Its another one of Mike’s beers this week. We sample a re-brewed version of his brown ale and discuss a secret problem in his brewhouse.
I confess that I have had several beers over the last couple months that just refused to ferment out and attenuate as much as I would have liked. The primary issue I think can be tracked to some issues with my mashing setup.
My direct fired mash tun works great for the most part. It heats up strike water fast and I get great efficiency with my wort recirculation. The problem is holding a constant mash temp. Until recently, I didn’t have any insulation or a lid on the MT. I switched some things up bought some reflectix and made a nice jacket for the MT. I also carved out some pink foam core board for a lid. I had a definite difference in performance when I rebrewed my latest brown ale. I went from one beer with a 1.019 finish to a 1.010 finish on the second brew.
The primary difference was a closer attention to maintaining temps in the stainless steel MT. I think what was happening is that if the temp dropped too much I had to apply some heat. But the further away that temp was the more heat I had to use to catch back up. This I think lead to superheating of the wort at the base of the tun and denatured enzymes. Coupled to this issues was that I had been experimenting with No Sparge brewing. In no sparge, brewing all the water goes into the tun for the entire batch. Its pretty well known (although bot paid attention to by me I guess) that the thinner the mash gets, the more easily the enzymes are denatured either by pH woes or temperature increases.
All these things summed up to create wort that is likely to have had to high a dextrin content leading to poor fermentation performance. Other little factors also came into play; like discovering I had a 20F difference in two different thermometers once I was at mash temp! Goos thing I use calibratable dial thermometers and I can reset the temperature on them.
I still ned a couple batches for experimentation, but I hopefully have my problem fixed. No more no sparge brewing and use much gentler heat cycling for that MT mash temp. Sometimes I still think that there is the obvious well accepted brewing information; but there is still a ton of info on best practices that has yet to really be well based out and discussed. When you have your own equipment and process dialed in an working well things are great. But when you deviate a bit from the norm there aren’t many resources to help you out. You better be able to put your own brewer’s hat on and figure it out.