Baking Soda and Lactic Acid in Same Mash

[RPh_Guy]

This is not the case

It's not true that calcium precipitates with carbonate/bicarbonate during the boil?

 

[Gnomebrewer]

With lower calcium the beer would not ferment as fully or quickly, the yeast struggling due to insufficient free ammino nitrogen produced during the mash aided by calcium. It would not clear in the same way or at the same rate, a haze from oxalates and other matters that would be deposited in the mash with calcium as well as yeast in suspension that cannot readily flocculate due to lack of calcium in their cell walls.

Most of my ales have 50 to 80ppm Calcium. They typically ferment to FG in three to five days and drop very clear (without gelatine). I've successfully brewed lagers with 30ppm Calcium, which also have no problems attenuating or dropping clear. Maybe I'm just lucky. Maybe Pilsen and Munich breweries are, too.

 

[mabrungard]

The need for calcium in brewing water is overblown. While its fairly beneficial and benign in ale brewing, it can be a detriment in lager brewing since it interferes with lager yeast metabolism. In addition, elevated calcium can cause premature yeast flocculation and that can delay or stop fermentation.

I agree that calcium is not precipitated as calcium carbonate in the boil. The chemistry is not favorable for that.

Regarding lactate perception in beer, the dose would have to be fairly high for most tasters to perceive it. It is not true that lactic acid usage is going to produce undesirable flavor compared to phosphoric acid. The water alkalinity would have to be fairly high for lactic acid not to produce a decent beer.

 

[cire]

Does this mean you've brewed the same beer & same process with lower calcium?

Not for thirty or more years. It shouldn't necessary to learn essentials over and over again.

 

[RPh_Guy]

The calcium that is not used by phosphate and oxalate precipitation, ect, is still mostly lost in process via trub/hot-cold break and sparge/boil.

Let me get this straight, ~70% (why it's a percentage, I don't understand either) of calcium is lost to binding proteins and precipitating phosphate and oxalate... but not carbonate? This happens regardless of the other ions in the water?

What's all this nonsense I hear about "temporary hardness" then?

Not for thirty or more years. It shouldn't necessary to learn essentials over and over again.

One day 30+ years ago you decided to triple the minimum calcium level (without changing other aspects of your process) and suddenly your beer fermented faster and dropped clear faster? And you've never reduced calcium since that day? Am I following?

Regarding lactate perception in beer, the dose would have to be fairly high for most tasters to perceive it.

Maybe that's true and I'm just one of the unlucky few who do taste it.
My tap water has 99ppm bicarbonate and I can't brew pale beers without tasting the lactic acid needed to hit proper mash pH.

It is not true that lactic acid usage is going to produce undesirable flavor compared to phosphoric acid.

Fact: The average tasting threshold for phosphoric acid is much higher than lactic acid.

Beyond that I can only say that I've seen more people prefer phosphoric. There's an exbeeriment that produces non-significant results but the correct respondents preferred the phosphoric. I've also seen several here on HBT that prefer phosphoric because of the taste, and none that prefer lactic.

I don't doubt most people don't notice a difference or the difference is covered up by a boatload of hops. YMMV.
Back to my original statement, I don't think adding lactate beyond what's needed for hitting mash pH with lactic acid is something I'd recommend. But hey, it's all good if you folks want to try it in your beer.

 

[cire]

?

One day 30+ years ago you decided to triple the minimum calcium level (without changing other aspects of your process) and suddenly your beer fermented faster and dropped clear faster? And you've never reduced calcium since that day? Am I following?

I've been brewing since 1963. It took many years searching to learn what to do and how to do it. The final searches have yet to happen, but as far as calcium levels are concerned, they have long since come to an end and I'll never waste good grain and hops to go back.

When brewing to replicate lagers made in low mineral water areas, then lower mineral water is used. If I wish to make a traditional ale, then calcium level are between 100 and 200 mg/L. To make a beer to be entered in BJCP judged competitions a low calcium level is required, but in those cases, others can do the drinking.

