Apologies PoN, it wasn't a crack at you but at a general approach to brewing on this forum and others where people rely on a spreadsheet to come up with what is a very important aspect of brewing. Very few people measure it. 4/5ths of FA understand it. There are plenty of very good books on this topic, the late Dr George Fix's 'Principles of Brewing Science' is a good introduction. Once you've got a clear understanding, Brewing: Science and Practice is the next step but that can be quite chewy. One take home message for me is - search BS&P for the term 'alkalinity'. In over 800 pages the word appears twice. Not one mention of the term 'residual alkalinity'. The conclusion i draw from this is that residual alkalinity is a made up term in the homebrewing community.
Water chemistry is indeed a very complicated area, I've been a chemistry researcher for >20 years and am still constantly learning. In my opinion, the spreadsheets circulating that calculate water chemistry values do not take in to account the buffering capacity of the mash itself nor do many people including those who call themselves scientists, understand the basic concept of an equilibrium. What happens is an engineer comes up with a way of calculating something without the fundamental understanding of the underlying chemistry.
Rant over, **** i need a coffee and possibly a pint of RIS.
