The
Reinheitsgebot, the famed
German beer purity law, was enacted in
Bavaria in
1516. Literally "
Purity law", it allowed only
water,
barley and
hops in the beer. When the role of
yeast in the
fermentation process was recognized, it was added to the list. This law is also notable for being the oldest
consumer protection regulation still enforced.
The Reinheitsgebot was enacted in 1516 by Duke Wilhelm IV of Bavaria, modeled after a civic regulation in Augsburg. It regulated both the ingredients and the prices of beer. In 1551, the law was amended to include yeast. As Bavaria became part of a united German state in the late 1800's, the brewing aspect of the Reinheitsgebot was adopted throughout Germany.
It should be noted that modern Germany produces beers with ingredients outside those specified by the original law, primarily wheat in Weizenbiers and sugar in top fermenting beers. Additionally, the European Union has forced Germany to allow the import of non-"pure" beers, although beers brewed in Germany are still regulated.