 

[Silver_Is_Money]

It seems to me that the brewing philosophy of the UK is to generally target a ballpark of 100-200 mg/L of calcium, whereas in the USA we generally target about half of this amount.

 

[mabrungard]

Fact: The average tasting threshold for phosphoric acid is much higher than lactic acid.

Agreed. The average taster can perceive lactate at around 400 ppm. Super-tasters are likely to taste it at lesser concentrations. Phosphate is abundant in wort and adding more phosphate ions via acid addition is not going to significantly alter the taste.

The problem is that you are making an absolute statement about the use of lactic acid that is not valid when its final concentration is below most taster's threshold. Then the acidifying and taste impacts of either acid are equivalent...by which I mean imperceptible.

 

[bierhaus15]

The need for calcium in brewing water is overblown. While its fairly beneficial and benign in ale brewing, it can be a detriment in lager brewing since it interferes with lager yeast metabolism. In addition, elevated calcium can cause premature yeast flocculation and that can delay or stop fermentation.

The studies I've seen regarding Ca being a detriment to lager fermentation are in the context of replacing Mg with Ca, of which Ca wort levels were in excess of 500 ppm. Under that amount, no detrimental effect was noted given there was appropriate Mg available, which should be sufficient using all malt worts. I've heard of specific lager yeasts being sensitive to high Ca levels, but those were used to ferment mostly adjunct beers (sorghum/rice). ABI and most industrial German breweries are still targeting Ca wort levels above 40 ppm for lager fermentations.

Also, latest info on premature yeast flocculation shows it has more to do with fungal infection of barley (fusarium) than calcium alone. While Ca is needed for the phenomenon to occur, Ca alone is not responsible.

 

[RPh_Guy]

The problem is that you are making an absolute statement about the use of lactic acid that is not valid when its final concentration is below most taster's threshold.

That's not my intention. I totally agree it's fine if its below taste threshold.
I simply don't want to use (or recommend) a water profile that may push lactate above taste threshold.

If I wish to make a traditional ale, then calcium level are between 100 and 200 mg/L.

Normally I hit around 50ppm Ca. I'll try ~150ppm Ca in my next few brews and see what changes.
What could go wrong?

This is my normal approach and I'm glad that it is yours also. Reaffirms that my problem is probably not water related. I'll go with the what @RPh_Guy suggested initially. That puts me at close to 100ppm calcium.

Best of luck to you!

 

[ajdelange]

It's not true that calcium precipitates with carbonate/bicarbonate during the boil?

If bicarbonate has carried over to the boil then yes but most of that is going to have been driven off in the HLT and mash tun. pH reduction in the kettle is, I believe, mostly due to precipitation of calcium with phosphate (this also happens in the mash) and protein.

 

[Silver_Is_Money]

If the OP does decide to add baking soda and then neutralize it with lactic acid, he might be glad to hear that (for all practical purposes) 1 mL of 88% Lactic acid will fully neutralize 1 gram of baking soda. This fortuitously simple 1:1 ratio relationship makes neutralizing the baking soda rather easy to accomplish for the specific case of using 88% lactic acid.

Answering his specific questions raised in his initial post:

Despite it's not being something that is commonly done, there is (for most cases) nothing wrong with adding baking soda to introduce sodium ions, followed by neutralizing the bicarbonate ion component with an acid of your choosing. The only possible negative I can think of might be if the neutralizing acid of choice is lactic acid, and the required lactic acid addition exceeds its flavor threshold. This should be a rare happenstance.

The 1 ppm of magnesium can be fully ignored. There is sufficient magnesium inherent within the grist itself such that additional magnesium addition can always be ignored. At some juncture of additional magnesium addition it will begin to make your beer taste nasty (this will perhaps occur at ~20-30 ppm Mg++ and above), and there is no level of addition for which it will ever be of a net positive flavor benefit. Therefore, add Epsom Salt (MgSO4.7H2O) in moderation only if it proves to be the last remaining option by which to raise sulfate ions to your desired target.

