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scbeec
02-20-2007, 09:37 PM
I have a batch whose pH has dropped below 3.5 in the first few days. It's perking along nicely in my opinion (2 bubbles per second during the first week). Do I need to raise the pH above 3.5 or should I leave well enough alone? I don't want to control something that is taking care of itself or fix something that isn't broken.

I'm trying to follow the general meadmaking rules, but maybe it's like beekeeping, where sometimes, the bees just know what they're doing and you have to let them be.

Is this where I follow Papazian's Golden Rule??

Dan McFeeley
02-21-2007, 02:07 AM
I'd say leave it alone. The pH of the must doesn't start to inhibit the fermentation until about 3.2 or 3.2, so it looks like everything is fine here.

Have you also been checking the gravity? Where is it at about now? This will also give you an idea of the progression of the fermentation.

scbeec
02-21-2007, 09:32 AM
I have a few batches behaving like this - here are my stats:

Batch 1
Date pH SG
Jan 27 5.24 1.090
Jan 28 4.45 1.089
Jan 29 3.39 1.083
Jan 30 3.17 1.072
Feb 2 3.06
Feb 11 3.20 1.022
Feb 18 3.27 1.010

Batch 2
Date pH SG
Feb 17 5.60 1.083
Feb 19 3.61 1.072

So, obviously, things are happening since the gravity's changing...that's why I didn't want to just go ahead and mess with it.

My 1 gal. test batch is dropping like that too. The fermentation slowed in it, but the gravity's way down. Here's what happened there:

Date pH SG
Feb 4 4.59 1.110
Feb 6 3.36 1.090
Feb 7 3.28 1.078
Feb 18 3.35 1.014

So, while there's little airlock activity, it's almost dropped by 0.100 - I'm guessing that means it's ok?

I guess I'm a bit nervous because the low pH issue is always one of the first troubleshooting answers for slowed fermentation - just can't figure out why mine isn't slowing. Why is my mead defying the laws of physics and chemistry (and biology and biochemistry)? And if it's going to do that, how the heck can I apply the rules to it?

Dan McFeeley
02-21-2007, 04:30 PM
Rules? There are rules in meadmaking? ;D

Thanks for posting the stats -- gives a better picture of what's been happening with the fermentation.

The yeast strain you're using may be part of this. Some may be able to handle the lower pH better than other strains.

scbeec
02-22-2007, 12:20 AM
Aaahhh, the yeast variable. Of course. Well, thanks for your input - maybe I should just relax a bit. Wouldn't want to taint my mead with worry vibes. I really appreciate your taking the time. :icon_salut:

Oskaar
02-22-2007, 04:42 AM
There are certain yeast strains I use that will ferment very vigorously at pH as low as 3.1 (DV10 springs to mind) so it's a function of how much experience you have with a certain yeast, and what levels you've found that those certain yeasts will tolerate before giving up the ghost.

Cheers,

Oskaar

scbeec
02-22-2007, 10:36 AM
I checked the Lalvin site, and while I didn't find data on pH tolerance of the yeasts, there's a nice pile of detailed info on each of the ones they offer. For anyone who wants to get to know their Lalvin yeast better check out www.lalvinyeast.com/strains.asp (http://www.lalvinyeast.com/strains.asp)

Medsen Fey
11-05-2007, 10:46 AM
Does anyone know where one can look to locate the ph tolerances of the various yeast strains?

Thanks,
Medsen