Need help with water chemistry

[Knightshade]

Yeah..I've probably got about 4 different spreadsheets and they're largely inconsistent. Which doesn't help...I just need to pick one and be done w/it me thinks.

 

[DarrellQ]

Ok, I made some assumptions (e.g. grain wort absorption and boil off rate, 5 gallon batch) which may not match your own, but assuming you're mashing with approx. 7.9 gallon of water, here's what I would probably do.

In Mash: 2.5 grams CaCl2 (just to get a bit of calcium in the mash as an enzyme cofactor and alkalinity offsetter, and some chloride for rounded malty-ness). Mash pH should land in the vicinity of 5.5.

Add After Mash:
1.5 grams CaCl2 (calcium for yeast flocculation, Cl2 for rounded malty-ness)
2 grams CaSO4 (more calcium for yeast flocculation, and a bit of sulfate to balance all the chloride a little)
5.5 grams NaCl (Sodium enhances the chocolate-y flavors)

ETA: the above will result in a profile similar to my big stouts.

New to all grain brewing, so please pardon these basic questions. When do you measure mash pH? After the 60 minutes mashing? Also, how do you determine "the efficiency of the mash?" I assume by measuring OG after the boil? Thanks

 

[VikeMan]

New to all grain brewing, so please pardon these basic questions. When do you measure mash pH? After the 60 minutes mashing?

I measure at about 30 minutes into the mash.

Also, how do you determine "the efficiency of the mash?" I assume by measuring OG after the boil? Thanks

Mash efficiency is a measure of what percentage of total possible sugars and dextrins from the grain bill actually make it into the kettle. You can measure it before the boil or after the boil, because the amount of sugars/dextrins won't change during the boil. Either way, the volume of wort at the time the gravity measurement is taken has to be taken into account, because boiling does change the concentration of sugars/dextrins. I think the most common mistake people make when computing mash efficiency is to measure a post boil gravity and just assume that the post boil volume is what the recipe says it should be, or they know the volume is different, but don't understand why that's important. Further reading:
http://sonsofalchemy.org/wp-content/uploads/2020/04/Mash_Efficiency_and_Brewhouse_Efficiency.pdf

 

[Knightshade]

http://sonsofalchemy.org/wp-content/uploads/2020/04/Mash_Efficiency_and_Brewhouse_Efficiency.pdf

Perhaps it is because I already had a primer of that presentation due to having previously read that section from "How to Brew", but that was really easy to follow. Good info.