Decoction return time

[nexy_sm]

Hi all guys,

I am trying to figure out how long should one spend on returning a decoction after boiling to the main mash. What was able to find about this topic are a few fragments from Noonan's book. There he says that the decoction should be returned in the coarse of a few minutes to the half an hour, depending on the goal fermentability of the final wort.
What I usually do are munich dunkels where I use decotion to step from 60 to 72 degrees, and in this case since I want this beer to be heavy, I dump almost complete decoction immediately.
What should be like normal time of doing this when brewing "normal" light lager, like Pilsner or so. Is something like 10-15 minutes ok?

Best and cheers

 

[ajdelange]

I hope 10 - 15 minutes is OK because that is how long it takes me to do it and I have been doing it that way for years. I just don't think I could do it much faster than that though i could, of course, do it more slowly.

I have seen over the years many mash programs advocating various rates of temperature rise whether the rise be from direct heat, infusion or decoction return. One degree per minute sticks in my mind as that is easy to remember. I do recall Noonan's remarks about different rates if the beer is to be fully lagered (or something like that) which confused me then and would still do so now. If you are in agreement with the arguments that say you should pass through the amylase activity range gradually then you would want to return the second decoction more slowly. If you aren't then just do it at 1°/min if or even faster if you can. The best thing to do, of course, would be to brew the beer more than once doing it faster on one and slower on the other (ceteris paribus) and determine which gives you the beer you like better.