Blending wizard with PH calculation

[Tom Lopez]

I was using Claude's blending wizard this week and wondered about the lack of PH calculations. I did a little research and believe I was able to get this working. There's an extra calculation needed, PH conversion to "Hydrogen ion concentration" which can be averaged by volume and then converted back to PH.

I'd be interested to hear if anyone thinks I've gotten this wrong, it's pretty closely matched up to PH tests on 5 blends so far.

I thought this might be of some use to someone, so please find an example sheet attached. 

[Claude Jolicoeur]

Looks good to me.

It might not account for some buffer effects, but probably could give a fairly good first approximation of the pH of the blend.

Only testing against real life data may tell how good it is...

[CGJ]

I played around with the same basic concept of transforming to H+
concentration for mixing calculations about 15 years ago when I was
planning my orchard, long before I had ever even attempted a rudimentary
fermentation. Wiser or more experienced heads might know some reason
this won't work, but it sure seems that it should give a good first
approximation.

It would be great to see the data on your 5 test blends, if you'd care
to share.

Carl Johnson
West Barnstable
Massachusetts

[Jonathan Miner]

This is very handy. Thanks for sharing, Tom. 

I have about 200 lbs of Dabinettes and equal volume of mixed/unknown crab and desert apples that I will be pressing this weekend. 

I plan to do some blending experiments on the juice, and hopefully try Keeving about 20 liters of this year's cider run with a PME kit that Claude posted about in a separate thread. 

I'll utilize your calculator and run some independent PH measures on the mixes. Will report back if I see any deviations from the data and the spreadsheet. 

Best,

Jonathan

[Tom Lopez]

Sorry, I missed the earlier request for my test blend data.

They were all just different blends of the two juices I had available (Dabinett the bittersweet and Browns the sharp) and the spreadsheet matched my electronic PH meter from the real blend I was aiming at just under 3.7ph at 5:2 all the way through to the opposite ratio 2:5 at 3.3ph

Unfortunately my PH meter gave up before my next round of pressing, and I was left with only strips.
The calculator still functioned with the data from the strips to get me quickly into the safe zone under 3.8, though I've no idea how accurately. 

Hopefully next year I'll get a better testing setup and provide some better data.