Acidulated Grain

So I have been having problems with hitting my OG. After posting my issues here, as well as talking with some employees of NB, I have started to move towards adjusting mash PH. I have ruled out the crush, my instruments, etc.. so the next thing to try varying is mash PH because I think my PH's have been high. The only batch I nailed my OG on was a stout- Higher roasted malts, higher acidity- possibly brought my PH into the correct range. I just bought a PH meter and some acidulated grain. I have a concern that my PH may be too high for even this to work, but I'm not sure. From what I've read, the rule of thumb is 1% of grain bill = .1 PH and that to avoid a sour flavor from the acidulated malt to stay under 10% of my total grain bill. What if I need to adjust for more than 1.0 PH? What other approaches can I take? Also, my plan was to dough in, stir like crazy and check the PH at room temp. ASAP so as to add the acidulated malt before too much conversion happens. I'm looking for suggestions regarding this process as I have never done it before... brewing tomorrow morning so any info would help!

Sorry for the epically long post. Thanks in advance!

 

I've read that up to 3% acidulated malt is acceptable with 2% recommended as a starting point. You could try the 88% acid solution to avoid the sour malt flavor and also get a faster change in mash PH if that's a concern of yours. That being said I'm just regurgitating what I've read recently so this advice is worth what you paid for it. I'll actually be doing my first brew with water additions hopefully tomorrow. Hopefully some others will chime in with more advice. Also you may want to post this over in the Brew Science section where the experts hang out.

 

Tell us more about your process. What are you using for your mash tun? What is your sparge method? What is your current efficiency?

What is the makeup of the water you're using? Have you tried brewing with RO or spring water?

When brewing all-grain, it's always a good idea to get a handle on your pH, but are you sure it's an issue? In my experience, high pH will not cause efficiency issues, but it will extract tannins from the grain, and that's definitely no good. Low pH will decrease efficiency.

 

10 Gallon round igloo cooler MLT- 5 gallon batches- Fly sparge with SS false bottom (which I know I have been running a bit too fast, so I will try and correct this tomorrow). Extraction eff. last brew was 67%- My volume ended .5 gallon high by accident making my brewhouse eff. 57%.

I don't have a full make up of my water- It's really hard 15 grains per gallon- PH 7.75. I tried getting a report from the city, but they weren't helpful. I haven't sent anything to Ward labs yet (trying to save $40). I have used distilled water for 1 of my batches- it didn't seem to help much.

According to Braukaiser, high PH also drastically affect efficency...

http://www.braukaiser.com/wiki/inde...ity_and_efficiency_in_single_infusion_mashing

Check out the Ph section...

 

This is subjective of course... I adjust mash PH with acidulated malt using a spread sheet for a ball park estimate based in my local water. I've come to the conclusion over the last 10 brews or so that I prefer a PH of 5.5 - 5.6. Lower requires more acidulated malt and either the lower PH or the malt itself compromises the beer. For me 2 oz in a 6 gallon batch is perfect, 4 too much and none too little. Note I also add gypsum generally to the mash and this is for pale hop forward beers, though these days I use 2 oz for my stouts also.

I suggest you experiment, take a PH reading and decide based in your taste.

Steve da sleeve

 

Interesting. I didn't realize that a high pH would impact efficiency, however, once you start to get into the 6.0 area and beyond, I would think that low efficiency would be the least of your worries. Of course, I'm no water chem expert, so it's no surprise that I could be full of it with regard to this topic.

How sure are you of the accuracy of your volumes both in the kettle and the fermentor?

When you used distilled water did you add any minerals back in?

Until you know the chemistry of your brewing water, it's going to be pretty difficult to modify it appropriately. You'd be better off using distilled or RO and then using the Bru 'n Water or EZ Water calculators to build up a profile for each recipe. Now that you have a pH meter, at least you can test the mash pH.

Hopefully, one or two of the resident water chemistry gurus will chime in before too long and offer their $0.02.

 

Yeah, I'm no expert either, hence all of the questions. I'm trying to read up as fast as I can, but there is a ton to know when troubleshooting efficiency. My volumes are close, not 100% exact, I have a scale that I marked out on my brewing spoon. When I used distilled, I didn't add anything back in. Unfortunately, I think I may have to go down the rabbit hole of brewing chem farther than I initially planned....

 

You can use lactic acid or phosphoric acid to reduce the pH in lieu of acidualted malt

You really need a water report though and a good spread sheet like Bru'n water

You could also use R/O water and build up that or dilute your tap water with r/o as well.

Ward labs is kit 5 or 5a I thnk and its like $27 IIRC

Sent from my SM-T310 using Home Brew mobile app

 

Out of curiosity, why has the crush been ruled out? Mash pH and mash thickness (among other factors) will affect mash efficiency, but not anywhere near as much as the quality and size of the crush.

 

I go to nb and I had them check the mills when I was there.


Sent from my iPhone using Home Brew

 

What did they check the mill for? Did they just check to see if the gap is where it normally is?

Also, are you getting inconsistent OG's (assuming consistent volumes), or you're just consistently below your target gravity?

 

The pH of your mash will certainly affect the efficiency of the amylase enzyme, which prefers pH 4.6-5.2. But as it has been mentioned, you must know your water chemistry and grain bill before you can take accurate pH measurements and make changes.

I tend to use 88% lactic acid to acidify my process in lieu of acidulated malt. Also, adjusting your pH only works if you don't have a pH meter, if you do, it never works. You probably only have a +/-0.2 pH accuracy anyway, worse with strips.

 

"The pH of your mash will certainly affect the efficiency of the amylase enzyme, which prefers pH 4.6-5.2."


Beta Amylase, 130 - 150°F, 5.0 - 5.6 pH. Produces small, highly fermentable sugars.

Alpha Amylase, 155 - 167°F, 5.3 - 5.8 pH. Produces larger, less fermentable sugars.

For that reason, in a properly executed decoction mash, the 1st decoction is converted at alpha temps when mash pH is higher. The 2nd decoction is rested at beta temps, due to the reduction of pH during the acid rest.

Enzymes that work at lower pH are outside the temp range of single infusion mashing and are denatured at conversion temps.

 

I didn't have time to run off enough RO water last time I brewed so I used 6% acid malt for a pale ale recipe. I have pretty hard water. This is the most acid malt I've ever used. I hit a mash pH of 5.6. But that's with my water profile. It didn't affect the flavor much that I can tell, but I did get a slight tartness in the finish when you take a sip. I actually like the tartness, it adds to this beer I think. But, that's probably the upper limit of how much I would want to use. If I needed to lower the pH some more, I would either use RO water or some phosphoric acid or something.