How does the mash pH affect the final taste and pH of the beer?

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Elysium

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Just been listening to Jamil and Palmer's show about “why you wanna adjust your water” and they talk about pH in the beer (in the final product).

This is still something I dont fully understand.
I have managed to learn/understand that pH (5.2-5.6) at mashing and boiling is important. During mashing because the enzymes prefer a specific temp and pH and at boiling because it affects the hop extraction tastes.

Now......what's the story with the final pH of the beer? Is the pH of the wort in the brew kettle the same pH that my final beer will have?

Is there a way to understand what kind of taste profile (or what is emphasized or diminished) through the different pH levels in the final product? Is there an article or a chart for that?

I am wondering if I should measure the pH of my final beer and I am wondering if it will be the same as the mash pH was?
 
Yeast activity does further reduce the pH of beer. In some respects, the final beer pH is relatively independent of the wort pH. The yeast species has a stronger influence on how low the beer pH is.
 
Now......what's the story with the final pH of the beer? Is the pH of the wort in the brew kettle the same pH that my final beer will have?

No! One of the underappreciated benefits of owning a pH meter is that you can tell within a few hours, well before there are visible signs, that your ferment is healthy and underway. There should be a pH drop of a few tenths early on. pH will continue to trickle down during the course of the ferment depending on the beer. With ales it will usually go below 4.5. With lagers it will be closer to 4.5 and sometimes even a bit higher.

Is there a way to understand what kind of taste profile (or what is emphasized or diminished) through the different pH levels in the final product? Is there an article or a chart for that?

pH control in the mash tun has the major effect on beer flavor. Someone put it quite well when he said that "All the flavors are brighter" after he started paying attention to mash pH. Some brewers do adjust the pH of the final beer. Which acid you use to do this will have an effect on flavor. Clearly using lactic as opposed to phosphoric will have a more pronounced flavor effect.

I am wondering if I should measure the pH of my final beer and I am wondering if it will be the same as the mash pH was?

Yes you should but you should also measure it as fermentation progresses. Or at least you should do this until you have a handle on what to expect in this regard. If you keep extensive notes on your brews then I think that pH definitely belongs in those notes.

As noted above beer pH should be well below mash pH.
 
No! One of the underappreciated benefits of owning a pH meter is that you can tell within a few hours, well before there are visible signs, that your ferment is healthy and underway. There should be a pH drop of a few tenths early on. pH will continue to trickle down during the course of the ferment depending on the beer. With ales it will usually go below 4.5. With lagers it will be closer to 4.5 and sometimes even a bit higher.



pH control in the mash tun has the major effect on beer flavor. Someone put it quite well when he said that "All the flavors are brighter" after he started paying attention to mash pH. Some brewers do adjust the pH of the final beer. Which acid you use to do this will have an effect on flavor. Clearly using lactic as opposed to phosphoric will have a more pronounced flavor effect.



Yes you should but you should also measure it as fermentation progresses. Or at least you should do this until you have a handle on what to expect in this regard. If you keep extensive notes on your brews then I think that pH definitely belongs in those notes.

As noted above beer pH should be well below mash pH.

Wouldn't hop additions have a major effect on beer pH too? After all hops are adding alpha and beta acids to the beer. So I'd imagine a very hoppy beer would have a much different pH than a less hoppy beer.
 
Although they are 'acids', those hop acids do not readily give up their protons into typical wort. I see that the typical pKa for iso-alpha acids is around 3.
 
Where are you seeing that? Were hop acid pKs around 3 then they would be 99% dissociated (would have contributed their protons) at pH 5 and it wouldn't matter whether kettle pH were 5 or 5.9. You'd only be swinging that last one percent but we know that that kettle pH has a much bigger effect than that. This and the fact that they don't contribute much to the proton surfeit of wort suggests that the pKs are closer to 5. ??
 
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