atomicpunk wrote:Thanks for the replies guys. AJ, do you use one of the many water spreadsheets to arrive at those pH levels you stated? If so which one? I trust you numbers, would just like to crunch the numbers as well.
I have a spreadsheet I developed for my own use. It uses Kolbachs observation that each ppm of residual alkalinity translates to a pH shift of +0.00168 (negative RA lowers pH by the same amount) and RA is calculated simply as alkalinity - (calcium_hardness + magnesium_hardness/2)/3.5. These are both simple to program into a spreadsheet. I don't generally mention my spreadsheet because it has grown to a level of complexity that makes it intimidating to most. If you want it, it is available at
www.wetnewf.org.
The rest of the pH shift is a rule of thumb posted by Weyermann on their website. That is the 0.1pH reduction for each percent sauermalz in the grist.
atomicpunk wrote:And speaking of pH. I noticed on my lab report that the pH of my water was not stated. Is that something I need to know or does it not matter, or were you able to calc it from the various numbers in my report.
I can, conceptually, compute the pH of your water from the other numbers by noting that in a real water sample the charges on the cations must equal the charges on the anions and finding the pH that satisfies that condition. In the case of the numbers you gave that pH is 5.53 but I doubt very much that that is your water's pH. Small errors in the reported calculations, i.e. errors of the magnitude typical of measurement error, can throw the pH calculation way off.
Fortunately, the pH of the water doesn't make much difference unless it is above 9. The alkalinity is a measure of buffering capacity and it is buffering capacity that really determines where mash pH is likely to come in and that's where its power lies. My spreadsheet does need to know the water's pH in order to do it's ion distribution calculations. I just put in 7 when looking at a report in which a value is not furnished.
atomicpunk wrote:Does that sauermalz need to be crushed? Almost sounds like the acid is on the outside of the grain.
There are 2 ways to make the stuff. One is to prepare an unhopped wort, innoculate it with lactobacillus and let them ferment the sugar to lactic acid. This is called sauergut and it is sometimes used directly and sometimes sprayed onto malt which is then dried. The other way is to moisten malt, hold it at 47 °C and let the L. delbrueckii naturally found on the surface to ferment some of the sugars. When the pH of this mash stops dropping the malt is dried. So in either case the action is at the surface but some of the acid has soaked into the kernel in either case so you do want to crush it. Besides, it lends other flavors and even some extract.
