basic building blocks needed to make beer: water, malted barley, and hops. Yeast, (often listed as a fourth ingredient, but not a part of the finished product) is used to ferment the hop flavored malt sugar tea into a effervescent liquid with an average of between three and seven percent ethyl alcohol by weight. (In some cases, such as a Barley Wine, the alcohol content can go to almost 11% by weight.) Both beer and ale are made from essentially the same four building blocks with the major variation being the type of yeast used to ferment the product.


The following is a brief description of the four important building blocks of beer.


1. Water:
Water comprises over 90% of beer. In the past, the mineral content of natural springs constituted a major flavor factor in the beers that were produced in a specific region. Examples of naturally occurring water supplies that have resulted in distinctive beer styles are found at: Burton-on-Trent in the United Kingdom, (Bass Ale) and Saint Arnold in Houston, TX.



2. Malted Barley:
Malt (from the Old English – mealt) is any cereal grain after germination and before fully sprouting. This is
 “malted” grain. To those involved in the brewing and production of fermented malt beverages, “malt” is the germinated, dried and perhaps slightly roasted grain of barley (Hordeum vulgare).




3. Yeast:

Yeast is the organism that metabolizes the sugar (maltose) in the wort into ethyl alcohol and carbon dioxide (CO2). The fermentation process is done in two steps. The "primary" fermentation converts most of the maltose to ethyl alcohol and CO2. The "secondary" fermentation finishes metabolizing the remaining sugar into the CO2 necessary to give the beer effervescence.



There are two kinds of yeast used in fermenting brew: Ale Yeast: (Saccharomyces Cerevisiae) aerobic yeast that needs contact with oxygen to ferment, so it forms a thick layer at the top of the wort. It also works best when the ambient temperature is between 60-65F. Its fermentation also produces Esters. These are flavors that give the impression of apples, pears and, sometimes plums.


Lager yeast: (Saccharomyces Carlsbergensis) An anaerobic yeast that ferments at the bottom of the wort and functions best at temperatures between 35-40F. It produces few esters and takes much longer than ale yeast to complete fermentation.
4. Hops:

Hops are the resinous flower that comes from the Hop vine, and they come in many different varieties. Different brewers use different varieties of hops depending on the flavors they desire. The brewers of Burton-on-Trent prefer the flavors of Kent hops for bittering their ales, while the brewers of Pilsen in the Czech Republic have the aromatic hops of Sazz to finish their lagers with. In the United States the brewers of the West Coast have long had a love affair with the Cascade hops of Oregon, while the brewers of the mega-brews have succeeded in blending hops until their flavors just nip at the senses. Each variety has a particular bitter flavor as well as aroma. These two characteristics are important to remember when tasting a beer.


This concert of the bitter flavor and floral aroma from the hops, when combined with the sweet and, sometimes astringent, flavors of the malts used in the beer are also influenced by the flavors created by the specific yeast used to ferment the beer.

Adjuncts:

Although malt and hops are the main contributors to the flavor of beer and ale, in some cases there are additional flavors. Depending on whether you are drinking a beer or ale you will also detect flavors that are created by the yeast during fermentation. The ale yeast creates esters that smell like apples, bananas, pears, and oranges.

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