dealing with bicarbonate

[stevehaun]

My well water has high levels of bicarbonate (246 ppm). I have been using slaked lime treatment successfully for over a decade. This drops my bicarbonate level to a more manageable level (51 ppm). I still have to add acidulated malt to my lighter colored beers.
My question is this, if I simply add acid to the mash to achieve an appropriate pH, will my beers taste about the same as treating my water with slaked lime?

 

[javert]

Which acid would you add to the mash? Assuming it is going hydrochloric or sulfuric acid, it will affect the sulfate / chloride ratio and that will influence the malty / bitter taste of the beer. A quick calculation shows neutralizing with hydrochloric acid to the same 51 ppm level would increase chloride to 113 ppm and using sulfuric acid would leave 153 ppm in the best case scenario (not sure the extent to which the weak acid HSO4- and the weak base HCO3- would react).

You could mix them to keep the ratio but it would be good to know the initial concentrations of both anions in water to avoid having an excess of either one.

 

[stz]

Lime softening is fairly flavour neutral and allows you to take a known parameter and adjust it so it is in a better range. There are other ways to do this, but for you the process isn't the one you are currently doing so I can't say it'll make the same beer.

If you can accurately test mash pH on brew days you can instead use acid additions directly into the mash. You need to do this really as trying to predict it is a waste of time. The specification sheets we get from maltsters are nearly always completely off, the parameters change from delivery to delivery and we swear half the time the delivery drivers are making them up. You need to be able to test pH and calculate additions for each mash on brew day 5 minutes in with a pH meter you can calibrate for temperature.

As Javert rightly says sulpheric and hyrochloric acids are not flavour neutral and the ratios and interactions get potentially complex. We chose lactic over phosphoric as a close second for those reasons for our process as the amount we need to raise pH is only slight and lactic is easier to handle, cheaper and readily available food grade from a range of suppliers we already have accounts with. We use bicarbonate of soda to lower pH.

I'm just thankful that we don't need to reduce alkalinity as much as others and we have a good pH meter.

 

[stevehaun]

My chloride level is 2 ppm and my sulfate level is 1 ppm. I add both CaCl2 and CaSO4 to my brewing water to achieve about 50 ppm for each anion. So I do have room to use sulfuric and/or hydrochloric acid. At what point would phosphoric or lactic acid begin to affect flavor? I would like to add a single acid if possible.

 

[stz]

I've never detected it and I also know it is used successfully to bring down pH in a number of really great commercially successful breweries with no complaints.

http://braukaiser.com/wiki/index.php?title=Lactate_Taste_Threshold_experiment

This example shows that people can't really detect it under 400ppm in beer. How much you use will obviously be dependent on your grist, but you will want approx 340ppm @ 88% to bring you CaCO3 down to around 51ppm.

 

[ajdelange]

Assuming it is going hydrochloric or sulfuric acid, it will affect the sulfate / chloride ratio and that will influence the malty / bitter taste of the beer. A quick calculation shows neutralizing with hydrochloric acid to the same 51 ppm level would increase chloride to 113 ppm and using sulfuric acid would leave 153 ppm in the best case scenario

You must be in the UK. This side of the pond no one uses sulfuric or hydrochloric (except the pros). CRS is not sold here. While the ability to tweak sulfate and chloride whilst simultaneously killing bicarbonate is certainly appealing most here use phosphoric (as it is flavor neutral - see Sticky under Brewing Science) or lactic.

(not sure the extent to which the weak acid HSO4- and the weak base HCO3- would react).

No worries. Bisulfate (pKa 1.9) is a strong acid relative to bicarbonate (pHa 6.38) at mash/water treatment pH and will fizz it away.

 

[mashinary]

I personally use phosphoric acid at a strength of 10%. I have never used slaked lime, but I can't taste the acid...