BIAB - Mashout + Batch Sparge Question

[TheNoni]

I can't seem to find an answer to this anywhere so here goes:

If you want to batch sparge after your mash using the BIAB method, do you pull the bag out AFTER you have raised the original mash to 170 and let it sit for 10 minutes THEN pull the bag out and sparge it in another bag at 170 degrees?

So basically you do the original 170 degree mashout in your first kettle for 10 minutes before you lift the bag out and put it into a second kettle of 170 degree water, correct?

Thanks a lot guys.

 

[tre9er]

If you have another pot that can hold enough water and the bag, you can heat that to 170 (subtracting that volume from what you use for the mash) and dunk the grains in that separate pot. If not, just gradually raise the temp of the mash pot to 170 and then pull the bag and squeeze (this would be a full volume, single vessel BIAB so you need to have ample space in that single pot)

I'm assuming you understand loss due to absorption too, right?

 

[TheNoni]

Yes I do. I have a calculator I have used for my past 2 BIAB brews (this will be the thrid) that have been pretty accurate.

The past two beers I just did a single vessel, no sparge method because I could fit all the water and the grain bill inside my 10 gallon pot.

This third beer is a barleywine and has a pretty intense grain bill and I won't be able to fit all the necessary water into one pot. Also, I am worried about efficiency since the grain bill is so large, so even if I could do it in one pot I think I would want to do a seperate sparge.

So this would be my first sparge beer. And like I said above I was just unsure as to whether you raise the temp in your first kettle to 170 and sit for 10 minutes before you take the bag out and dump it into the second vessel at 170 degrees OR if after the mash (60 minutes in my case) you immediately pull the bag out and dunk in the second vessel, without doing the 170 degree 10 minute rest.