Salt Additions

I know that this topic has a lot of information posted on it but there is one question out there that I cant really find an answer for. When shooting for a certain concentration in a water profile is it with the total water used or the final volume of beer?  For example, if I was looking to have 50ppm calcium for yeast health and I add the proper amount of calcium chloride in ten gallons of water won’t I end up with a higher concentration in the end since now I have boiled off 5 gallons of water to achieve 5 gallons of wort?

AFAIK the concentrations always refer to the water.  There are so many other factors affecting what’s in the finished beer.  Concentration by boiling, yes.  But also mineral contributions from malt, consumption and precipitation of minerals during mashing, boiling, and fermentation,  and so on.  If someone says water should have so much of a mineral for some purpose, assume it just means the water.

According to Martin Brungard, 25 ppm of CA is all that’s really needed.  AFAIK, Ca doesn’t necessarily promote yeast health, it promotes flocculation.  The amounts are for the volume of water you use.  Martin, if I’m putting words in your mouth, please correct me!

So if my sparge water ph is low enough I could just treat my mash as if 10 gallons of water is going to go through it?

As long as the boil off evaporation isn’t excessive, planning your salt additions on the total water volume used is appropriate. If your practice is to boil off a lot of volume, then you may need to dial back the additions based on the final volume.

As Denny pointed out, brewing water doesn’t HAVE to contain a lot of calcium. That’s because malt delivers all the calcium that yeast need for their metabolism. I haven’t recommended a minimum of 25 ppm, since there isn’t a real need. But I have recommended a 40 ppm minimum in the mashing water. I often add all my batch’s calcium to the mashing water to get it to 40 ppm and then I let the straight RO sparging water dilute that down in the final wort.

I would say that in most 5 gallon batches about 4 gallons of sparge water is used, so if I’m treating 9 gallons of water and then boiling down to 5 gallons aren’t my concentrations going to be higher. Maybe calcium was a bad example. What about ones that effect flavor like chlorides and sulfates? Doesn’t the taste of beer come from the final product concentrations?