Single infusion mash and ph

[Blarneybrew]

AAmylase is optimal at 6.7-7.0 pH says Wikipedia. If you are doing a single infusion mash in the alpha range why lower the pH for optimal beta amylase range?

 

[MachineShopBrewing]

There are tons of other reactions going on inside a mash besides A-amylase activity. Plus you have to think about boil pH/hop utilization/flavor and pH going into the fermentor.

I would say that the best brewing scientists have gone with 5.2-5.6 as the preferred range for a reason.

 

[Blarneybrew]

I'm sure they have. I'm just querying for a better understanding

 

[MachineShopBrewing]

I'm sure they have. I'm just querying for a better understanding

Then I would look into all of the other reactions going on in the mash to help you understand it better. It is a pretty complex process.

 

[Blarneybrew]

Then I would look into all of the other reactions going on in the mash to help you understand it better. It is a pretty complex process.

I probably will once I know them. Most often I find that asking a question leads to more questions. Of course it's sometimes dependent on who is patient enough to explain them well enough to beg further questioning

 

[slarkin712]

I'm just an amateur, but I'll give a couple of top of mind reasons. First, the buffer system, i.e. the system that controls the pH of the mash, is mostly influenced by the contributions from the grain. In a very general sense, water mixed with grain in typical mash ratios will stabilize from 5.2-5.6 at room temperature. So, typically you are not lowering the pH to get into the Beta amylase range, it naturally settles there. Secondly, mash pH above 5.6, and certainly above 6.0 will extract tannins from the grains, which give an unpleasant astringency. There many other factors such as hop utilization, flavor effects,etc., but I would surmise that tannin extraction would be the main flavor driven reason.

 

[Blarneybrew]

pH and tannins? Wow. I thought I would have read this somewhere by now. Interesting.

 

[ResumeMan]

pH and tannins? Wow. I thought I would have read this somewhere by now. Interesting.

Well as I understand it, in the mash, you're not that likely to extract tannins whatever you do, as the buffering capabilities of the grist will keep the pH below the extraction level, although you could have a pH that is high enough to throw things out of whack in other ways.

But where pH and tannins really comes into play is in the sparge. If you're using fly sparging, by the end of the sparge most of the buffering components will have been washed out. And so if the pH and alkalinity of the sparge water is too high it can make the grain bed pH drift up to the point of tannin extraction.

I don't have a lot of expertise on that part, as I batch sparge, and it's my understanding that with a single-batch sparge, the pH will pretty much never be able to drift too high.

 

[Blarneybrew]

What if you sparge using the existing wort? Wouldnt that make it pretty near impossible to extract tannins?

I still have a hard time conceptualizing three vessel brewing and why there are so many variations of it. I need to see them at in one neatly made youtube video

 

[ResumeMan]

You need to sparge with fresh water, not wort - that's the whole point of the sparge, to rinse the sugars out of the grist.

 

[jcmcdowell]

Gordon Strong does a good job of explaining ph objectives and water issues in his book. Great book overall.

-Sparge water is ideally lower the ph 6 or else it can extract tannins and add astringency to the beer.
-Mash is ideally in the 5.2 to 5.6 range
-Dark grains/crystal/cara help lower the mash PH
-mash ph in the proper range helps conversion and can increase extraction of the sugars from the grain.
-gypsum does not lower water ph- only with grain (i.e. not good with sparge water)
-phosphoric acid is Gordon Strongs 'go to' addition for lower water ph.
-calcium is important for both the mash and the yeast activity.

Still learning though....

 

[jcmcdowell]

What if you sparge using the existing wort? Wouldnt that make it pretty near impossible to extract tannins?

recirculating the wort, either manually or by pump is the 'vorlauf'. It helps increase extraction and uses the grain bed as a filter to 'clean up' the wort before moving to the boil.

After the vorlauf you can sparge or not sparge depending on your objectives for the gravity of beer/ease of brewing (no sparge-more sugar in less water, but less efficient) or sparge (varying levels of increased volume and efficiency)

Dave Millers's Homebrew Guide is a good place to start as well.

