Cluyn or ‘Groninger Haverbier’ is a medieval beer which was famous in the ancient city of Groningen, the Netherlands. This beer is brewed following a preserved recipe from 1476. With 40% oats, this beer is notable of its fine taste and soft mouthfeel. Delicately hopped with old type ‘Fuggle’. The only beer that used to be drunk warm.
In the fifteenth century, “Haverbier” or “Cluyn” was the answer of the Groninger Brewers to the German beers from Hamburg and Bremen that were taking over the market. These beers were brewed with hops and therefore more cost-efficient than the traditional “Gruit” beers of the Groninger brewers. The local brewers quickly adapted and started to brew with hops as well. They wrote down a standardized recipe that was used by most brewers in the city. This original recipe still remains at the Groninger City Archives. Our Cluyn 1476 is based on this ancient recipe.
The ratio is 40% Groninger oats and 60% barley malt, some of which is roasted. What is immediately noticeable with a beer that is brewed with so many oats is the gentle mouth feeling. This also makes the beer popular among those who are usually not real beer drinkers.
We brew this beer in two ways: with “ordinary” fermentation and with a multiple, mixed fermentation. With the latter method, freshly fermented beer will then get an additional fermentation of wild Brettanomyces yeast on oak barrels, which lasts about 6 months. This method brings us closer to the ancient medieval flavor since at the time all the beers with these wild yeast caused the fermentation in wood.
As a tip: sample these two beers with different fermentation methods next to each other, it will immediately be clear how much yeast affects the appearance of the flavors…