Stock Photo - Brewer Ann-Marie Ahrens pours hops into a mash tun at the Stoertebeker Brewery in Stralsund, Germany, 19 April 2016. The traditional Hanseatic brewery has been brewing beer since 1827. The Stoertebeker Brewery in Stralsund was able to increase its beer production in 2015. Compared to the previous year, beer sales grew from 123,000 to 140,000 hectoliters at the brewery. The beer purity law - the 'Reinheitsgebot' - was enacted by William IV, Duke of Bavaria on 23 April 1516. The law is considered the world's oldest food law, and mandates that only water, hops, and malt can be in the beer. Since people in the Hanseatic city have always been fond of drinking beer, the number of breweries in 15th century Stralsund was 216. Photo: STEFAN SAUER/ZB | usage worldwide. - Stralsund/Germany