Target Mash pH if Adding Dark Grains at Vourlaf?

[micraftbeer]

I've recently started logging my Mash pH and trying to target/adjust based on BeerSmith 2 predicted mash pH. So checking my recipe last night and seeing it predicted 5.48 without any acid additions, I was happy. I'm sure it's mainly from the dark/roasted malts in my grain bill.

Then while mashing in this morning, I hit a dilemma. In reading one of Gordon Strong's recipe books, he recommends a technique of adding the roast malts at vourlaf, to take the edge of some of the bitterness you can get. I've tried this in the past with great success, and really like the smoother taste I get from the dark malts in this way. But if the dark malts were the source of my low predicted mash pH, by adding them at the end of my 60 minute rest, that would mean my mash was done at a presumably higher pH based on my 2-Row and Munich malts that will be soaking for an hour.

Does anyone that tracks/targets mash pH also do this process of adding roast malts at the end of the mash? I'm going to measure my mash pH at a couple points along the way. I'm curious if my mash pH starts off high (say 5.8) for the first 60 minutes, but then drops to 5.4 at the end of the mash, I presume all the advertised great effects of a target mash pH will not be achieved, right? And if I used acid to lower the mash pH of my 2-Row + Munich mash, would things go awry in the beer's final taste if the pH dropped again after adding my roast malts at the end of the 60 minute rest?

Recipe for Black Lager:
12 lbs 2-row
3 lbs Munich
0.75 lbs Carafa II
0.5 lbs Chocolate malt

Mashing 2-Row and Munich for 60 minutes at 152F, adding the Carafa and Chocolate, then raising temp to 168F for 10 minute mash out.

 

[micraftbeer]

Mash done. Here's my numbers:

• Start of 60 minute mash at 152F with 2-Row & Munich: ph=5.85
• 25 minutes into mash: pH=5.56
• 45 minutes into mash: pH=5.54
• 60 minutes into mash: pH=5.54
• Mashed in Carafa & Chocolate, raised temp to 168F
• At end of 10 minute rest: pH=5.46

 

[Silver_Is_Money]

What kind of 2-Row did you use?

 

[micraftbeer]

Just Brewers pale malt Briess.

 

[Silver_Is_Money]

It seems to me like BeerSmith did a very good job of forecasting your mash pH.

What sort of water did you use for the mash, and how many gallons of mash water did you have? Did you add any minerals?

 

[micraftbeer]

9 gallons of mash water. City water run through a 3 stage non-RO filter. Added salts to hit a "hop forward"profile that my taste buds like based on water test results of my water after filtering.

But my main question is about adding the roast malts at the end of the mash. I do this because I like the effect it has of softening the harsh flavor edges of the dark malts. But with this process, it either means my mash rest is at 5.6, dropping down to 5.5 at the very end when the roast malts go in, it I add about at the start of the mash to hit 5.5 for the hour long mash and drop down to 5.4 at the end.

Just looking for mash pH junkie's opinions on which would be the better way to go?

 

[Silver_Is_Money]

I'd say that for this sort of recipe you should continue what you are currently doing. I'd say that your chosen level of mineralization is counterbalancing the alkalinity of your city water just about perfectly.

Briess 2-Row mashes in DI water at pH 5.57, and their Bonlander Munich does the same at 5.50 pH. That you are mashing at 5.54 pH makes perfect sense. The small amounts of Carafa II and Chocolate both weigh in with DI pH's of about 4.7, so dropping to 5.46 after they are added seems about right also.

If you had attempted this recipe using a 2-Row Pilsner instead of Briess 2-Row Brewers your initial 5.54 mash pH (which is perfectly fine) would have leaped up to about 5.75 (which is generally considered too high) on first guess.

 

[btcost]

I personally like to keep the room temp mash pH a little lower.

5.4 being the high limit.

I wouldn’t worry about later mash pH readings. Just the initial one.

For a similar recipe with my water. I would most likely have a small acid addition with the brewing salts. Hitting a mash pH of around 5.4.

Then vorlauf with the dark grains with no further concern for the mash ph.

I do acid adjust the sparge water. Targeting 5.5