Hefeweizen pH and acid malt

EZ water predicts that it would take about 5% of the total grain weight of 2% acidulated malt to get the mash pH of a 50% wheat/50% pilsner Hefeweizen to a pH of about 5.4 at room temperature with distilled water. This includes CaCl2 to get about 50ppm calcium.

Does this much acidulated malt raise any red flags? I plan on measuring pH with a meter but am planning a starting point for this brew for a single infusion mash.

No, shouldn't take that much. Assuming a DI mash pH of 5.75 with no sauermalz 5% would be expected to give you 5.25 - lower than you want and enough to make the beer taste lactic tart (of course a bit of tartness is wanted in a weizen so might be an interesting beer).

I'd start by checking the pH of a small amount of the grist (w/o sauermalz) and then base the sauermalz addition on the rule of thumb: 0.1 pH per percent. You could add that to the test mash and check again that the pH is about right or you could just add it to the main mash on brew day. Last one I did (60% Weyerman's wheat; 40% Weyermann's Pils) I got 5.4 with 3% sauermalz using RO with a little calcium chloride added. I wouldn't use more than that.

I was using a pH of 6 for wheat in distilled water which lead me to too much acid for a predicted mash pH around 5.4 at room temperature. Using 5.75 for both the Weyermann pilsner & wheat lowers the acidulated malt to about 3% of the total grain weight.

I did 3 test mashes recently (100g total grain each) with identical water & salts, but varied the 2% Weyermann acidulated malt by 1% increments (of the total grain weight). One test mash and the 0.1 rule-of-thumb would have been fine to determine what to do with the actual mash. Graphing the mash pH vs % acidulated malt and linear regression resulted in a change of 0.08 pH per 1% of acidulated malt. What was more interesting was that the predicted mash pH's were consistently VERY close to the test mash pH's for a beer with a significant amount of roasted grain. The pH meter was a freshly calibrated Hanna pHep 5.

Related question to Hefeweizen brewing...

This might be the beer to try a decoction for the first time. What temperatures would be a recommended (protien rest, sacc) using Weyermann malts? I'd most likely skip the acid rest and mashout (batch sparge) unless told otherwise.

When do you measure mash pH in a decoction mash?

I dough in a 99°F for a ferulic acid rest, step to 122 for a protein rest, then raise to 127 and pull the first decoction. That goes to 160 F for 10 min or so and is then taken to the boil where it is held for about 20 min. Returning the first decoction should get the rest mash up to 147 °F. I hold there for 10 min or so and then pull the second decoction. It is also raised to 160 and held for 10 min before being brought to the boil and boiled for 10 min. Returning that to the main mash should raise it to 158 °F where I hold for 10 or so minutes more before taking it to 172 °F for mashout. I've been using this for so long that I don't really remember how I came up with it but I am almost certain that I got it straight out of Eric Warner's wheat beer monograph in the AHA series. If you use the Weihenstephan 68 strain (Wyeast 3068) and ferment it at about 62 °F this can be a really great beer.

I measure pH at dough in, at every temperature step, after the return of each decoction and in the fermenter.

Thanks for deviating from the original question. I reviewed your decoction schedule.

To get some of the melanoiden taste from a decoction mash, do you have any opinion on a single decoction for the first time?:

Mash in at 130F protien rest (20 min) @ 1.2 qt/lb.
Add boiling water added to get to 152F (recipe single infusion temp).
Pull a thin decoction for mashout, slowly heat to boiling and hold for 20 min.
Add decoction back to mash tun, drain, batch sparge with 170F water to preboil volume.

I do plan to use that yeast, pitch at 55F and ferment at 62F (30C rule).

130 seems high for protein rest. Will be doing a batch of hefe this weekend and have mapped out a decoction schedule pretty close the one previously posted. 122 for protein rest is one I have seen in a few different places now.

As I noted in #5 I think I got this from Warner and don't remember ever deviating from it. This is definitely a case of not fixing something that ain't broke. It makes really good beer. I suspect, but cannot verify, that the secret is in the 160 °F rests within the decoctions. This is letting alpha amylase go to work without denaturing the beta amylase most of which is back in the rest mash. With 2 decoctions of 40% each 64% of the malt would get the 160°F rest as opposed to 40% if you only do 1 decoction. I'm sure a single decoction would produce a fine beer but the double might produce one a little finer.

Does the decoction for the mashout have grain in it? I've seen people refer to a "thin" decoction for this, where a "thick" one seems to be described as the consistency of oatmeal...

In a triple decoction the purpose of the third is solely to denature the enzymes and so you want to make sure no starch is released. Hence, you make sure there is no starch to release and make this decoction liquid only. Note that not only is the liquid boiled denaturing any enzymes it contains but when returned it should bring the rest mash up to mashout temperature.

In this double decoction the second decoction, when returned, brings the temperature up to 158 - below mashout temperature. Therefore, you do not worry if a bit more starch is released. This second decoction is, while somewhat thinner than the first, still reasonably thick.

Then my plan in post #6 isn't much of a decoction because I'm just boiling wort to get from 152F to mashout. It is more concentrated wort at that point.

True but you should get some extra melanoidin formation.

I've reviewed AJ's decoction mash schedule and have decided to try this because a decoction has been something I've been wanting to try. Here's what I came up with for a plan based off Promash and information from Kai.

It's for a mash in a cooler with 1 infusion step and 3 decoctions.

My hefe brew was a mixed success - used two decoctions (one thick, one thin) rather than three but the pot I used for the decoction boils was a wee bit small - had to supplement with infusions of boiling water to attain correct temp. Next time!

Was a tad concerned when the wort had a grey hue to it - not the prettiest thing in the world. But it cleared up in the boil and a peek this morning showed me a pretty pale straw color. Whew!

ajdelange said:

No, shouldn't take that much. Assuming a DI mash pH of 5.75 with no sauermalz 5% would be expected to give you 5.25 - lower than you want and enough to make the beer taste lactic tart (of course a bit of tartness is wanted in a weizen so might be an interesting beer).

I'd start by checking the pH of a small amount of the grist (w/o sauermalz) and then base the sauermalz addition on the rule of thumb: 0.1 pH per percent. You could add that to the test mash and check again that the pH is about right or you could just add it to the main mash on brew day. Last one I did (60% Weyerman's wheat; 40% Weyermann's Pils) I got 5.4 with 3% sauermalz using RO with a little calcium chloride added. I wouldn't use more than that.

Click to expand...

I brewed my hefeweizen and the advice above was sound. The water was RO, verified to have very low TDS, only calcium chloride added to 48ppm Ca.

A test mash with the brewing water and grains (50% Weyermann pale wheat, 50% Weyermann pilsner), no acid malt resulted in pH 5.72. Adding 3% of the total grain weight acid malt reduced the pH of the test mash to 5.52. That information was used to boost the acid malt weighed for the actual mash to 3.3% of the total grain weight and the actual mash pH @ 15 min was 5.40.

Fresh pH calibration packets were used and the meter was calibrated immediately before each reading.