The history of beer dates back several millennia. Clay tablets found in Sumer, Mesopotamia, dating from 4,000 years B.C.E., mention a fermented drink called “sikaru”, which was made from barley, spelt, wheat and millet.
The Egyptians made a similar beverage, adding technical improvements to the process. The clarified form of the drink was given to the poor, while the more concentrated form, which was spiked with ginger and sweetened with honey, was reserved for the higher classes.
The Chinese had already developed an advanced process for making two kinds of beer – t’ien tsiou, a young "green" beer with low alcohol content, and tsiou, a stronger, finished beer. Later, rice-based beers won out over various grain-based versions, since brewers knew they could count on the high quality of the rice.
While the Greeks and Romans considered barley-based beverages fit only for barbarians (civilized people drank wine), the Gauls adopted beer as their national beverage in the fourth century B.C.E.
At a time when beer-making was mostly a family affair, monks in Germany, Austria, Belgium and France, began to develop the process for making beer.
In the tenth century, as people migrated to cities, brewing became a lucrative profession. Master brewers formed corporations to protect their profession and prevent the distribution of poor quality beer, which would harm their reputation.
In 1516, the Reinheitsgebot or Purity Law was enacted in Bavaria. This law applies even today and shows the ingredients (water, barley, hops) and production processes allowed.
In the mid-nineteenth century, beer making techniques underwent radical changes. Developments in the production of glass, filtration devices, pressure decanting, bottling and most important, refrigeration, made it possible to control temperatures throughout the crucial steps in the process. In the nineteenth century, when Louis Pasteur discovered the existence of micro-organisms, the process of alcohol fermentation was finally understood and further developed. Hygienic conditions at the breweries were improved around the same time, resulting in a healthier, clarified beverage.