If you love beer, then you've definitely heard about (and tasted) beers that claim to be made in compliance with Reinheitsgebot. Reinheitsgebot beers may even be your favorite of all the beers. Believe us, you wouldn't be alone.

But do you know what Reinheitsgebot means? Once again, you wouldn't be alone if you didn't. Most people, even the Germans who uphold it to be the best in the world, don't fully understand the history and implications of the term Reinheitsgebot.

Don't worry! We've put together the ultimate guide to Reinheitsgebot that will help you understand what you're drinking and impress your friends next time you're at the speakeasy.

What is the origin of Reinheitsgebot?

When the Reinheitsgebot or "purity order" was first adopted in 1516 in Bavaria, it was not what we know it as today. It was first and foremost a financial law in several parts. The first few parts created a pricing system for beer based on the seasons, and the last section declared what profits innkeepers could make from beer sales.

It was only toward the end of the law that the list of restricted ingredients makes an appearance—that beer could only contain water, barley, and hops. This section of the law has led many to herald it as one of the first consumer protection laws in Europe, but this aspect of the law was mainly crafted to have economic implications. It was meant to prevent beer makers from competing with bakers to buy wheat and rye, which kept bread prices from skyrocketing.

The law could also be seen as a protectionist measure to undermine the Northern Germany beer imports which used ingredients that Bavaria did not permit. If the products from North Germany contained ingredients other than those on the list, they could not be classified as beer in Bavaria.

Though not the main reason for the law, the law did end up protecting consumers from questionable additives like psychotropic mushrooms, marsh peat, and henbane (a poisonous plant from the nightshade family).

How did a Bavarian law become German law?

A fun fact about the "purity order" is that Bavaria forced Germany to accept this law several times as a condition of unification. When Bavaria reunited with Munich under Albrecht IV in 1506, both Bavaria and Munich had precedents in their own laws for Reinheitsgebot. Both had already restricted beer to water, barley, and hops, and Bavaria had gone one step further by adding pricing restrictions. The 1516 law was mostly a rewrite so there would be one unified law for the new unified Bavaria.

When Bavaria unified with Prussia in 1871, they insisted that the beer law come with them. Unlike Bavaria, Northern Germany had a tradition of using other ingredients to make sweet, spiced, and fruit beers, so northern beermakers objected to the law. Instead, the German Imperial Law developed in 1873 allowed barley substitutes to be used as well as other ingredients, but any ingredient not on the original list of three was taxed.

In 1906, a law was created with separate rules for ales and lagers (with the lager rules matching the 1615 law) and enacted nationally, but then World War I once again ruptured Germany's unification. When the states reunified under the Weimar Republic, Bavaria once again demanded that their beer law be a part of the deal. This time, it was declared a national law from the get-go and became known as Reinheitsgebot or the "purity order" that we now recognize.

Is Reinheitsgebot still law?

Technically, it's no longer the law of the land. After the final reunification of Germany when the Berlin Wall was knocked down, Reinheitsgebot was incorporated into the tax code but still acted as legal guidelines for the creation of beer. However, when Germany joined the European Union, their strict rules for beer were seen as protectionism.

In 1987, Reinheitsgebot was repealed by the European court of justice because it violated Germany's free trade obligations. Instead, any ingredient allowed in food was also allowed in beer. Germany, by this point, had internalized the Reinheitsgebot as an important German tradition that ensured that German beers remained pure and of the best quality, so in 1993, they created a new purity law.

The Vorläufiges Biergesetz or "Provisional German Beer Law" created more lenient guidelines for beer. Under Vorläufiges Biergesetz, any bottom-fermented beer has to be made with only water, malted barley, hops, and yeast. A wider variety of malt can be used for top-fermented beers as well as pure sucrose or beet sugars. There are other regulations, but in essence, Germany recreated Reinheitsgebot with a modern twist.

Any beer not made following the rules of Vorläufiges Biergesetz cannot be labeled beer in Germany.

What is a Reinheitsgebot beer?

Even though Reinheitsgebot is no longer law, most German breweries still follow the original prescribed ingredient list of water, barley, and hops—though their barley is malted as per the more modern laws. Their main reason for doing so? The customers.

The first several hundred years of Reinheitsgebot, the law was strictly enforced by the government. By the 20th century, the rules became a little more relaxed, and as other beers were imported and some even made in Germany, claiming to sell a Reinheitsgebot beer was a marketing ploy.

