In 1516, the Reinheitsgebot—commonly referred to as the “German Purity Law”—initially went into affect in Bavaria. Though earlier variations of the law were adopted almost half a century before its official enactment on April 23 that year, the law eventually would go into effect across all of Germany.

Among other reasons, the law was originally adopted to control the price of grain used in the brewing process and only allowed brewers to use three ingredients in their beer: water, hops, and barley. The law has since been adapted to modern regulations, but its impact on the history of brewing and beer styles is still renowned today.

In honor of the 500th anniversary of the Reinheitsgebot, the American Homebrewers Association is celebrating its impact by encouraging homebrewers worldwide to brew their choice of two recipes: a Northern German Altbier or a spiced beer.

The Summertime Ginger Ale homebrew recipe uses malt, hops, and water, but also tosses in honey, lactose, and ginger to really throw those Reinheitsgebot purists into a dizzy.