Beer Forum

Anybody out there know much about mineral adjusting? I am planning a 11 gal batch of Flanders Red on Saturday, and am going to do some adjustments to my fairly soft town water. The water profile I was looking at was from wildBREWS

-------------- Ca - Mg - Na - SO4 - Cl - HCO3
My Water - 13.0 1.2 15.0 30 12.0 0
West Flander 114 10 125 145 139 370
New profile - 109 5.9 126 150 143 158

Using Beersmith, to get close to the West Flanders profile above for 11 gallons of H20, here's what I need to add:

Gypsum 7.5 gm
Table Salt 8.3 gm
Epsom Salt 2.0 gm
Calcium Chloride 0.9 gm
Baking Soda 5.0 gm
Chalk 5.0 gm

Anything seem outrageous there? The table salt number seems a bit high to me. I'm reading that West Flanders beer is high in sodium, but that doesn't mean it's right, or that the Belgian brewer doesn't try to remove it.

The listed mineral concentrations for your water are not consistent with real water by which we mean that the anion and cation charges are not equal as they must be. As you mention that it is municipal water I assume that the mineral profile is from the water authority's report to consumers. It is common for such numbers to be averages or measured at different times and this explains some of the inconsistency. Zero bicarbonate is suspicious as most water is exposed to the atmosphere somewhere in the process and this results in a bicarbonate level of at least 3.5 mg/L (at pH 7).

Given sketchy knowledge of the starting water it is, of course, hard to calculate proper additions but as you are going to pretty high concentrations it shouldn't matter that the base water concentrations are in error by 10% or so.

The target profile is reasonable in the sense that it physically realizeable (anions and cations do balance reasonably well) which, is not the case with many published profiles. I have no idea as to whether it is representative of the water in West Flanders or not. It certainly has a whopping RA (154) and you'll have to do something to overcome this to set mash pH properly.

WRT the synthesis you do not tell me what pH you want for the synthesized water or what the pH of the starting water was so I must pick values. I assumed the source water was at pH 7 picked the pH for the target water which would allow the closest approximation to the Flanders profile. This is pH 6.61. If you add to 11 gallons of your water the following:

Gypsum: 6 gm
Sodium chloride (kosher i.e. not iodized): 8.4 gm
Epsom Salts: 3.7 gm
Calcium chloride (dihydrate): 0.5 gm
Sodium bicarbonate: 4.7 gm
Chalk: 6.7 gram

the chalk will not dissolve but if you sparge with CO2 until it does and the pH reaches 6.61 then the concentrations of the minerals in the synthesized water will be within a fraction (less than 0.01 mg/L error) of the West Flanders profile. Needless to say this won't actually happen as 1) you couldn't measure the salts accurately enough and 2) the concentrations are based on the reported source water concentrations which we know are in error by more than 0.01 mg/L.

You are probably more interested in a check on the numbers you came up with. If you make the additions you list to 11 gal of your water the chalk won't dissolve unless you use acid. If the acid is carbonic, i.e. if you bubble CO2 (the best fit pH is 6.43 for the additions you propose) then you can get a synthesis with maximum error of -5mg/L in the calcium concentration, 4mg/L in the Mg, Cl and SO4 and 1.5 mg/L in the sodium. Bicarb you can hit spot on but it takes the CO2 to do that. Should you chose to use lactic acid it would take 6.7 ml of the usual 88% solution to get the 11 gal to dissolve the chalk and move the pH to 7. Bicarbonate would be 136 mg/L vs. more than twice that in the target. The other ions would be off by the amounts listed above. So again, the advice would be to skip the chalk and bicarb and go from there unless, of course, you discover that Flanders brewers use lactic acid to treat their water in which case do it that way.

If you really, really want "authentic" Flanders water (and the profile you have is authentic) then this is the approach you should take. The reason you can get such an accurate synthesis is because you are imitating what nature does when west Flanders water is "synthesized" i.e. dissolving calcium carbonate with carbonic acid. If you decide to do it this way you'll spend a day on the water and probably blow through 5 lbs of CO2. My advice would be to skip the chalk and bicarbonate and monitor mash pH. Should it be too low add chalk incrementally to the mash while monitoring until the desired pH is reached. If you can find out more about the brewing process for this beer you may well discover that the water is decarbonated before dough in. This would seem likley as Flanders Red is not that dark a beer and the water profile is quite high in RA. Should it turn out that the brewers of this beer decarbonate their water then the "authentic" route is to do the whole thing with the CO2 and chalk and then decarbonate i.e. take out most of the chalk that you laboriously put in. Why go to all that work? Look at the Flanders profile assuming that it has been decarbonated and try to match that IOW skip the bicarb and carb. Clearly the characteristic of Flanders water that will affect flavor (assuming the carbonate/pH question has been properly addressed) is the remarkably high level of sodium and chloride. The sulfate is pretty appreciable too.

I was at Rodenbach back in March and the head brewer said they use 100% RO water with some lactic acid in the mash. So... I wouldn't go to crazy on this one. If your tap water is truly as soft as you say, then you could simply run it through a carbon filter and acidify the mash liquor with lactic acid.

Wow, that's an intense answer. What I did was adjust the water to half of what I had calculated - I recirced the mash water to keep the chalk in suspension so that it wound up in the mash. The starting water pH was 7.4.

It will be interesting to compare with the batch I brewed with no mineral adjustments.