 

[ajdelange]

If the OP does decide to add baking soda and then neutralize it with lactic acid, he might be glad to hear that (for all practical purposes) 1 mL of 88% Lactic acid will fully neutralize 1 gram of baking soda. This fortuitously simple 1:1 ratio relationship makes neutralizing the baking soda rather easy to accomplish for the specific case of using 88% lactic acid.

Bicarbonate is not fully neutralized at mash pH.

The amount of lactic acid required to offset a particular bicarbonate addition depends on the target pH. I have published curves here in the recent past which show how much is required for a particular pH.

The only possible negative I can think of might be if the neutralizing acid of choice is lactic acid, and the required lactic acid addition exceeds its flavor threshold.

How is lactic different from say citric in this regard?

 

[Silver_Is_Money]

How is lactic different from say citric in this regard?

The same potential flavor impact warning would apply for citric acid. But the fortuitous 1:1 relationship for the purpose of neutralization most likely would not apply (wherein admittedly I have never thought of using citric acid, so I have not calculated its neutralization ratio/relationship with respect to baking soda).

 

[Silver_Is_Money]

Bicarbonate is not fully neutralized at mash pH.

AJ, how far off would my ballpark of 1 mL of 88% lactic acid to neutralize 1 gram of baking soda be for the case of a target mash pH of 5.4? How much 88% lactic acid is actually required for this target mash pH if 1 gram of baking soda was added?

I like to work with ballpark generalizations whereby you prefer to work with highly precise specifics. Is the relationship of 1 mL to 1 gram in the ballpark, or completely out of the ballpark?

 

[Big Monk]

AJ, how far off would my ballpark of 1 mL of 88% lactic acid to neutralize 1 gram of baking soda be for the case of a target mash pH of 5.4? How much 88% lactic acid is actually required for this target mash pH if 1 gram of baking soda was added?

You have the tools!

Calculate the Q value for Lactic acid at 5.4 (or any pH for that matter) and then calculate the Q value for NaHCO3 at that same pH.

I think what I may do is clean up the original water troubleshooter/voltmeter code from our big thread last year and distribute it for those who can’t access or use A.J.’s brewing functions sheet

 

[Silver_Is_Money]

You have the tools!

I'm still hampered by my use of LibreOffice Calc. Would you provide the solution for me?

 

[Big Monk]

I'm still hampered by my use of LibreOffice Calc.

The original troubleshooter should work great in libreoffice.

 

[Silver_Is_Money]

For the benefit of the forum members, wouldn't it simply be more advantageous to all of us if answers were provided rather than evasions? We are trying to benefit the OP here. If he added 3 grams of baking soda for its sodium content, and then added 3 mL of 88% lactic acid to neutralize it, would his resulting mash pH be so disrupted by this simple ballpark ratio as to destroy his beer?

 

[Big Monk]

For the benefit of the forum members, wouldn't it simply be more advantageous to all of us if answers were provided rather than evasions? We are trying to benefit the OP here. If he added 3 grams of baking soda for its sodium content, and then added 3 mL of 88% lactic acid to neutralize it, would his resulting mash pH be so disrupted by this simple ballpark ratio as to destroy his beer?

Why don’t you perform the calcs and post them here. If what you are saying is that you can’t, then I’d be happy to do them and post them here.

 

[Silver_Is_Money]

I posed this baking soda to lactic acid question to the forum roughly 2 years ago and back then AJ concluded in answering my query that it was right close to 1 mL of 88% lactic acid to 1 gram of baking soda. Should I simply point to that thread? Have things radically changed in 2 years?

 

[Silver_Is_Money]

And I believe that Braukaiser once stated the ratio relationship at 0.991 grams baking soda to 1 mL of 88% lactic acid. Close enough to 1:1 in my book for ballparking it.

 

[ajdelange]

.

