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RA over SRM simulation

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Tonight I finally finished something quite interesting that I was working on for the last few days. I'm trying to come up with RA guidelines based on the beer SRM. Similar to what John Palmer is already doing but based on my research with respect to malt acidity and water chemistry.

I ended up writing a script that can create random recipes based on a few guidelines. There are different types of recipe templates as well. Those templates are for example "all base malts" "base malts and up to 15% cystal malts", "base malts and up to 15% roasted malts" .... and a few more that I don't feel like listing. For these recipes I can use the pH estimator that I'm working on and which seems to work for my few recent beers. That allows me to determine the SRM of the beer and the necessary residual alkalinty to reach a pH of 5.2, 5.4 and 5.6. For the ~140 "recipes" I plotted that RA over the beer SRM and also included John Palmer's min and max RA guideline and this is what I came up with:

I expected some spread, but not that much. No wonder than breweries like Stone can use their 100 ppm CaCO3 hardness water for such a wide range of styles. And there are also a number of outliers. Beers that would need a ridiculously high or low RA to create an acceptable mash pH.

I have yet to do more qualification on that data and possibly limit the recipe templates some more to create even more realistic recipes. Stay tuned for that. Right now I just felt like sharing that chart.


RA are two letters that mean nothing to me off the top of my head,  Kai could you provide a description of that please.

Also each of your pH ranges seems to correlate with the Palmer lines.  I'd suggest a best fit line for each range to make the chart a bit more clear


RA measns residual alkalinity. Sorry I implied that.


So the data is showing that for most beers you will need an RA of < 0 to achieve a pH of 5.2 regardless of color?


--- Quote from: ndcube on December 03, 2009, 07:09:04 AM ---So the data is showing that for most beers you will need an RA of < 0 to achieve a pH of 5.2 regardless of color?

--- End quote ---

I have read his post three or four time and I have been wondering what the actual conclusion was. Damn, I am no scientist, that is for sure. The only conclusion I came to was that there is a wider water mineral profile applicable to individual styles than is often thought (?)

Kai, can you dumb it down for the rest of us "non-German engineering types" please?  :-\  ;)


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