What would you say if I told you that there’s a little-known mash procedure, one you can try today, that will take up more of your time and produce cloudy wort that’s just teeming with unconverted starch? Why, in the name of all that is good, decent, and respectable, would you ever want to do this? Well, for one thing, you’ll be in the company of such renowned Belgian breweries as Cantillon and Boon.
Turbid mashing is an old Belgian mashing procedure that contradicts just about everything we think we know about mashing. While we usually try to fine-tune our process to create crystal clear wort, a turbid mash produces wort whose level of transparency is on par with a nice, silty stream. The turbid mash, which is traditionally used in the production of lambic, offers two main benefits for brewers of Belgian sours:
- Raw wheat. Lambic historically relies on a large fraction of raw (unmalted) wheat, which requires that the brewer take on some of the work that would normally be performed during malting, namely degradation of proteins.
- Food for the bugs. A turbid mash is so-named for the cloudy, almost milky, appearance of the wort it produces. This is actually a good thing for sour beers because the residual dextrins that Saccharomyces won’t touch are just the thing to nurture mixed cultures of Brettanomyces and souring bacteria.
Performing a Turbid Mash
Despite the turbid mash’s esotericism and reputation for complexity, it’s not really any harder than a decoction mash, and only one special piece of equipment is required: You’ll need to get your hands on a stuykmanden, which is the Flemish word for what essentially amounts to a large colander. So if you have a largish, fine-meshed colander or sieve, you’re all set.