BIAB, Protein rest with mod/unmod grain

[JeffStewart]

I've never done a protein rest before and I need some advice.
I'm doing a stout with:

50% Pilsner (Weyermann)
40% Wheat Malt, Dark (Weyermann)
8% Roasted Barley (Simpsons)
2% Chocolate Wheat Malt (Weyermann)

The dark wheat malt requires a protein rest, but I'm pretty sure the pilsner doesn't. My question is, even with the modified malt should I just raise the temp to 122F for 20 minutes and then sacch. rest @ 149 for 90min? I want the wheat malt to add the body, but don't won't to sacrifice losing the body from protein resting the pilsner. If that makes sense, like I've said, I've never done a protein rest before.

Thanks in advance.

 

[barleyhole]

I think the protein rest will help mainly with the yeast healthiness through the proteolytic processes, but should not affect the proteins in fully modified pilsner malt. Probably not necessary, but it won't hurt. I would say either way will do fine. However, if you want body I would suggest a higher mash temp for the sacch. rest, or start it at 149 for 30 min and then raise to 155-157. ..or just keep it at 154 the whole time. The wheat will add stability to the foam/head, but the higher sacch. rest will maintain more complex carbs that cannot be eaten by the yeasties and give your finished beer more body.

 

[JeffStewart]

Ok, thanks. So rest @ 122F for 20min sounds good? Also, if I mash @ 154F do I still need a 90min boil to reduce any DMS from the pilsner malt?

 

[barleyhole]

Yeah, 20 min for the protein rest...plus you'll get some more time heating it up for the sacch rest. Personally I think a 60 min. boil is fine. I've only ever done 60 minute boils with Pilsner malt and never had any DMS issues. Wonder if you'd be able to taste it through the roasty flavors anyway!

 

[JeffStewart]

Good point! By the way, one more question if you don't mind. Do I add the grains when I've reached 122F or just add grains then heat it up to 122F?
Thanks again for all the help.

 

[barleyhole]

I would try and add the grain with the water hotter than 122, so that once some heat is absorbed by the grain, the temp levels off at 122. It really depends on how much water and grain you are mashing with your BIAB method. Of course you can always add heat if you undershoot the temps.