For any given Ale excepting Belgians(145-148F), I usually mash around 152F with the logic, I’ll get a medium body out of the brew but, and yes, I have calibrated my Mash temp gauge. The problem I’ve been having is my beers have been coming out so dry. I guess I’m treating my yeast too well. I’m going to start making my mash rot ~ 154F to get a bit more body in the mouth feel. Well, that’s my rant for the day. Maybe this should be a sticky?(Brewing Rant for the day) We all have our gripes no matter how small. :-\
Lately, when shopping for mashing thermometers I discovered 152 is still considered “dry”. Usually 152 is my target because overly dextrinous beers are very unappealing to me. I may bump it up a degree or two as well.
I really wonder just how much difference a degree or 2 will make.
This is where I’d love to see an experiment in Zymurgy on mash temps and finished beer. Identical recipes mashed at different temps up to like 160, using the same yeast, and do some taste-panel analysis. Mash temp is only part of the equation in relation to the beer’s finishing gravity and mouthfeel - yeast is huge here, I think. With something like US-05, even a 5-degree difference in mash temp may not be noticeable in the end.
Maybe this has already been done in a past issue?
what yeast are you using?
1-2df would be hard to notice - probably needs to be 3 to really tell. an experiment in Zymurgy would be cool hint, hint
??? From listening to talks by Jamil Z. I get the impression that a 2F change in mash temp is significant.
rot = rule of thumb
And from my own experience, I think it’s very minor.
For those that batch sparge, I can almost guarantee that after a few minutes you have variations of 1-2 degrees (or more) in different parts of the tun. Even if you initially stir a lot, corners, top surfaces, etc. are going to cool more quickly. Does it really matter? Not in my opinion.
it doesn’t matter whether you fly or batch sparge - the tun is the same 
I don’t think the type of sparge you do matters…most people will still have the situation you describe.
Here’s the conversion chart from Palmer’s book. There’s a significant overlap between alpha and beta amylase. It appears to be between 146 and 156F.
Without constant stirring there is going to several degrees difference around the tun. Add that to ± tolerance with the thermometer then its going to very difficult to get everything with in a degree or two. Just relax.
Tubercle just mixes grain to the appropriate temp water, stir for initial uniformity, close the lid and let it do its thing. Never made a bad beer.
Think about it for a minute, what is the sprouting temperature for barley seeds? Do they ever see 130F and live? if they never do, then what is the genetic advantage to having an enzyme that is only active above that temperature?
In other words, the enzymes are active far below those ranges, otherwise they wouldn’t be present in the barley. They’ll work slower and that may not be useful for brewing on a reasonable schedule, but those hard cutoff lines are just not realistic. Think of them more as temperature ranges where that enzymatic activity is emphasized, not the only range where it will occur.
I used batch sparging as an example because it pretty much assumes that no supplemental heat is added to the tun. Fly sparging is likely the same way. I probably should have just specified mashing in a cooler.
It has been my experience that FG correlates only loosly with mouthfeel. There have been many highly attenuated beers with a full mouthfell and poorly attenuated ones with thin mouthfeel. I expect that yeast plays a big role as well. The residual sweetness also depends more on residual fermentable sugars than on the actual FG.
Kai
I agree and I think personal preference is a really big part of the equation. Some people can drink beer up to 1.020 and enjoy it. I recently tapped a barley wine that finished out at 1.014 and I think it’s too sweet. In fact, anything above this level seems sweet to me. In the case of my barley wine, I should have upped the hops, but that’s for another thread.
Most of my beer finishes in the 1.010 to 1.012 range, generally on the lower side, and I think it has good mouth feel when I compare it to similar commercial styles.
My BVIP recipe finishes at 1.026, but between the hopping level, the dark malts, and the bourbon it doesn’t come across as sweet.
Without ever trying it, I couldn’t say for sure, but my gut tells me that I would think it was cloyingly sweet.
Some general information on Mash temps. Attenuation is influenced by mash temps, and for different mash temps you can expect a different range. This chart is an interpretation of attenuations in an infusion mash in Noonan’s book. With a single infusion mash at 149F Noonan says an attenuation of 75-80% usually results. This highlights the fact that to maximize attenuation we want to mash at the low end of this curve.