Dryhops and acidify casting wort

[aeviaanah]

We typically target kettle pH around 5.2. I heard some interesting ideas yesterday (Master Brewers Podcast Ep 217) regarding dryhops effect on finished beer pH. In the podcast, he mentions 1lb dryhops per bbl of wort could raise finished beer pH by .1. This is a rough figure as the alkalinity of hops vary from batch to batch. Also notes that acidifying casting wort 4-4.5 for heavily dry hopped beers might be a good idea for yeast health.

I did a little follow up on probrewer and seen some references of acidifying casting wort to 4.7.

 

[VikeMan]

In the podcast, he mentions 1lb dryhops per bbl of wort could raise finished beer pH by .1. This is a rough figure as the alkalinity of hops vary from batch to batch.

The hops may vary, but so will the beer's own pH and buffering capacity from recipe to recipe. (i.e. the hops are not the only variable.)

Also notes that acidifying casting wort 4-4.5 for heavily dry hopped beers might be a good idea for yeast health.

Are you sure this wasn't in reference to sours? Anyway, it seems odd that this would be "for yeast health" when they're talking just specifically about heavily dry hopped beers. What are the supposed ill-effects to the yeast of not doing it, and how would those health affects be unique to heavily dry hopped beers? i.e. fermentation is normally finished before (traditional) dry hopping.

I did a little follow up on probrewer and seen some references of acidifying casting wort to 4.7.

Even 4.7 seems pretty low. That's just about knocking on the door of pre-acidification for a wort intended to be kettle soured.

You can also (i.e. instead) add acid to the finished beer (post dry hop), once you see where the pH lands.

 

[aeviaanah]

The hops may vary, but so will the beer's own pH and buffering capacity from recipe to recipe. (i.e. the hops are not the only variable.)

That's true, good point. The .1 change is just a rough estimate.

Are you sure this wasn't in reference to sours? Anyway, it seems odd that this would be "for yeast health" when they're talking just specifically about heavily dry hopped beers. What are the supposed ill-effects to the yeast of not doing it, and how would those health affects be unique to heavily dry hopped beers? i.e. fermentation is normally finished before (traditional) dry hopping.

This was not in reference to sours, IPAs and dry hopping. He is claiming viability and vitality are affected with the dryhop additions. Also that diacetyl (due to yeast health and pH range) could be an issue. From what I understand, in a typical beer, the yeast change the pH from 5.2-5.4 down to the less stressful 3.8-4.5. He made a good point that yeast haven't evolved to deal with these higher pH ranges due to dry hopping being relatively new. In other words if the dry hops aren't added the pH wouldnt rise and the stresses at the pH ranges wouldn't exist.

Even 4.7 seems pretty low. That's just about knocking on the door of pre-acidification for a wort intended to be kettle soured.

You can also (i.e. instead) add acid to the finished beer (post dry hop), once you see where the pH lands.

I agree although I took his word for it for the pale ale we did yesterday. 170 gallons! Ran out of lactic acid but I was to get it down to 4.75.

I understand i can acidify the final beer pH and I could do that for shelf life, flavor profile etc. I interpret his argument to be based around yeast health during fermentation (and planning for harvesting and subsequent pitches) BEFORE the damage is done due to the high pH.

What issues do you see with pre acidifying 4.1-4.7 if the yeast will take it there anyway?

 

[VikeMan]

He is claiming viability and vitality are affected with the dryhop additions. Also that diacetyl (due to yeast health and pH range) could be an issue. From what I understand, in a typical beer, the yeast change the pH from 5.2-5.4 down to the less stressful 3.8-4.5. He made a good point that yeast haven't evolved to deal with these higher pH ranges due to dry hopping being relatively new. In other words if the dry hops aren't added the pH wouldnt rise and the stresses at the pH ranges wouldn't exist.

But, I've never seen any science that says sacch yeast strains are particularly "stressed" by a pH of 5.2. And plenty of fermentations (maybe most) start around there. But even if we stipulate "5.2 pH is stressful," keep in mind that by the time you add dry hops, an ale fermentation is typically down to around the low 4's.

What issues do you see with pre acidifying 4.1-4.7 if the yeast will take it there anyway?

The risk is that the yeast could take the pH too low, because they are going to excrete the same organic acids regardless of where the pH starts. That said, the pH impact is mitigated by the logarithmic nature of pH change.

 

[aeviaanah]

But, I've never seen any science that says sacch yeast strains are particularly "stressed" by a pH of 5.2. And plenty of fermentations (maybe most) start around there. But even if we stipulate "5.2 pH is stressful," keep in mind that by the time you add dry hops, an ale fermentation is typically down to around the low 4's.



The risk is that the yeast could take the pH too low, because they are going to excrete the same organic acids regardless of where the pH starts. That said, the pH impact is mitigated by the logarithmic nature of pH change.

What is the risk and what would you consider to be too low?

Have you had a chance to listen to the episode?

 

[aeviaanah]

Double post

 

[VikeMan]

What is the risk and what would you consider to be too low?

The risk is that the beer could taste "tart" or otherwise "off" if the final pH is below normal. I can't give a number on "too low" because... What's the style? What other flavors in the particular beer might mask it (or not)? How sensitive is the drinker's palate to the additional acid?

An analogy would be to ask "how roasty is too roasty?" Or "how bitter is too bitter?"

Have you had a chance to listen to the episode?

I haven't.

Do they discuss rigorous experimental data, including final beer pH measurements, associated with acidifying the cast wort pH down to 4.0? If so, I may give it a listen. Please consider the previous sentences carefully before you answer in the affirmative. Thanks!

If they don't, I probably won't.

 

[aeviaanah]

The risk is that the beer could taste "tart" or otherwise "off" if the final pH is below normal. I can't give a number on "too low" because... What's the style? What other flavors in the particular beer might mask it (or not)? How sensitive is the drinker's palate to the additional acid?

An analogy would be to ask "how roasty is too roasty?" Or "how bitter is too bitter?"



I haven't.

Do they discuss rigorous experimental data, including final beer pH measurements, associated with acidifying the cast wort pH down to 4.0? If so, I may give it a listen. Please consider the previous sentences carefully before you answer in the affirmative. Thanks!

If they don't, I probably won't.

I do not believe they are discussing it in a manner you would like to hear