Can't find a balance between ph and bicarb

[pmoneyismyfriend]

Having a difficult time trying to strike a balance with my ph and bicarb.
When adjusting ph with acid I deplete my bicarb, then when adjusting to regain the desired bicarb level, my ph gets thrown out of whack. The profile is good and there are no other additions necessary, just acid to bring my ph into line. Using lactic and or phosphoric.

Apologies if this has been discussed somewhere else in the forum

 

[Yooper]

Having a difficult time trying to strike a balance with my ph and bicarb.
When adjusting ph with acid I deplete my bicarb, then when adjusting to regain the desired bicarb level, my ph gets thrown out of whack. The profile is good and there are no other additions necessary, just acid to bring my ph into line. Using lactic and or phosphoric.

Apologies if this has been discussed somewhere else in the forum

Just realize that there is NO desirable amount of bicarbonate. Actually, there is I suppose- and that is 0. So you never want to add bicarbonate, unless you have a pH that is too low (which is rare and would only happen if you're using distilled or RO water and making a stout).

 

[pmoneyismyfriend]

For different profiles, there are different levels of bicarb. The profile I am following is Munich Boiled. The question is, then, why is there a target level for bicarb, if any amount is undesirable?

 

[Silver_Is_Money]

Bicarb is only needed if you discover a need to upwardly adjust your mash pH. The most typically accepted mashing pH range (the range wherein the Alpha and Beta Amylase enzymes which facilitate starch conversion are found to be most active) spans from 5.2 to 5.6, with a midpoint of 5.4. Technically, upward adjustment is only needed if you measure a mash pH below 5.2. That said, there are some arguments that can be made for targeting mash pH's closer to 5.5 for the some of the darker beer styles (which by the acidic nature of their dark malts are ironically the styles most likely to have the potential to dough in on the low side of, or even below the low end of the nominally ideal 5.2 to 5.6 target pH range).

The answer as to why does alkalinity (bicarbonate) show up in most of the famous brewing locations regional water profiles is simply that it is inherent to most naturally sourced surface and underground waters. The key thing to understand is that bicarbs inherent presence in most regional brewing water sources is emphatically not to be construed as an indicator that it is inherently desired for good brewing results.

https://mashmadeeasy.yolasite.com/

 

[ajdelange]

When adjusting ph with acid I deplete my bicarb, then when adjusting to regain the desired bicarb level, my ph gets thrown out of whack.

Bicarbonate is an alkali with respect to mash pH. When you add an acid to an alkali the alkali is neutralized (depleted) and the pH goes down. When an alkali is added it neutralizes acid and the pH goes up. What you are seeing is exactly what one expects to see.

The profile is good and there are no other additions necessary, just acid to bring my ph into line. Using lactic and or phosphoric.

Probably not. I don't know how all the spreadsheets and calculators handle profiles but I do know (or think I know) how Brun water handles it and I suspect some of the others do essentially the same thing. The author decides somehow how much calcium, magnesium, sodium, sulfate and chloride he thinks the water of Bad Schimmel should have. But when he adds the electric charges of all these ions up he finds a healthy net positive charge. As any real water is neutral he has to add some anion to acheive balance, As sulfate and chloride are already at desired levels he can't add more of those. Given this and knowing that most waters contain at least some bicarbonate he decides to balance out the charge with bicarbonate ions. As bicarbonate ions only have a charge of 1 mEq/mmol NaHCO3 added at pH 8.3 the water profile thus specified is only balanced at pH 8.3 and can thus exist only at pH 8.3. In other words, a mineral profile that contains bicarbonate (or any other weak acid) is only valid at a certain pH. In Brun water that pH is 8.3. It is, of course, entirely possible to account for pH properly but none of these programs that I am aware of do so. If they did they would require you to enter the source water pH and dilution water pH and tell you the pH of the solution that results when you add minerals. The usual advice is to simply ignore the bicarbonate. I broaden that to say you should take any specified profile with a grain of salt. Using a profile may make the most authentic pilsner but you can make a better pilsner by using a profile quite different from Pilsn's. This is a case where you want to put more in that the Pilsn water naturally provides. In other cases you want to take stuff out. In particular the bicarbonate (Munich would be example of that). It isn't enough to know what is in Munich water. You must know what the brewers did to it before they brewed with it. In the case of Munich this involves taking out as much bicarbonate as possible and accepting the attendant calcium loss.

 

[pmoneyismyfriend]

holy **** you guys are smart. good stuff. thank you