Mash pH high when brewing Wheat beers?

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bundy

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Guys, I've been having problems with my hefe's always being low mash efficiency. 3 from 3 strike rate of about 6 or 7 gravity points low when measuring post mash and it's been driving me crazy.

All my malt based beers have been fine and there abouts just wheat beer efficiency is way down.

I've never looked at water chem before, but decided to look up my water analysis and plug it into EZ Water. To my surprise when using my regular APA or IPA grain bills pH calculates around 5.6 based on my water profile.

When I put in my hefe grain bill pH calculates around 6.1. Since found darker malts lower the mash pH which makes sense.

I am presuming this high pH issue is at least contributing to my poor mash efficiency, (if not the total cause) but wondering if anyone knows the correlation and how much a bad pH can contribute to this?

I have some lactic acid and salts on order to adjust and try this one more time but appreciate any thoughts on this and what others have experienced when brewing wheat beers. (Might be one for Les)

Cheers
 
Hi Bundy,

the pH will heavily affect the efficiency, especially when at that level 6.1. You can look to reduce that with some lactic or some salts using the EZ water system to know how much to add based on your starting ppm for each.

A website to read that done the science on pH is Braukaiser, its complex but worth a read to better your knowlegde of mash and the pH effects.

My water is already quite good for that style, I do though add some acidulated malt for the lower pH or do an acid rest phase to get natural acids within the malt to bring that down to target.

http://braukaiser.com/wiki/index.php?title=Starch_Conversion#pH_and_brewing_water
 
I'm brewing a Hefe this weekend. I did some reading and asked a few questions and what I've chosen to do is not add any salts at all, but will add 2.9% sour/acidulated malt to bring pH down to 5.6 (without that the pH was predicted as 5.87).
 
Could low efficiency on a wheat beer grist have more to do with wheat gumming up your mash process?
 
You must use a large amount of dark malt in your APA and IPA for there to be a 0.5 pH difference between those and a wheat grist. Seems a bit odd to me, but assuming it is true then I would tend to use some phosphoric acid rather than lactic because you will probably need to use a fair bit and don't want it to impact flavour. Another thing to look at is your crush; wheat does not have a husk and you may find that you need to have the mill set a bit tighter to crack it open.
 
Thanks gents for the quick replies.

I have to note these are all calculated pH levels from EzWater so not measured. I was as surprised as anyone at the variable caused by the grain bill was shown as what it was.

I BIAB so no issue with stuck mash. Last crush I ran the wheat through the mill 3 times to be sure it was all cracked, but in reality that wasn't needed and made no difference when compared to previous attempts.

EzWater tells me (other than the salts I need) I will need about 6ml of lactic acid to bring my mash ph into range at around 5.4.

That is based on 88% strong lactic. I do have phosphoric acid already (20l in fact) and had considered using that but did not know the rates to use as EzWater doesn't show Phos acid as an option?
I too have read too much lactic can affect taste so does anyone know if substituting lactic for phosphoric what adjustments to make to what EzWater tells mere amount to use?

Thanks again guys, all valuable advice.
 
Hmm. I guess you've tried longer mash durations, a raise to mash out & sparging the bag? I getter better efficiencies from my small-volume BIAB wheat and rye brews if I do this. I did a low-alcohol 100% rye saison last year that took an age to get through my normal process, even with the smaller than normal grain bill, but efficiency ended up OK.
 
bundy said:
Thanks gents for the quick replies.

I have to note these are all calculated pH levels from EzWater so not measured. I was as surprised as anyone at the variable caused by the grain bill was shown as what it was.

I BIAB so no issue with stuck mash. Last crush I ran the wheat through the mill 3 times to be sure it was all cracked, but in reality that wasn't needed and made no difference when compared to previous attempts.

EzWater tells me (other than the salts I need) I will need about 6ml of lactic acid to bring my mash ph into range at around 5.4.

That is based on 88% strong lactic. I do have phosphoric acid already (20l in fact) and had considered using that but did not know the rates to use as EzWater doesn't show Phos acid as an option?
I too have read too much lactic can affect taste so does anyone know if substituting lactic for phosphoric what adjustments to make to what EzWater tells mere amount to use?

Thanks again guys, all valuable advice.
You can use phospheric acid, but it drops calcium out of solution..... best to use lactic, it is the same as using acid malt essentially.
 
fraser_john said:
You can use phospheric acid, but it drops calcium out of solution..... best to use lactic, it is the same as using acid malt essentially.
Yes but to drop the pH from 6.1 to 5.4 means he will need to use the equivalent of 7% acidulated malt which you may well be able to taste.
 
Black n Tan said:
Yes but to drop the pH from 6.1 to 5.4 means he will need to use the equivalent of 7% acidulated malt which you may well be able to taste.
Hi, I don't intend to use Acidulated malt, Just 88% pure Lactic acid form G&G. From what I read acidulated malt is just malt treated with Lactic acid anyway, and being a Wheat I am just using 50-50 Pils / Wheat as my grain bill.
.
Based on my water profile EZ water Calc says I will need 6ml of 88% Lactic Acid to drop to about 5.55 ph which is within the 5.4 - 5.6 range so not too bad if I use 7ml I get to 5.48. I need 8ml to get to 5.4 which may be a bit high for lactic (6ml may be too high not sure)

I do read too much Lactic can impart unwanted flavours so if anyone knew how much Phosphoric I could use instead of lactic I may go that way and use a little of each.


