April 23^rd marks the 500^th anniversary of the Reinheitsgebot. Better known as the ‘German Purity Law’, the Reinheitsgebot is a medieval bit of legislation that stated only water, hops and barley could be used in brewing. Since then the rules have been bent and reshaped a little, but in Germany an ingredient-related beer law remains to this day. Brewers elsewhere – including southern Africa – also abide by the purity law for quality, heritage and if you’re a bit of a pessimist, marketing reasons. Rather than ramble on about what the law is or what I think of it (I reckon it’s great for those who want to follow it and not for those who don’t, if you’re interested), here are ten fascinating (well OK then, mildly interesting) facts about what is often erroneously referred to as the world’s oldest piece of food safety legislation (well, it was partly to stop brewers chucking toxic plants into their brews I guess, but more about fixing the price of beer and reserving the wheat and rye crops for bakers).

1. Yeast was only added to the acceptable ingredients in 1906, some 50 years after Louis Pasteur worked out that this was what turned malt tea into delicious, euphoria-inducing beer (until then, people assumed brewers stirred their beer with a magic stick).

2. The original law wasn’t just about ingredients. In fact, it was principally about money (isn’t everything?). The law set a maximum price for beer depending on whether it was brewed in summer or winter.

3. In 1986 a German brewer, Helmut Keininger, was jailed for adulterating his beer with chemicals. Such was the shame of being outed as an impure brewer, he committed suicide in his cell.

4. On a more cheerful note, when you drink a RHGB beer, you know it isn’t a high-gravity brew. Brewing a higher alcohol beer then watering it down post-fermentation is strictly verboten.

5. The law has morphed over the years and now has sub-clauses that allow the use of sugar in top-fermenting beers – ales – (to enhance flavour or colour as opposed to alcohol levels) and hop extracts, if you’re so inclined.

6. Strict Reinheitsgebot brewers cannot force-carbonate their beers. They either have to carbonate naturally (like bottle conditioning) or use CO2 harvested during the brewing process to carbonate their brews.

A cold glass of Reinheitsgebot-compliant pilsner

7. They also can’t use finings such as isinglass or Irish moss to clear up their beers. Beers can be filtered (After all, that’s taking stuff out, not putting it in) or simply left to condition for longer to help them clear up.

8. During World War II, the founders of Namibia Breweries, Hermann Olthaver and Carl List, couldn’t get sufficient quantities of imported malt, so rather than substitute for maize or rice or sugar, they simply stopped brewing.

9. The Reinheitsgebot is often accused of stifling creativity, but there’s nothing stopping a RHGB brewer from producing a smoky porter or an imperial IPA – just look at Cape Brewing Company’s Cape of Good Hops.

10. Speaking of which, in southern Africa there are only a handful of breweries that staunchly stick to the Reinheitsgebot – so this weekend, whether you’re a fan of the purity law or not, celebrate 500 years of beer tradition with a CBC, a Brauhaus am Damm, a Zebonkey or a Windhoek.

And for anyone who’s interested, here’s a translation of the original wording (thanks Wikipedia!)

We hereby proclaim and decree, by Authority of our Province, that henceforth in the Duchy of Bavaria, in the country as well as in the cities and marketplaces, the following rules apply to the sale of beer:

From Michaelmas to Georgi, the price for one Mass [Bavarian Liter 1,069] or one Kopf [bowl-shaped container for fluids, not quite one Mass], is not to exceed one Pfennig Munich value, and

From Georgi to Michaelmas, the Mass shall not be sold for more than two Pfennig of the same value, the Kopf not more than three Heller [Heller usually one-half Pfennig].

If this not be adhered to, the punishment stated below shall be administered.

Should any person brew, or otherwise have, other beer than March beer, it is not to be sold any higher than one Pfennig per Mass.

Furthermore, we wish to emphasize that in future in all cities, markets and in the country, the only ingredients used for the brewing of beer must be Barley, Hops and Water. Whosoever knowingly disregards or transgresses upon this ordinance, shall be punished by the Court authorities’ confiscating such barrels of beer, without fail.

Should, however, an innkeeper in the country, city or markets buy two or three pails of beer (containing 60 Mass) and sell it again to the common peasantry, he alone shall be permitted to charge one Heller more for the Mass of the Kopf, than mentioned above. Furthermore, should there arise a scarcity and subsequent price increase of the barley (also considering that the times of harvest differ, due to location), WE, the Bavarian Duchy, shall have the right to order curtailments for the good of all concerned.