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gregoryc
08-05-2010, 08:49 PM
I just finished mixing up my first batch of mead, a traditional using cranberry honey.
My recipe:
12# cranberry honey
4 gallons spring water
5gm Fermaid K
8gm Lalvin DV10 rehydrated in Go-Ferm Protect

My starting gravity was about 1.085 and the pH of the mixed must was well over 4.4 using pH range 2.8-4.4 dipsticks. I tested the strips thinking maybe they'd been in the LHBS too long and they indicated vinegar at 3.2 and lemon juice at 2.8 and >4.4 with tap water.

I've read that the starting pH needs to be in the 3.7 range or lower to prevent spoilage and I'm not sure what to do now. Having the must all mixed up I went ahead and pitched the yeast. Do I need to add acid mix now or should I just wait and see?

Medsen Fey
08-05-2010, 09:09 PM
You don't need to worry about high pH prior to fermentation. After fermentation is over, it is best if the pH is <4.0 to discourage spoilage organisms. At this time you don't need to add anything.

Once the fermentation starts, the organic acids produced by the yeast and the CO2 forming carbonic acid will drop the pH down within the first 24-48 hours in most cases. In traditional meads, it is frequent that the drop is considerable, sometimes low enough to inhibit the yeast, but DV10 is pretty tolerant so I doubt you'll have much to worry about. Still I would check the pH again at 24 hours and 48 hours.

And Welcome to GotMead!

Medsen

gregoryc
08-06-2010, 12:21 PM
Thank you very much Medsen.

Dan McFeeley
08-06-2010, 02:18 PM
The 3.7 pH figure originated in an article on meadmaking written in the mid 1960s by Roger Morse and Keith Steinkrauss of the University or Cornell. They felt a pH of 3.7 was the best compromise between a pH high enough to encourage yeast fermentation, but still low enough to inhibit bacterial growth.

It's a good figure to work with, but not necessarily absolute. Yeast strains available today have varying responses to different pH levels -- our yeast gurus on these forums can probably add more info on this.

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fatbloke
08-07-2010, 03:25 AM
Perhaps we should have a "definitions"/glossary page here, and suggest to the new(er) members to read and use it like a dictionary......

"high" pH to me, means higher than neutral i.e. above 7

whereas "low" pH would be more acidic i.e. lower than 7

unless the author needs to indicate higher acid then it might be suggested to use the phrase "higher acid/acidity" and vice versa for more alkaline....

This isn't to be picky, but just to be able to clarify exactly what the poster/author means and prevent ambiguity........

regards

fatbloke

Dan McFeeley
08-07-2010, 10:14 AM
We've got a glossary section, it's listed in the yellow sidebar to the left. I took a look at the entry for pH, it does look like it could be expanded on.

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AToE
08-07-2010, 01:43 PM
Seems like any "high" and "low" PH definitions on this site should be geared towards fermenting though. Obviously anything under 5 is low, but not for our purposes.

Safest would be to include both maybe, it would just stink for some newb to read it and think that they had to keep the PH over 5 or something goofy.

akueck
08-07-2010, 03:57 PM
I can't edit the glossary items that site admin post (lest I tear the fabric of space and time), but I have added another entry which hopefully is more helpful. Need more glossary? PM me!

epetkus
08-07-2010, 10:32 PM
I echo Medsens comments. Nearly all of my traditional start at over 4.4, and then soon after the lag phase are back in the readable range of the dip sticks.

Mead on!

Eric

wildoates
08-09-2010, 05:30 AM
My son got me a pH meter for Christmas, but I haven't used it yet...I don't even know HOW to use it, actually. Guess I better figure it out before I start my next batch. :)

gregoryc
08-09-2010, 10:56 AM
Re: high/low pH, for clarification I was using the term in a relative sense, i.e. high with respect to what one might want. In this sense the pH may be "high" and yet still be on the acidic side of neutral.

gregoryc
08-09-2010, 11:06 AM
As a progress report at 24,48,& 68 hrs, the pH was 4.0, 4.0, and just a hair below 4.0 respectively with SG's 1.078, 1.068, & 1.062. Gravities are not dropping quiite as briskly as I might have expected for the yeast used but getting the job done. Thanks for all the responses.

Greg

P.S. How far apart can I space future SG readings? I'm reluctant to open the fermenter oftener than necessary for fear of contamination.