The window is now open to ask Gordon Strong questions! Good evening Gordon,
Is there a preference with brewers that you know, in regard to adjusting brewing water ph vs monitoring mash ph and directly adjusting the mash. Thanks for your time.
Snook, the Q&A period is officially closed now. But maybe Gordon will pop in and see you question.
Although, I can tell you he'll say mash pH is the key.
Mash pH is the key, but I personally adjust my brewing water to get that. I use RO water, which makes the whole process really repeatable. I think it's better to get your brewing process set up so that you never have to adjust your mash pH. So, just to be clear, I normally hit my RO water with about 1/4 tsp of 10% phosphoric acid per 5 gallons of RO water, which gives me a pH of around 5.5. I measured that in a lab several times, so I know it's repeatable on my system. So now I just measure the volume of strike water and the volume of phosphoric and I know I hit my target. Using that kind of mash water with a pale grain mash settles in the desirable range every time.
But I know this because I measured it several times until I knew that's how it worked on my system with my ingredients. Verify that it works that way for you and you can do something similar.
So the mash pH is what is ultimately what you want to control, but you tend to do it indirectly by adjusting the strike water pH and using an appropriate grist for that type of water. You can do it other ways, but it tends to involve spreadsheets and gram scales, and is different for every batch. My method is repeatable, so I don't worry about those things any more.
I tend to use about 1 tsp of CaCl2 in the mash to give me some available calcium. That salt doesn't affect the pH like gypsum or chalk does. If I want to add those flavor ions, I'll tend to do so after the mash is done. Likewise, I'll add the various dark grains and crystal malts after the mash. Those grains don't need to be mashed, so you don't need to add them early. During the vorlauf is fine. That has other beneficial effects in my experience, but not worrying about mash pH ever is something that I think is a great simplification to my process.
I've brewed about 20 batches this fall, from extremely pale to extremely dark, all basically using the same water, and all tasting great. Anyone who tells you that you must vary your water chemistry significantly to brew those is making too many assumptions about your brewing process; there are other ways that work just fine.
But don't interpret this advice to mean that "Gordon said that you can ignore water chemistry entirely and brew whatever you want" -- pay attention to the control points that I said were important. My approach assumes a specific method; if you do something else you might get different results. Just remember that as long as your mash pH is in a good range and your beer tastes good when you're done, don't worry about it. I don't.