Acidulated malt--how much?

I like the Baron's suggestion in another thread of using acidulated malt to lower the pH for brewing pilsners, siasons, tripels, etc, where the addition of mineral salts to lower pH might be less desirable.

Anyone know how much? Northern Brewer says to use it as 1 -10% of the grist, but no indication of how to quantify the pH effect.

I would probably need to lower my pH by about .5 in an all base-malt pale mash.

In a mash with a residual alkalinity of 0, 1 % of acid malt will lower the pH by about 0.1. This is according to Weyermann.

I'll have to check my notes, but I do remeber seeing a pH drop of about 0.2 for 3% acid malt.

Do you measure pH?

Kai

I think that it is tough to say. Depending on the brand, etc. there is a host of varialbes that could effect the ammount of lactic acid in the malt. I think that you would have to empricially test it. Start with 1% test pH, add a couple ounces test pH, etc. You might have to do this for each mash or you might find its pretty consistent. Who knows, let us know, that might be a nice thing to try instead of 5.2 for me! The other thing you have to consider is that this is going to be the same as lowering your pH with lactic acid. Probably not much flavor contribution, but is that the acid flavor profile you want? For a pilsner, etc. it would probably be historically accurate, but do YOU want that flavor? Just something to think about.

[edit] Kai beat me to the punch, and I guarantee he knows more than me about it, so listen to him

Hrmm, good question. I wonder what the standard (if any) that exists. I find it interesting because I make my own and have noticed with a fairly young batch (1 day vs. say a 4 day or something ...which I haven't done yet) added at about 10% of the grist is not really sufficient to produce anything other than "Hrmm something different and good about this beer but I can't quite place it" when you taste it. What I am getting at is, you'd have to taste the grain and gain the experience necessary. I would imagine from among the producers of such malt that there exists a spectrum of intensities in the acid. My latest creation, I used quite a large amount...sufficient enough that I think I brought my mash pH too low! . Conversion took forever and a day...literally and I know this was the reason. Not sure how I'll handle the recipe in the future though.

Kaiser said:

In a mash with a residual alkalinity of 0, 1 % of acid malt will lower the pH by about 0.1. This is according to Weyermann.

I'll have to check my notes, but I do remeber seeing a pH drop of about 0.2 for 3% acid malt.

Do you measure pH?

Click to expand...

I haven't yet--my calculated mash pH based on water chemistry for an all-base-malt mash is about 5.7something. My experience confirms this--I've had great luck with mashes with normal amounts of crystal malts (5-10% of grist) without altering pH. (That amount of crystal could be expected to lower the mash pH by about half a point, per Daniels.)

Are pH test papers even accurate enough this sort of situation? I don't really want to buy a pH meter--maybe I'll have to talk to some of my scientist friends about borrowing one.

cweston said:

Are pH test papers even accurate enough this sort of situation? I don't really want to buy a pH meter--maybe I'll have to talk to some of my scientist friends about borrowing one.

Click to expand...

I believe they are good enough since pH meters are expensive and need baby sitting. I did however experience a 0.3 pH unit systematic error with the lot of strips I have (https://www.homebrewtalk.com/wiki/index.php/ColorpHast_vs_pH_meter)

I'll have to check my notes and see how much acid malt I needed to add to my Pilsner. I do remember that I also had an RA of ~0 (which is about 5.7 base malt pH). I must have been around 3% acid malt.

I don't think that you can taste the acid malt until you go over 5%, at this point I would play with the water chemistry first (increase Ca and Mg in the brewing liquer) and use the adid malt to get the mash the rest of the way.

Weyermann might be the only acid malt available in the US. I'm not 100% positive about this though.

Kai

Kai, since my Ph came in on the high side with a very basic recipe, you think I should get in the habit of adding 2% - 3% acid malt to my recipes? I have some PH strips, although I've never used them (and I think they're the cheap kind).

Or, would I be better-off just sticking to the PH buffer (when I remember the damn stuff)?

I have toyed with the idea of getting some of these:

strips

What do you guys think?

Looks like the problem with those strips is that the color chart imcrements in .25 starting at 5.5

(the scale goes 5.0, 5.5, 5.75, 6.0, etc)

Since you'd be targetting about 5.2, that doesn't help much.

cweston said:

Looks like the problem with those strips is that the color chart imcrements in .25 starting at 5.5

(the scale goes 5.0, 5.5, 5.75, 6.0, etc)

Since you'd be targetting about 5.2, that doesn't help much.

Click to expand...

Yeah that was what I was worried about too ...but the half steps are still better than a lot of the stuff out there.

This all seems like a lot of fuss when the obvious easier solution is to just use a little 5.2 buffer. Since your water is so close, you could probably just add 1/2 Tbs to the mash and be done with it. It'll stick your pH exactly where it needs to be without having to calculate or worry about anything. They claim, and others have said, that there is no flavor contribution. If I had your water, that's what I'd do. Just my $0.02.

Lil' Sparky said:

This all seems like a lot of fuss when the obvious easier solution is to just use a little 5.2 buffer. Since your water is so close, you could probably just add 1/2 Tbs to the mash and be done with it. It'll stick your pH exactly where it needs to be without having to calculate or worry about anything. They claim, and others have said, that there is no flavor contribution. If I had your water, that's what I'd do. Just my $0.02.

Click to expand...

To be honest, that is probably what I will do (or else do it manually with a combination of gypsum, calcium chloride, and/or epsom salts).

But since Pilsen water is very, very low in all of those minerals (lower than my water even before adding any mineral slats), the acidulated malt would be an attractive solution for trying to capture that particular style.