BEER
History
Beer has been around a lot longer than people realize. Early in this century, a jug was excavated in Germany that contained beer made sometime in the Fourth Century. Pliny mentioned the ancient Egyptians used corn to make a beer-like beverage; the Egyptian Book of the Dead, written about 5,000 years ago, shows beer made of barley. In China, over 4,000 years ago, people were making a beer-like drink called ‘kiu’. It was made of barley, millet, wheat and spelt. And consider the Pilgrims, the effect beer had on them, and where they finally settled: intending to colonize the area of Virginia, they stopped at Plymouth Rock because, “We could not now take time for further search or considerations, our victuals being spent, especially our beer” (early journal entry). Yes, beer was more than a summer cooler or a way to get a buzz. It was food. Unpasteurized, unfiltered, unadulterated – those weren’t even concepts people knew of. Beer was a source of whole carbohydrates, a nourishing meal that could be afforded by even the poorest. It was also a primary source of hydration before modern sanitation practices were discovered. The best way to prevent cholera or dysentery on the Oregon Trail? Drink the beer!
Barley was traditionally the principal ingredient, along with the local water, and wild, indigenous yeast. The ‘bittering’ balancing agent was usually some type of tree bark. Hops, though in use for a couple millennia, have become popular in only the last few hundred years. No doubt, it was discovered that the dried flower of the hop plant lent not only the bite we now recognize in beer, but also extended the life of the beer. The iso alpha acids in the flower prevent the growth of many types of spoilage bacteria (hence the creation of the IPA on the very long shipping route from England, around the horn of Africa, and on to India).
Beer succeeded especially well in areas where the possibility of wine production was limited by weather or terrain, as in northern Europe. Further, the monks of Germany, Belgium et al propagated beer as a beverage of the masses – as opposed to that of the aristocracy, wine.
Until the nineteenth century, with few exceptions, beer was always ale. It was defined by the yeast strain Saccharomyces Cerevisiae, the same yeast that is used in making bread**. No surprise then that the local baker often also doubled as a town’s brewer. In the early part of the nineteenth century, Emil Hansen isolated that one ‘exception’ in the larger area of Bohemia, where the fermenting yeast regularly fell to the bottom of the barrels, as opposed to rising to the top as usual. This strain of yeast, Saccharoymces Carlsbergensis (named for the Danish town where it was developed) was soon made available for commercial use, but it was a couple decades before anyone did. In 1843, a brewery in Plzen, released the first lager, now known as Urquell. Since then, it has become the dominant style in the world of beer, though what we now think of as a ‘pilsner’ (from Plzen) is only one of many types within the larger classification of lager.
**The first private brewery in the U.S. was built by Hans Christian in 1612. The first public brewery was established in 1632 by the West India Co. on what is now Whitehall Street. Not only was Sam Adams a brewer – but so was George Washington. By the turn of this century, the U.S. was the brewing capital of the world, with almost 2000 breweries. That number has grown over the past decade to over 3500. **
Production
Just like the fermentation of wine, sugar is a necessary component for the fermentation of beer. Barley is the time honored grain of choice in beer production. It doesn’t come with its own sugar, but it does have starch aplenty. Thus the first step in beer production is therefore turning that starch into sugar.
The process begins with germination: barley is steeped in hot water for a couple days to soften it, and then transferred to large low-ceilinged rooms that are maintained at a warm temperature and high humidity. After usually three weeks, the barley will germinate, or grow a sprout of nearly an inch. During this process, the enzyme amylase will develop in the core of the grain. This enzyme converts the starch to sugar (maltose and dextrin). This ‘green malt’ is then kiln dried, causing the sprout to drop off. The length and temperature of kilning determines the color and amount of sugar available. The lightest toasting produces blond malt with the most available sugar but the least color. Longer kiln firings produce darker toastings (and therefore darker beers), but reduce the amount sugar available for eventual fermentation. Black malt imparts no sugar at all.
The next step in brewing is similar to using a percolator for brewing coffee. Like coffee beans, the grain is first milled to smaller pieces to release starches. After milling, it is put into a mash tun (basically a stainless steel tank with a slotted floor) where hot water is sprayed over it and drained. This process is repeated several times. The liquid that drains away is called “wort.” As the wort drains, it leeches the color and sugar from the malted grains, just like brewed coffee. When the wort has pulled enough sugar from the grains above to reach the sugar level appropriate for this brew (a decision made by the brewer), it is transferred to a brewing kettle where boiling commences.
At this stage, selected types and amounts of hops are introduced to the kettle. The wort is then boiled for a couple of hours to achieve the following:
1. Sterilization
2. Evaporation of excess water
3. Elimination of volatile materials from the hops & malts through evaporation
4. Caramelization: as boiling continues, the liquid darkens
The hops that are added at the beginning of the boil lend bitterness (flavor!) to the beer. The floral and fruit notes found in some beers come from hops added just before the end of the boil. That part of the hopping process that lends those qualities is volatile and delicate, however, and may be lost after only ten minutes of boiling.
When the boil is done, the wort is removed, quickly chilled, placed in fermentation vessels, and yeast is added (pitched). The type of yeast strain added determines whether the beer is a lager or an ale and dictates the final stages of the brewing process. Ale yeasts (Saccaromyces Cerevisiae) prefer to live and eat at temperatures between 65 and 75 degrees Fahrenheit, so all ales are held in that range. As the yeasts start converting sugar to alcohol, they float to the top of the brew, which is why brewers refer to them as “top-fermenting.” The bodies of the yeast produce a large, thick cap which protects the raw beer through this stage (this was particularly important historically, when beers were made in large, open-top vats; the yeast actually prevented foreign objects and bad bacteria from falling into and spoiling the beer). After a fermentation of five to eight days the beer is transferred to storage, where it may go through a secondary fermentation. Finally, the brewer will add carbonation, as well certain fining agents (if he so chooses) prior to bottling, kegging or direct dispensing.
Lager yeast (Saccharomyces Carlsbergensis) is all around more delicate than ale yeast. While ales can be brewed relatively hot and fast with the yeast still protecting the beer, such treatment will kill lager yeasts. They prefer to live and eat at lower temperatures (between 50 and 55 degrees Fahrenheit) and to work much more slowly: ales can be made in less than a week, but lagers take up to 3 weeks to ferment completely and attempts to accelerate the process will kill the yeast. Lager yeast also settles to the bottom of the tank—bottom fermenting—which leaves the raw beer quite vulnerable to open air. Lager, therefore, must be nearly hermetically sealed to prevent spoilage during the fermentation process. Once fermentation of a lager is complete, the brewer then adds carbonation, fines or filters as he sees fit, and finally bottles or kegs his product.
Stylistically, ales are more bitter and fruity. Lagers tend to be lighter, with more delicate aromatics. Please note that these are general guidelines that have many exceptions: there are plenty of heavy, bitter lagers and light, refreshing ales.
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