PH drops by around 1 after prime fermentation, is this normal?

[Miles_1111]

That last three batches ( 2 stouts and 1 pale ale) I brewed all showed 'hugh' PH drop after prime fermentation ( before bottling ):
1. Stout - PH before fermentation: 4.81 ----- PH after fermentation: 4.04 ----- drop by: 0.77
2. Stout - PH before fermentation: 4.92 ----- PH after fermentation: 3.94 ----- drop by: 0.98
3. Pale ale - PH before fermentation: 5.35----- PH after fermentation: 4.08 ----- drop by: 1.27

The average PH drop is around 1, however, according to John Palmer's How to brew 'the wort Ph drops by 0.5 PH during fermentation', the 'hugh' drop in my beers seemed too much? Especially for the first two stouts, they tasted a bit sour ( but acceptable ), I guess because 'dark beer styles seem to taste better with a higher PH, between 4.3 and 4.7', right? Is PH drop by 1 after prime fermentation normal? Thanks a lot.

 

[bracconiere]

i don't remember testing the wort right before fermentation. but my mash is 5.3 or so and, my finished beer is usually around 4.2? so normal?

 

[Qhrumphf]

The drop is yeast strain dependent, in addition to other factors. English and Belgian yeasts can produce pretty large and rapid pH drops, sometimes finishing in the very upper 3s. Lager yeasts typically don't drop as far or fast, and often only hit the mid 4s. Wine yeasts can produce pHs in "sour beer" range down into the mid 3s. pH alone won't tell you sourness (the measure for that is titratable acidity, which gives you a better idea of the actual amount of acid present, not needed for clean beers but more helpful for sours), and a beer finishing in the 4s or even very upper 3s shouldn't taste sour.

In an average snapshot scenario I'd expect a beer to start fermentation around pH 5-5.1, and finish 4.1-4.2. Above 4.5 you can run into stability problems.

I used to think Palmer knew what he was talking about. I don't think that any more. His stuff is usually ballpark correct-ish, but he gets a lot wrong. It's helpful for new brewers. But don't put too much stock in it. There are better sources.

 

[Miles_1111]

The drop is yeast strain dependent, in addition to other factors. English and Belgian yeasts can produce pretty large and rapid pH drops, sometimes finishing in the very upper 3s. Lager yeasts typically don't drop as far or fast, and often only hit the mid 4s. Wine yeasts can produce pHs in "sour beer" range down into the mid 3s. pH alone won't tell you sourness (the measure for that is titratable acidity, which gives you a better idea of the actual amount of acid present, not needed for clean beers but more helpful for sours), and a beer finishing in the 4s or even very upper 3s shouldn't taste sour.

In an average snapshot scenario I'd expect a beer to start fermentation around pH 5-5.1, and finish 4.1-4.2. Above 4.5 you can run into stability problems.

I used to think Palmer knew what he was talking about. I don't think that any more. His stuff is usually ballpark correct-ish, but he gets a lot wrong. It's helpful for new brewers. But don't put too much stock in it. There are better sources.

it seems the PH drop in my beers are more or less in the right range then. But for stouts, finish PH in the mid 4s (but no more han 4.5) will help the beer tastes better than finish at 4.1 or 4,2 PH, that is correct, right?

 

[Qhrumphf]

If you're in the 4.0-4.5 range, I wouldn't waste any time, any effort, or take any risks trying to change it.

 

[thehaze]

My bitter hasn't cleared more over the two weeks since I packaged it which is a bit annoying. I had been hoping it would drop bright, as I dislike any sort of haze in my bitters and don't use auxiliary finings . Flavour is very good though and the vanilla aroma is interesting.

I did use a new pump though, which might have affected clarity by breaking up break material too much.

Those of you who have made bitters, milds, pale milds etc how have you found clarity once you have packaged it and let it condition etc? Preferably if you don't use gelatin or isinglass etc

View attachment 706036

it seems the PH drop in my beers are more or less in the right range then. But for stouts, finish PH in the mid 4s (but no more han 4.5) will help the beer tastes better than finish at 4.1 or 4,2 PH, that is correct, right?

Simple answer is " No ". A lot of NEIPAs finish ( due to heavy dosage of dry hops ) finish at 4.5-4.6-4.7, and so on... A lot of English ales fiunish at 3.9-4.0-4.1 and they are fine. Dry stouts are incredibly acrid for my taste and the pH of such beer reflects and increased acidity, but that does not mean the beer is off. pH is not everything.

It's important to know the yeast used in each beer. I've experienced that some English strains ( dry Nottingham comes to mind ) do create a beer with a lower final pH.

But I will say that your post boil/pre-fermentation pH for the two stouts mentioned above is way, way too low. It looks like you simply just added the roasted malts and everything, without adjusting water, and hoped it didn't go too low. Because 4.8-4.9 is a pH you usually can get with low minerality water and adding 15-20% roasted malts with a pale malt base. For stouts, some say 5.5-5.6 in the mash. I've done a few tens of dark beers and if my mash pH was anywhere between 5.2 and 5.6, even for dark beers, the beer turned out just fine. So I've settled for 5.4 for any type of beer.

 

[Miles_1111]

Simple answer is " No ". A lot of NEIPAs finish ( due to heavy dosage of dry hops ) finish at 4.5-4.6-4.7, and so on... A lot of English ales fiunish at 3.9-4.0-4.1 and they are fine. Dry stouts are incredibly acrid for my taste and the pH of such beer reflects and increased acidity, but that does not mean the beer is off. pH is not everything.

It's important to know the yeast used in each beer. I've experienced that some English strains ( dry Nottingham comes to mind ) do create a beer with a lower final pH.

But I will say that your post boil/pre-fermentation pH for the two stouts mentioned above is way, way too low. It looks like you simply just added the roasted malts and everything, without adjusting water, and hoped it didn't go too low. Because 4.8-4.9 is a pH you usually can get with low minerality water and adding 15-20% roasted malts with a pale malt base. For stouts, some say 5.5-5.6 in the mash. I've done a few tens of dark beers and if my mash pH was anywhere between 5.2 and 5.6, even for dark beers, the beer turned out just fine. So I've settled for 5.4 for any type of beer.

Thanks. I noticed that the PH of my two stouts is quite low. I think it is because I used CaCO3 in water treatment and CaCO3 is hard to dissolve in the water, for I can remember clearly that I saw quite a few undissolved CaCO3 in the mash water when I added the malt. The undissolved CaCO3 did not do it work which is supposed to bring up the PH. I will choose other salt like Ca(OH) to replace CaCO3 next time.