Very low alkalinity - Brewing Porter

This will be the first time I'm adding anything to my water for my all grain brews...

I'm doing a Vanilla Maple Porter and using John Palmer's spreadsheet, came out with needing to add 17 grams of baking soda to get the alkalinity I need for my SRM which is 42.

I wanted to post to see if anyone can tell me if this is correct or not. I read another thread on another site where someone in my area was suggested to add 90/10 or 80/20 gypsum to baking soda for his Porter but under Additional Hardness Needed there's a big fat 0, which adding any gypsum would bump up.

Here are the numbers for my local water...

Target Color (SRM) 42
Est. RA (Low) 390
Est. RA (High) 449

Calcium 23.6ppm
Magnesium 5ppm
Alkalinity as CaCO3 50
Sodium N/A (doesn't change anything if I put numbers in here anyways)
Chloride 29ppm
Sulfate 30ppm
Water pH 7.2

Effective Hardness 20
Residual Alkalinity 31
SRM Range 8-13

Target R/A 420
Mash water 7 gal
Additional Hardness Needed 0
Additional Alkalinity Needed 389
Target RA SRM 40-44

17 grams of Baking Soda/NaHCO3 would give me 382 additional alkalinity.

Is it just that easy to add a few teaspoons of Baking soda to my mash water to get me where I need to be?

Thanks for any help!

You certainly do not need an RA of 400 to brew a porter nor do you need 17 grams of baking soda. One brewed with such an RA would probably be awful. What you do need is enough alkalinity to keep the pH from dropping too low and that very well may be none beyond what is in the water unless you go overboard with the dark malts. As they can be quite variable both in their titratable acidities and in the amounts used in different recipes it is almost essential that you obtain and use a pH meter to check the mash pH when these beers are made. However if you are keeping roast grains to 20% or less of the grist and are not using any or little dark crystal malts it is likely you will be just fine with this porter. Have you brewed it before with untreated water? If so, how did it turn out? If it was good and you add all that alkalinity you will be fixing something that isn't broken. If it wasn't that good then the first thing you need to check is the mash pH. It could be either too high or too low. A pH meter reading is the only way to tell.

Once you get the pH under control - and that's critical - you can start fiddling with additions of chloride (smooth, soften, round, sweeten the beer) and sulfate (render the hops more pronounced, harsher, drier) to tweak flavor to your tastes. Your pH may be fine without treatment (in fact it probably is) but you need to verify that.

Alkalinity is usually to be avoided in brewing. Therefore you should never add alkali to mash or water unless a valid pH meter reading of the mash has shown it to be necessary.

You can also steep your dark malts separately. This will keep the PH for your main mash in check, and steeping the dark grains will still give you flavor/color.

I just brewed (Sunday) an estimated 47 SRM American Stout with water that had negative residual alkalinity.

The mash pH, measured with a freshly calibrated meter: 5.37.

Typical data point. When I do Irish stout with water similar to OP's (I'm in McLean) mash pH is always pretty close to 5.5. Only dark grain is 10% roast barley. Color usually come out about 70 SRM.

Never used a pH meter, but perhaps I will invest in one. Never treated my water pre brew either.

I don't think I'm using any roasted barley, but some chocolate, crystal, and a small amount of black malt.

reidjoshua said:

Never used a pH meter, but perhaps I will invest in one. Never treated my water pre brew either.

I don't think I'm using any roasted barley, but some chocolate, crystal, and a small amount of black malt.

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Then you definitely don't need to add alkalinity!

For the most part, a brewer rarely needs to add anything to INcrease the pH- usually, the pH is too high.

Ignore any advice to add alkalinity to darker beers until you've brewed it and found that the mash pH was indeed too low.

ajdelange said:

Typical data point. When I do Irish stout with water similar to OP's (I'm in McLean) mash pH is always pretty close to 5.5. Only dark grain is 10% roast barley. Color usually come out about 70 SRM.

Click to expand...

Do you treat your water when doing dark beers?

Yooper said:

Then you definitely don't need to add alkalinity!

For the most part, a brewer rarely needs to add anything to INcrease the pH- usually, the pH is too high.

Ignore any advice to add alkalinity to darker beers until you've brewed it and found that the mash pH was indeed too low.

Click to expand...

Ok, I'm going to invest in a pH meter immediately.

reidjoshua said:

Do you treat your water when doing dark beers?

Click to expand...

For stout, no. For Märzen/O'fest (which isn't really all that dark) I use RO water to which some calcium chloride has been added.

Ok, the avg results from Jan to July for this year is pH 7.9 SU. seems kind of high.

Not sure what you are referring to here but I'll assume it's the pH of the water the Corps puts out of the Delacarlia plant. It is not high (anything below 8.3 is considered acceptable and many municipalities put out water with pH higher than that) nor is it of concern as the pH by itself is not very telling to a brewer. What is important is the alkalinity which is modest at 50.