 

[ajdelange]

For the benefit of the forum members, wouldn't it simply be more advantageous to all of us if answers were provided rather than evasions? We are trying to benefit the OP here.

There are evidently different opinions as to what "benefit" means. Some feel that he benefits by simply being given the answer without requiring any thought on his part. This avoids any potential for neuron damage. Others evidently feel that the spirit of the forum "In depth technical threads related to the biology and chemistry of home brewing." suggests that he will benefit more if he is nudged into learning something.

 

[Big Monk]

I posed this baking soda to lactic acid question to the forum roughly 2 years ago and back then AJ concluded in answering my query that it was right close to 1 mL of 88% lactic acid to 1 gram of baking soda. Should I simply point to that thread? Have things radically changed in 2 years?

Or you could confirm it for yourself and for others and post it here. It’s a few lines of code in an excel spreadsheet.

I’m honestly not trying to bust your chops or deprive the OP.

I’d do it but I have limited access to my computer today.

 

[Silver_Is_Money]

Or you could confirm it for yourself and for others and post it here. It’s a few lines of code in an excel spreadsheet.

I’m honestly not trying to bust your chops or deprive the OP.

I’d do it but I have limited access to my computer today.

OK, let's look at this from purely a chemical reaction perspective:

The players:

NaHCO3 (baking soda) : molceular weight = 84.00661 g/mol
CH3CH(OH)COOH (Lactic Acid, alternately HC3H5O3): molecular weight = 90.07794 g/mol

The reaction:

NaHCO3 + CH3CH(OH)COOH → CH3CH(OH)COONa + H2O + CO2

Which can alternately be written if desired as:

NaHCO3 + HC3H5O3 → NaC3H5O3 + H2O + CO2

From this we can see that lactic acid is monoprotic, liberating only 1 H+ in exchange for 1 Na+

And therefore, with that behind us, we may proceed as follows:

Weight of 1 mL 88% lactic acid = 1.2092 grams

1 mL of 88% lactic acid contains 1.2092 grams x 0.88 = 1.064096 grams of pure lactic acid

Stoicometrically (for 1 mL of 88% lactic acid) the left side of the reaction on a weight relationship basis becomes:

1.064096/90.07794 * 84.0061 = 0.99237 grams NaHCO3 (baking soda)

Thus we may conclude that:

1 mL of 88% lactic acid will neutralize 0.99237 grams of backing soda provided that the reaction goes to completion, which it eventually should if all of the generated CO2 evolves out of the solution as a gas. There will be of course some portion of CO2 which will not be liberated from solution as a gas, and as such, some degree in which the reaction can potentially be driven in reverse (until such time as nigh on all CO2 is released from the system as a gas).

But why must we put the OP and the general audience at large through this level of chemistry lesson exercise? And lastly, would you have approached it from this perspective?

 

[ajdelange]

But why must we put the OP and the general audience at large through this level of chemistry lesson exercise? And lastly, would you have approached it from this perspective?

Because this is the Brewing Science forum to which people come, presumably, to learn something about brewing science. There are plenty of other fora in which the "I don't care how it works, just tell me what to do" type of questions can be fielded.

Given that we are where we are let's discuss the chemistry correctly:

If we add m moles of NaHCO3 to water two things happen
1) The NaHCO3 dissociates into Na+ ions and HCO3- ions
2)Some of the HCO3- ions give up a proton (H+) and in so doing convert to CO3--
3)Some of the HCO3- ions take up a proton and in so doing convert to H2CO3
4)Most of the H2CO3 becomes CO2 gas and water.

m NaHCO3 + ? H+ <--> m Na+ +m*a2 CO3-- + m*a1 HCO3- + m*a0 H2CO3 <--> m Na+ +m*a2 CO3-- + m*a1 HCO3- + m*a0 CO2 + m*a0 H2O

a0, a1 and a2 are three positive numbers that sum to 1. Thus they represent, respectively, the fractions of the CO moieties that, at the conclusion of the reaction, reside in, respectively, carbonic acid or carbon dioxide, in bicarbonate ion and in carbonate ion.

