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Brewing

History

Early References to Beer

Historical documentation shows that around 5,000 years ago, ancient Chinese civilizations were brewing a beer-like substance known as “Kui”. In fact, a clay tablet found in what was ancient Mesopotamia, indicated that brewing was a fairly well respected occupation during the time, and that the majority of brewers were women.1

Early traces of beer and the brewing process have been found in ancient Babylonia as well. At the time, brewers were women as well, but also Priestesses. Some types of beers were used especially in religious ceremonies. In 2,100 BC, the Babylonian king Hammuabi included regulations governing tavern keepers in his law code for the kingdom.2

Beer drinking accessories, such as mugs, have also been found in Israel, and date back to nearly 2,000 BC. 3


Egyptian Brewing

Beer was part of the daily diet of Egyptian Pharaohs over 5,000 years ago. Then, it was made from baked barley bread, and was also used as a sacrament in religious practices.4

The role of beer in Egyptian society was far greater than just a drink. Often, beer was prescribed to treat various illnesses. Beer was considered to be the most proper gift to give to Egyptian Pharaohs, and it was also offered as a sacrifice to the gods.5


Greek and Roman era Brewing

Based on historical evidence, it appears that the Egyptians taught the Greeks the beer brewing process. The Greek writer Sophocles (450 BC) discussed the concept of moderation when it came to consuming beer in Greek culture, and believed that the best diet for Greeks consisted of bread, meats, various types of vegetables, and beer or zythos as they called it.6

The Greeks later taught the Roman civilization the process of brewing, who in turn later taught the early British/Anglo-Saxons tribes.7


Brewing in the Christian/Medieval Era

The process of brewing beer grew tremendously during the rise of Christianity. This was primarily because of the roles that monks had in the production of beer. Monasteries were some of the first organizations to brew beer as a trade. Monks built breweries as part of their efforts to provided food, shelter and drink to various travelers and pilgrims.8

A large amount of Christian saints have relationships to brewing. Saint Augustine of Hippo, Saint Like the Evangelist, and Saint Nicholas all are considered to be patrons of brewing.9

Emperor Charlemagne, the ruler of the Christian kingdom around 770 AD considered beer to be an important part of living, and is often thought to have trained Christian brewers himself.10

Like in ancient times, women were the primary brewers during the medieval times. Women took over brewing after the monasteries had really established the process.


Types of Beer

There are four main types or families of beer styles, which are determined by the type of yeast that is used in the brewing process.

Ale yeasts are yeasts that ferment at relatively warmer temperatures, usually between 60 and 75 degrees Fahrenheit. Ale yeasts form a layer of foam on the surface of the fermenting beer, which is why they are referred to as “top-fermenting” yeasts. Ales are technically ready to drink three weeks after the fermentation process begins, but they are often left to age for longer periods of time11

Lager yeasts are very similar to ale yeasts. However, one of the main differences is the ability of the lager yeast to process a chemical compound known as raffinose. This is complex sugar compound that is created in the fermentation process. Lager yeast, unlike ale yeast, collects at the bottom of fermenting beer, and is therefore referred to as bottom-fermenting yeast. Lager yeast is also fermented at considerably lower temperatures, around 50 degrees Fahrenheit. The majority of beers in production today can be considered lager beers.12

Two other types of beer styles include beer of spontaneous fermentation and beers of mixed origin. Beers of spontaneous fermentation are very hard to come by, and the majority are produced in Belgium using wild strains of yeast. These types of beers are often referred to as Lambic. Beers of mixed origin can also be beers of spontaneous fermentation, or ales and lagers that have also been fermented by wild strains of yeast.13


Major Ingredients in Brewing

The major ingredients in the brewing process are water, a starch source, yeast able to be fermented, and a flavoring source.

Water is the major component of beer. Since different brewing regions have different compositions of water, it plays a major role in the taste and formation of beer. For instance, hard water is preferential in producing a stout, while soft water if preferential in producing a pale lager.14

The starch source in beer is what provides the fermentable component of the beer, and it also plays a major role in determining the strength and flavor of the beer. Typically, malted grain is the predominant starch source used in brewing. Malted grain is formed when the grain is allowed to soak in water, where the process of germination begins.15

The major flavor component of beer is hops. The flower from the hop vine is used to flavor and preserved the majority of beers in production today. Hops have been used dating back to monastery production of beer. Before the use of hops, beers were flavored with herbs, berries, and other plant substances. Hops provided many important characteristics to beer, including bitterness, aroma, and flavor.16

The final ingredient in beer is the yeast. Yeast is a microorganism that promotes the fermentation of the beer. Yeast metabolizes and breaks down the sugars from the malted grains. The by-products produced are alcohol and carbon dioxide. Yeast also helps determine the flavor of the beer.17


The Brewing Process

There are nine major steps in the brewing process, which include malting, milling, mashing, brewing, cooling, fermentation, racking and finishing.

Malting is the process where the barley grain is made ready for brewing. Malting is broken down into three steps, which help to release the starches in the barley. First, during steeping, the grain is added to a vat with water and allowed to soak for approximately 40 hours. During germination, the grain is spread out on the floor of the germination room for around 5 days. The goal of germination is to allow the starches to in the barley grain to breakdown into shorter lengths. When this step is complete, the grain is referred to as green malt. The final part of malting is kilning. Here, the green malt goes through a very high temperature drying in a kiln. The temperature change is gradual so as not to disturb or damage the enzymes in the grain. When kilning is complete, there is a finished malt as a product.18

The next step in the brewing process is milling. This is when the grains that are going to be used in a batch of beer are cracked. Milling the grains makes it easier for them to absorb the water that they are mixed with and which extracts sugars from the malt.19 Milling can also influence the general characteristics of a beer.20

Mashing is the next step in the process. This process converts the starches released during the malting stage, into sugars that can be fermented. The milled grain is dropped into hot water in a large vessel known as a mash tun. In this vessel, the grain and water are mixed together to create a cereal mash. The leftover sugar rich water is then strained through the bottom of the mash, and is now referred to as wort.21

Brewing is the next step in the cycle. Here, the wort goes to the brew kettle or boiler, where it is brought to a boil. This stage is where many chemical and technical reactions take place, and were important decisions about the flavor, color, and aroma of the beer are made.22 Hops may be added throughout the boiling process for bitterness and/or aroma. At the conclusion of the boiling, the wort is often set into a whirlpool, where the more solid particles in the wort are separated out.23

After the whirlpool, the wort then begins the process of cooling. This is when the wort is transferred rapidly from the whirlpool or brew kettle to a heat exchanger to be cooled. The heat exchanger consists of tubing inside a tub of cold water. It is very important to quickly cool the wort to a level where yeast can be added safely.24 Yeast is unable to grow in high temperatures.25

After the wort goes through the heat exchanger, the cooled wort goes into a fermentation tank. A type of yeast is selected and also added to the fermentation tank.26 When the yeast is added to the wort, the process of the yeast fermenting the wort sugars into alcohol begins.27

The second to last stage in the brewing process is called racking. This is when the brewer racks the beer into a new tank, called a conditioning tank.28 Conditioning of the beer is the process in which the beer ages, the flavor becomes smoother, and flavors that are unwanted dissipate.29

Finally, the beer enters the finishing stage.30 Here, beers that require filtration are filtered, and given their natural polish and color. Filtration also helps to stabilize the flavor of the beer.31 After the beer is filtered, it undergoes carbonation, and is then moved to a holding tank until bottling.