Thanks
 
bundy said:
<snip>
acidulated malt is just malt treated with Lactic acid anyway, and being a Wheat I am just using 50-50 Pils / Wheat as my grain bill.
<snip>
No it is not treated with lactic acid, it goes through an acid rest before being malted, creating a natural lactic acid in the malt itself. It is German Purity Law safe malt.

If you don't want to use lactic acid in either 88% form or acidulated malt, then look at using water salts to lower you pH, CaCl and CaSO4 both lower pH.

I use lactic 11% and lactic 88% in sparge and mash respectively and 6ml is not noticeable.

Do you test the water before & after dough in? I adjust mine at 20c before dough in to be around 5.5 to 6, then test after dough in. It is normally then so close as not to worry any further.
 
bundy said:
Hi, I don't intend to use Acidulated malt, Just 88% pure Lactic acid form G&G. From what I read acidulated malt is just malt treated with Lactic acid anyway, and being a Wheat I am just using 50-50 Pils / Wheat as my grain bill.
.
Based on my water profile EZ water Calc says I will need 6ml of 88% Lactic Acid to drop to about 5.55 ph which is within the 5.4 - 5.6 range so not too bad if I use 7ml I get to 5.48. I need 8ml to get to 5.4 which may be a bit high for lactic (6ml may be too high not sure)

I do read too much Lactic can impart unwanted flavours so if anyone knew how much Phosphoric I could use instead of lactic I may go that way and use a little of each.


Thanks
I was suggesting you should use acidulated, just providing some context to how much lactic acid you would be adding. 6mL lactic which would be equivalent to 5% acidulated should be OK, but any more and you MAY taste it.
 
fraser_john said:
Do you test the water before & after dough in? I adjust mine at 20c before dough in to be around 5.5 to 6, then test after dough in. It is normally then so close as not to worry any further.
Thanks again guys, all good points.

As to above, to date I have never tested my water, so this is all a first for me. The only "figures" I have are based on EZ Water Calc and my water profile as provided by the Water corp.

I will be testing pH next brew once my test strips arrive. That will at least give me an indication of what is going on.

Cheers and fingers crossed
 
Just remember "pH strips typically used by homebrewers are reported to mis-report mash pH by about 0.2 to 0.3 units lower than actual. Homebrewers should use caution when using pH strips. Without another means of pH verification, Brewers are advised to accept a pH strip reading that is about 0.2 units above their targeted pH to avoid undershooting the mash pH. A pH strip reading of about 5.6 to 5.7 should indicate an appropriate room-temperature mash pH of around 5.3 to 5.5. pH measurement by a calibrated pH meter is preferred." (from Burn Water)
 
fraser_john said:
You can use phospheric acid, but it drops calcium out of solution..... best to use lactic, it is the same as using acid malt essentially.
Since calcium is not a requirement in brewing water, losing some calcium via a phosphoric acid addition is not a big deal. More importantly, to create that calcium precipitation, the calcium concentration has to be at a fairly high level. Under that condition, the loss of some calcium is even less significant. So don't sweat the loss of calcium when using phosphoric acid.

Lactic acid does have its place in brewing. Due to the requirements of the Reinheitsgebot, German beers always include a significant lactic acid content from either acid malt or saurgut usage. Lactic acid is probably one of those nuances of German beers that make those beers what they are.
 
bundy said:
Thanks gents for the quick replies.

I have to note these are all calculated pH levels from EzWater so not measured. I was as surprised as anyone at the variable caused by the grain bill was shown as what it was.

I BIAB so no issue with stuck mash. Last crush I ran the wheat through the mill 3 times to be sure it was all cracked, but in reality that wasn't needed and made no difference when compared to previous attempts.

EzWater tells me (other than the salts I need) I will need about 6ml of lactic acid to bring my mash ph into range at around 5.4.

That is based on 88% strong lactic. I do have phosphoric acid already (20l in fact) and had considered using that but did not know the rates to use as EzWater doesn't show Phos acid as an option?
I too have read too much lactic can affect taste so does anyone know if substituting lactic for phosphoric what adjustments to make to what EzWater tells mere amount to use?

Thanks again guys, all valuable advice.
I use 85% Phosphoric acid food grade and without any salt additions for 33 litres of rain or ro water you will need 8 mils of acid {phos} to get a predicted mash PH of 5.0 approx according to EZ water.
if you add 8 gramms of calcium chloride EZ water says you need 6 mils of Phos acid. for approx the same PH. This is for a grist of 5 kilos of wheat in my imaginary sample that I created to answer your query. In real life with a real grist these figures will vary slightly.


Bundy, you can change the percentage amount for acid in EZ water by clicking on the percentage field and typing in the new percentage the same in the type of acid field in the software.

i hope this helps
 
FYI acid malt can be made by "seeding" the malt with lacto then letting the bacteria grow/colonise, or by spraying with a solution of lactic acid. Very rarely these days is acid malt made through spontaneous growth of lacto.

Both methods are a-ok by the Rheinheitsgebot.
 
I'm guessing he's referring to a recent paper finding that calcium needs for brewing are far less than we think. I'm going on what I've heard as I haven't had a chance to track it down yet, so don't take this as a recommendation or something. Hopefully mabrungard will elaborate.
 
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