So are there any down sides to always doing a protein rest? It seems to me that given the potential benefits in clarity, head retention and conversion, it might be a good thing to work into a standard brew- day protocol.
Not so much a down side to
doing the rest, there is a downside to resting
too long.
I generally perform the Fix 50/60/70 mash schedule, using infusions to raise the temperatures. Fix, Narziss
et al recommend keeping the 50C rest 15 minutes or less if highly-modified malts are used.
That's crucial, so I'll say it again: Fix, Narziss
et al recommend keeping the 50C rest 15 minutes or less if highly-modified malts are used.
Too long at this temperature permits too much of the foam (and haze) -enhancing proteins to be broken down. Yes your beer will be star-bright, but foam retention will be terrible.
I perform these rests for two reasons:
1. The 50C rest means I don't need to use 'foam-enhancing' specialty grains like wheat malt, flaked grains, or CaraPils. I can fine-tune foam formation and retention
and finished-beer clarity with one technique.
2. The 60 and 70C rests permit me to fine-tune my ferment. Here's Fix on the subject:
The ADF* is greatly influenced by the times spent at 60 and 70C. E.g., 15 mins. at 60 followed by 45 mins at 70 will typically drop the ADF into the low 70s**. The reverse will increase it into the mid 80s.
Note that the above is in reference to Fix's 'house' ale yeast. His experience told him how his yeast metabolized maltotriose, and those rests have a profound impact on the maltose/maltotriose ratio. I've found that my house ale yeast - Nottingham - is affected by those rests and rations as well.
This is important when formulating beers like IPA, where you want the beer to be dry, or Scottish Ales, where the result should be malty-sweet. Flip the 60/70 rest times for either result instead of adding specialty grains or sugars.
Plus it
really gives you something to crow about at the next homebrew club meeting. Even though it's not an advanced technique
at all, people are really impressed by step mashing. I mean, how hard is it to add boiling liquor to the mash? :? I've found that I get perfect results using my countertop tea boiler - it's got graduations on the side and can bring enough liquor to a boil in a very short period of time. (Of course, I do 2.5-3 gallon batches. You 10-gallon boys might need a different plan!)
Take up the gauntlet. Simplify your grists and step mash!
Regards,
Bob
* ADF = Apparent Degree of Fermentation
** in percentages