When we started the charge on the NaHCO3 is 0 made up of m + charges on the sodium ions and m - charges on the bicarbonate. When we are finished there are still m + charges on the sodium but 2*m*a2 on carbonate and m*a1 on bicarbonate. Thus the charge on the carbo moieties has changed from -m to -m*(2*a2 + a1) i.e. by m*(a1 + 2*a2 -1). a0, a1 and a23 depend on the pH at which the mixture of bicarbonate and lactic acid finally arrives. At mash pH a1 is a small number and a1 smaller still thus the charge on bicarbonate has become approximately 1 - a1 less negative. Thus the equation for the sodium bicarbonate is

m NaHCO3 + m*(1 - a1 - 2*a2) H+ <--> m Na+ +m*a2 CO3-- + m*a1 HCO3- + m*a0 CO2 + m*a0 H2O

Clearly the m*(1 - a1 - 2*a2) moles of H+ ions (protons) must come from the lactic acid. If n moles of lactic acid be added to water the following reaction takes place

n HLac <--> n*b1 H+ n*b1 Lac- + n*b0 Hlac.

Here b1 and b0 are again fractions of the totality of Lac. b0 + b1 = 1 and again the b's depend on the final pH of the mix. Note that at mash pH b1 is close to, but not equal, to 1. Thus to neutralize (where "neutralize" means to bring to some desired pH, that being the pH from which the a's and b's are calculated, we require that n*b1 = m*(1 - a1 - 2*a2) meaning that

n = m*(1 - a1 - 2*a2)/b1

moles of lactic acid are required to "neutralize" m moles of bicarbonate. As b1 is close to 1 and as a1 and a2 are small at mash pH it is approximately true that one mole of lactic acid "neutralizes" 1 mole of NaHCO3. Using the molecular weights of NaHCO3 along with the density of HLac solutions of various strengths we can work out the volume of HLac solution of given concentration required to neutralize a gram of NaHCO3.

Note: This may seem a bit complicated at first but we sumplify it by wrtiting spreadsheet functions (or using spreadsheet cells) to calculate Qcarb(pH) and Qlac(pH) where each equals the charge on the anions of the respective acids at the passed value of pH. Assuming we want pHz we know that the charge on the carbo ions changes from -m to m*Qcarb(pHz) i.e. it increases by m*(1 + Qcarb(pHz)) and that the charge on the lactic anion changes from 0 to n*Qlac(pHz) i.e. decreases by -Qlac(pHz). The Q's, representing anion charges, are negative numbers. Thus we immediately calculate

n = -m*((1 + Qcarb(pHz))/Qlac(pHz)

The use of Q's makes the calculations for problems of this nature (of which there are many in brewing) very simple.

Q is computed from pHz using the method given in the Sticky on carbonates.

...provided that the reaction goes to completion, which it eventually should if all of the generated CO2 evolves out of the solution as a gas. There will be of course some portion of CO2 which will not be liberated from solution as a gas, and as such, some degree in which the reaction can potentially be driven in reverse (until such time as nigh on all CO2 is released from the system as a gas).

It should be clear from the foregoing that the reaction will not complete. At mash pH some 8% or so of the added bicarbonate will remain as bicarbonate.

 

[ajdelange]

The last sentence in the last post is a bit disingenuous as it assumes that no CO2 escapes the solution which, of course, it does. It would be more accurate to say that there will always be some bicarbonate in solution (in fact if you don't add any the air will add some and when you carbonate your beer you add quite a bit) and thus the reaction does not complete. How much of the bicarbonate that you add remains will depend on a lot of things like time. If you wait long enough (a very long time) a sodium bicarbonate solution will convert to a sodium carbonate solution with very little bicarbonate as the pH will be high: 2NaHCO3 ---> H2O + CO2 + Na2CO3. This is how baking soda makes, e.g., pancakes rise.