Beer is the world’s oldest alcoholic beverage, possibly dating back to 9000 BC in ancient Egypt and Mesopotamia. From there is has been traced to the Greeks, then the Romans, then the British and Anglo-Saxons. The Irish and Germans spread brewing of beer through Europe as far back as 3000 BC. Any substance containing sugar or starch can undergo natural fermentation so it is likely beverages similar to beer were independently created by many civilizations.
Beer was thick in its earliest form, the result of crumbling baked bread into water to form a mash which was cooked into a drink. The process has become more sophisticated, sanitary, and standardized over the years and today consists of these steps.
1. MALTING
Barley cannot be used in its normal state because starch in its seed kernels is insoluble. In a process called malting, the grain is first soaked in a vat of hot water for about 40 hours. It is then spread out and kept moist for 3 to 5 days to allow it to grow tiny roots. The barley develops enzymes during this time to break down starch in the seeds into sugars. If left alone, the plant would use these sugars to grow leaves which, through photosynthesis, would allow the sun to take over the growing process once the sugars were gone.
Germination is stopped by drying the grain on racks in a kiln first at about 120°F, then at about 185°F. Drying at this temperature produces pale malt which can give the beer a pale golden color. Drying at a slightly higher temperature produces mild ale malt which can give the beer a deeper color. Drying at still higher temperatures produces darker malts which give the beer red, amber, and darker colors. This also gives the beer more substantial flavor.
2. MILLING
Malted grain is then ground in a roller mill. The object is to crack the kernels, leave husks relatively intact, and break the brittle starch inside them into particles that will dissolve in water.
3. MASHING
Milled grain is put in warm water in a large, insulated brewing vessel and gradually stirred and steam-heated to 113°F, then 144°F, then 164°F, resting for up to an hour at each point. This creates a sweet cereal mash as starch dissolves into the water and enzymes in the malt turn the starch into sugar. The sugar-rich water, a key part of the brewing process, is strained through the bottom of the vessel and is now referred to as wort (pronounced wert).
4. BREWING
Spent grains are filtered out and the wort is now boiled. It is during this stage that decisions are made regarding the flavor, aroma, and color of the beer. Different types of hops are added at different times during the boil as a preservative, to introduce bitterness to reduce the wort’s sweetness, and to give it aroma. The wort is boiled for one or two hours to sterilize and concentrate it and to extract desired essences from the hops.
5. COOLING
The wort is transferred quickly from the brew kettle into a heat exchanger to be cooled, filtering it in the process to remove spent hops. The heat exchanger circulates cold water through tubes to reduce the wort’s temperature. Yeast will not grow in high heat so cooling continues until a safe point is reached. The wort is also saturated with air to assist yeast growth.
6. FERMENTING
The cooled wort next goes into a fermentation tank where yeast is added. Yeast consumes the sugar and in turn creates alcohol and carbon dioxide. Every brewery has a selection of yeast strains, each of which can produce beer of a different character.
Lager yeast ferments at about 34°F. It works slowly, taking about 30 days, and sinks to the bottom of the tank when the sugar is largely consumed and fermentation is complete. It produces some aroma but allows the aroma of the hops to be prominent.
Ale yeast ferments at 60°-75°F and completes in 7-8 days. It rises to the top when fermentation is complete where it is skimmed off. Ale yeast produces more flowery aromas in addition to those produced by the hops.
Some Belgian beers achieve fermentation through spontaneous action of airborne yeasts natural to the region.
7. MATURING
The wort is now beer but is not yet complete. It is next moved to a cold-storage conditioning tank where it ages at between 28°F and 40°F for several weeks. The taste ripens and the liquid clarifies as yeast and other particles settle.
8. FINISHING
Matured beer is filtered one or more times to achieve sparkling clarity then is carbonated. It then goes to a holding tank where it stays until canned, bottled, or kegged. Filling techniques ensure that no air comes into contact with the beer or gets trapped in the container.
Exotic beer flavorings can be introduced along the way. Smoky flavors are added after malting. Fruit containing sugar is added before fermentation so it will be consumed by the yeast, but fruit flavorings are added afterward. Flavors such as coriander, ginger, or licorice can be added to the finished beer. Next time you enjoy a beer consider the care, effort, and science it took to produce.
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“Without question, the greatest invention in the history of mankind is beer. Oh, I grant you that the wheel was also a fine invention, but the wheel does not go nearly as well with pizza.” — Dave Barry
“A herd of buffalo can only move as fast as the slowest buffalo. And when the herd is hunted, it is the slowest and weakest ones at the back that are killed first. This natural selection is good for the herd as a whole, because the general speed and health of the whole group keeps improving by the regular killing of the weakest members. In much the same way, the human brain can only operate as fast as the slowest brain cells. Excessive intake of alcohol, as we know, kills brain cells. But naturally, it attacks the slowest and weakest brain cells first. In this way, regular consumption of beer eliminates the weaker brain cells, making the brain a faster and more efficient machine. That’s why you always feel smarter after a few beers.” — Cliff explaining the Buffalo Theory to Norm on Cheers.