Say the words ‘sour’, ‘wheat’ and ‘Belgium’, and everyone will think about lambic. In the last two hundred years, brewers located mostly in Brussels, or West of Brussels, in the Pajottenland, have created a wonderful type of beer, that is mostly drunk only after one year, that is often blended with even older batches, and that ages beautifully. It was brewed in the early 19th century with lots of raw wheat, till about 60%. Today lambic brewers use about 35% of wheat.
The popularity of lambic today makes us forget that there was also another Belgian tradition of brewing sour wheat beers. East of Brussels, in places as Leuven, Hoegaarden, Diest… there was a specific tradition of brewing beers with lots of raw wheat (till 50/60%). The main difference with lambic is that they were meant to be drunk young. They were light in alcohol, and like the farmhouse ales from Wallonia, meant to be refreshing. They contained a lactic sourness. Especially Hoegaarden was known for its sourness, which often became too strong after a few weeks. Like lambic it was drunk uncarbonated. It was often taken straight from the fermenter, sometimes after only one week. The last old skool Hoegaarden was brewed by Tomsin in 1957. The same goes for the traditional wheat beers in the other cities. In Leuven, the last Peeterman, a darker wheat beer, was brewed in 1974. In contrast to lambic, we can consider these types of lactic wheat beers as extinct in Belgium.
One reason is of course the gaining popularity of pilsner beer after the second world war; another reason seems to be the so-called ‘professionalization’ of the brewing industry, doing away with the artisanal brewtechniques, and installing new hygienical standards. Because of modern filtering techniques, brewing with lots of raw wheat became too difficult. However, more important are the microbial differences. The contemporary Belgian witbiers are clean beers, fermented with a selected Saccharomyces culture, and without bacteria producing lactic acid. The original beers were cooled using a (sometimes wooden) coolship, and inoculated with some yeast from earlier batches after cooling, resulting in a mixed fermentation. In Hoegaarden, some would not even add any yeast. These beers were hopped, but as in lambic, brewers did use old, low-alpha hops, and often only 1/2 or even 1/3 of the quantity used in lambic. Souring mostly did happen rather quickly because of the lactobacillus-bacteria from the brewery surroundings, and sometimes coming from unboiled wort-additions (in contrast to lambic, where pediococcus are the dominant bacteria).
As we are located East of Brussels, between the cities of Diest and Tienen, it goes without saying that we have some interest in revisiting this style of young, lactic wheat beer.
This week we did a first experiment brewing with a rather big amount of unmalted grains. It wasn't our intend to historically recreate a specific example of this beerstyle, but just to learn how to brew with a serious amount of unmalted grains, and to get the specific taste of raw grains.
The grist did consist of 34% pale barley malt and 66% unmalted grains (30% wheat, 30% spelt and 6% oats). Mashing was a little more complex than normally. The first mashtun contained 90% of the barley malt. The second mashtun contained all the unmalted grain, and 10% of the barley. This was boiled first, for gelatinization, then cooled with cold water, mashed at 65°, and then heated to 80°. We couldn't use this grainbed for filtering, so we did use the old method of a 'stuyckmand'. The liquid was run of by pushing a basket in the grainbed. With a pump it was transferred to the second mashtun, for filtering. After half an hour of filtering, the wort was pumped to two boiling kettles. The first was boiled for 90min with an addition of Hallertauhops (from the garden), most at the beginning, a little bit at the end. The second wort was boiled without hops, for a quick lacto-souring. After the boil, the gravity of the first wort was 1032; the second was at 1020. We did ferment the main wort with a wild starter culture (which provides plenty of spiciness, so no coriander needed); the other with our home sourdough-culture.
After 5 days, the second wort has already soured nicely, fermenting at about 28°c. In a few days, it will be added to the other fermenters. The taste now is very bread-forward. I can imagine that a wheat beer like this could have been quite nice on a warm summer day. Anyway it needs a lactic touch to be really refreshing.