 

[Blarneybrew]

But if you're rinsing with 168F wort. I mean with fresh water you can only sparge a certain volume and then you run out. Surely you can't be losing much if you rinse with hot wort twice as long as you would water?

Oops, incoming posts. I should have quoted you

 

[Blarneybrew]

Strong and Miller. Got it. I enjoyed Charlie P's book. For quick primer. Old one I had. With porn stasches and hair

 

[jcmcdowell]

But if you're rinsing with 168F wort. I mean with fresh water you can only sparge a certain volume and then you run out. Surely you can't be losing much if you rinse with hot wort twice as long as you would water?

Oops, incoming posts. I should have quoted you

All kinds of issues with that...

For starters longer times at higher temps can darken color and add more astringency, dryness via dark grains.

I have never heard of brewing efficiency being as good without a sparge.

 

[slarkin712]

Here's a quote from an expert on the bru'n water knowledge page:

"The pH of the mash influences a number of factors in brewing including; fermentability, color, clarity, and taste of the wort and beer. A slightly acidic mash pH of between 5.2 and 5.8 (measured at room-temperature) improves the enzymatic processes during mashing. The lower end of that range produces more fermentable wort and thinner body. The lower end of that range also produces better extraction efficiency, lighter color, better hot break formation, and the beer is less prone to form haze. Allowing the mash pH to fall below this lower boundary increases the potential to solubilize excess protein into the wort (De Clerck, 1957). The upper end of that range produces less fermentable wort and more body (Briggs et. al., 1981). Tailoring the mash pH helps a brewer create the wort character desired for the finished beer. In most cases, narrowing the target mash pH range to between 5.3 and 5.5 is recommended.

Minor increases in wort or beer pH can create problems in the finished beer. Increased wort and beer pH makes the beer’s bittering perception more ‘coarse’ and less favorable. The isomerization of alpha acids during the boil is increased slightly as wort pH increases, which may add to the coarseness. Increased pH in wort and the finished beer slows the reduction and removal of diacetyl from beer during maturation. During mashing, a pH greater than 6.0 can leach harsh-tasting silicates, tannins, and polyphenols from the grain into the wort (Briggs et. al., 1981). Adjusting sparge water pH to between 5.5 and 6.0 helps avoid raising the mash pH above 6.0 during sparging."

Now, I'm not sure this is the most up to date mash pH information, but general mash pH theory should follow this. I couldn't find anything with a more straight forward explanation in the Palmer/Kaminski "Water" book.

 

[Blarneybrew]

Here's a quote from an expert on the bru'n water knowledge page:

"The pH of the mash influences a number of factors in brewing including; fermentability, color, clarity, and taste of the wort and beer. A slightly acidic mash pH of between 5.2 and 5.8 (measured at room-temperature) improves the enzymatic processes during mashing. The lower end of that range produces more fermentable wort and thinner body. The lower end of that range also produces better extraction efficiency, lighter color, better hot break formation, and the beer is less prone to form haze. Allowing the mash pH to fall below this lower boundary increases the potential to solubilize excess protein into the wort (De Clerck, 1957). The upper end of that range produces less fermentable wort and more body (Briggs et. al., 1981). Tailoring the mash pH helps a brewer create the wort character desired for the finished beer. In most cases, narrowing the target mash pH range to between 5.3 and 5.5 is recommended.

Minor increases in wort or beer pH can create problems in the finished beer. Increased wort and beer pH makes the beer’s bittering perception more ‘coarse’ and less favorable. The isomerization of alpha acids during the boil is increased slightly as wort pH increases, which may add to the coarseness. Increased pH in wort and the finished beer slows the reduction and removal of diacetyl from beer during maturation. During mashing, a pH greater than 6.0 can leach harsh-tasting silicates, tannins, and polyphenols from the grain into the wort (Briggs et. al., 1981). Adjusting sparge water pH to between 5.5 and 6.0 helps avoid raising the mash pH above 6.0 during sparging."

Now, I'm not sure this is the most up to date mash pH information, but general mash pH theory should follow this. I couldn't find anything with a more straight forward explanation in the Palmer/Kaminski "Water" book.

That's great. Thanks!