adding dark grains at vorlauf

[JerseyJoe]

Glad to have found this thread after listening to Gordon Strong on Brew Smith on this topic. He makes a lot of sense, I love to see some one think out of the box. Link to show below. It should que to 19:10 into the show when they are talking about stepping specialty grains vs mashing them.
http://www.youtube.com/watch?v=0w0BfUARazw&feature=player_embedded#t=1149s

 

[JustusLiebig]

So I assume the roasted malts will still have an affect on the pH. The grain will acidify the steeping water or the mash water if it is added at dough in or end of the mash during the vorlauf. Would we still adjust our brewing salts and water according to the spreadsheets, or is there a certain percentage of acidity or buffering that is gained or lost in the steeping process?
If it's added at the vorlauf, are we just assuming a half hour or so of sparging(diluting) isn't enough to extract tannins?
Is anyone adding brewing salts to their steeping water?

 

[rockfish42]

So I assume the roasted malts will still have an affect on the pH. The grain will acidify the steeping water or the mash water if it is added at dough in or end of the mash during the vorlauf. Would we still adjust our brewing salts and water according to the spreadsheets, or is there a certain percentage of acidity or buffering that is gained or lost in the steeping process?
If it's added at the vorlauf, are we just assuming a half hour or so of sparging(diluting) isn't enough to extract tannins?
Is anyone adding brewing salts to their steeping water?

Tannin extraction occurs at high pH not low pH, adding dark grains lowers the pH. Low pH is actually desirable after enzyme activity in the mash is over for a variety of reasons.

 

[ResumeMan]

And to be clear, the (non-flavor) reasons that you add the salts are for the enzymes to work at the correct pH as they convert the starch to sugar. So when you are adding the dark grains, you are indeed lowering the pH, but that doesn't matter any more for mash purposes since you're waiting till conversion is complete.

Therefore, proceed with your salt additions as though there were no dark grains at all (I suppose that adding the grains will lower the pH in the kettle relative to a recipe with no dark grains at all, but that isn't as important of a factor in the brewing process [I think it's not totally irrelevant but I can't recall the details.])

 

[befus]

I sort of tried the BIAB version today. I mashed only four ounces of chocolate and waited til the final two minutes when I stir constantly to add the 8oz. of black patent to a porter I brewed. I then put the bag in another vessel and 'dunked' it in about two gallons of 170 degree water and added to the boil. I'll see if I can taste a difference in a couple weeks.