The law was no longer required to be followed, so those that did follow it made sure to market that they were the flagbearers for the German tradition. After all, regardless of the EU ruling, the only true beer by German standards was and is a Reinheitsgebot beer.

Between the call to tradition, the beer's unique German identity, and the fact that German beers were known worldwide as being of high quality, the Reinheitsgebot label took on a life of its own. Now customers were the ones demanding the German breweries only create beers in the Reinheitsgebot manner.

Just as the Reinheitsgebot disrupted Northern German beer traditions after unification, it has stymied current breweries from experimenting with new recipes. Even if a brewery comes out with a new recipe that follows Reinheitsgebot traditions, customers often treat the new brews with distrust because most customers don't know what Reinheitsgebot truly means. What they do know is which beers have been traditionally marketed as Reinheitsgebot and, in many people's minds, anything new is not a pure, German beer.

The truth is, even with the three original ingredients of water, barley, and hops, there is a lot of room for experimentation. For instance, using different hops and barley from different parts of the world can drastically change the taste of a beer but still remain within the parameters of Reinheitsgebot. Brewers can also barrel-age their beer, an old-fashioned method of bringing taste into a beer without violating the purity law.

Newer, smaller breweries can more easily get away with experimentation, and many have been doing so, creating Germany's own version of a craft beer that is still traditional. Older breweries in Germany often don't see the point in experimenting. They have built their reputation and customer base with a certain beer and now are more interested in uniformity, than creativity.

Why isn't yeast mentioned?

Yeast wasn't originally mentioned in the 1615 law. While many people interpret this to mean that they didn't know about yeast, there is another more likely explanation—the original list only includes those ingredients that remain a part of the final product. Yeast is used in the process of creating the beer, but it is not a part of the finished beer.

Contrary to popular belief, they did know about yeast in 1615. In Middle Age brewing, a hefener's job revolved around yeast. Hefeners would harvest yeast from one batch of beer and add the right amount to the next batch. Taking this historic fact into account, the understanding of the law inherently changes. It's not that you can't use non-list ingredients to make your beer, it's that only water, barley, and hops are allowed to remain in the final product.

Added to the minimal information on the allowed ingredients, this interpretation of the law makes crafting a modern Reinheitsgebot more complex. You can use hops, but what about dry hopping? What about using oxygen to accelerate the wort? Technically that should be allowed, but it's not a technology they would have had in 1615, so is it in the nature of the law? PVPP, which is often used for clarity, doesn't remain in the final solution, so by the rules of yeast, it should be compliant with Reinheitsgebot. Right?

Creating a pure Reinheitsgebot beer is fraught with tough decisions in modern-day breweries, but it also adds extra steps that other brewers don't have to perform. For instance, many brewers add carbonation before they package it. This would be against Reinheitsgebot as the carbonation remains in the final product, so brewers have to capture natural carbonation during the brewing process. They also have to perform more steps to maintain the correct acidification of beer without the external acids most brewers use.

These extra steps add complexity to the creation of German beer, and as a consequence, Reinheitsgebot brewers are rightfully proud of their products. Whether these methods should be mandated by law, however, is still up for discussion.

What is the future of German beer?

In 2005, a German brewery, Klosterbrauerei Neuzelle, added sugar syrup to its bottom-fermented beer in violation of Vorläufiges Biergesetz. The addition of the syrup was a German beer tradition that pre-dated the Reinheitsgebot law. However, under German beer laws, their final product was not allowed to be called a beer in Germany. They took the law to Germany's court and won the right to label their product as a beer.

The court determined that the "purity law" was not protecting the health of customers, only maintaining tradition. As such, the law overreached in banning all non-list ingredients and interfered with the brewery's freedom of occupation. This ruling opened the door for more creative interpretations of the law when flavoring beer.

As brewers seek to compete in the craft beer marketplace, and more breweries resurrect old beer traditions, Germany's beer offerings have begun to vary from the strict interpretation of the 1615 law—even in those beers that can still be labeled Reinheitsgebot.

However, traditional Reinheitsgebot lager beers have made such a name for themselves through their history, quality, and simplicity of ingredients that they will likely remain the main beer export of Germany for all eternity, even if the "purity law" is one day completely overturned.