[SCOTTinLHC]

The 8gals of (combo) mead have been bubbling along, but today I only notice a very slight bubble. Thinking of a stuck fermentation, I tested the PH.

My test strips only go from 3-6, and the color was almost the same as the original paper. So we're looking at a very low PH, which if (faulty) memory serves, means it's acidic. But... it's ONLY Honey, water & yeast.

I did the test 3 times (must is at 61F), and they all came out the same.

Suggestions? Time to add Calcium Carbonate? Other ideas?

Thanks all!

[psolio]

First off, pH strips are not reliable IMHO.

You are right that a low pH is a high acidity. However, saying it is only honey, water, and yeast doesn't mean it can't be acidic. Do you know the pH of the original honey and water, separately and then combined? Also, you indicate that there has been fermentation - which changes a lot about the solution - yeast can change the whole dynamic. For one example, the CO2 production of the yeast allows it to become dissolved in solution creating carbonic acid.

Have you trying giving it a good shake to stir the yeast back into suspension and help drive off some of that CO2 out of solution?

[SCOTTinLHC]

The original PH was 5.8 according to the strips. So this means I've had over a 6-point drop due to fermentation or aliens.

Guess it's time for Calcium Whatever-I-can-find. Pity it wasn't the other direction - I have a ton of Citric Acid.

[psolio]

Most wines have a pH of 2.8 to 4.0, so don't get carried away trying to make it too alkaline. For fermentation though, try to get the pH up to 3.5 range.

The original must was 5.8? Water is generally 5.0 to 8.0 and honey is around 3.9 or so. Conceivably your pH reading was close at the beginning. Yeast prefer an acidic environment of around 3.5 to 4.5

[psolio]

SCOTTinLHC, on 19 November 2009 - 07:34 PM, said:

Guess it's time for Calcium Whatever-I-can-find.

Try to find Potassium carbonate - that would be best. Calcium carbonate will work, but it takes longer to precipitate and negatively affects flavour. Potassium carbonate will require cold stabilization though.

[strangebrewer]

before you do anything mix it up and test again. particularly with mead musts I have had wildly different results when testing the pH of the must at the surface of the bucket vs a sample after mixing it up. I too have tested a mead must with my pH meter which is accurate to .02 +/- . My starting pH was in the mid 5's and 24 hours later after fermentation started and I mixed it to degass and take a 2nd samle I was in the mid 3's. I have a hard time believing it dropped 2 points in 24 hours.

I agree the standard pH test strips are not the most reliable but if it's all you got then it's all you got. Use them as a tool to give you an idea but I wouldn't base my decisions to adjust a must pH based on their results alone.

[fatbloke]

This is one of the reasons why some people say that with meads, you shouldn't really add acids until after the ferment has finished.

pH tests are a blunt instrument, inasfaras they only test the flat level of acidity. whereas, during the ferment of meads, the honey generates gluconic acid, which is why you'd show some quite wide swings in acidity/pH level.

This does dissipate though, hence if the must is somewhere between 3.5 and about 5.5 pH prior to pitch, then you could probably just run with it and then add acid (my own favourite is a mix of 2/3 malic to 1/3 tartaric) to taste.

There are a number of routes that people follow with stuff like this, yes, I do personally normally make sure my must is somewhere between 3.5 and 4.5 pH but I do have to keep an eye on it. I'd start with getting a cheap pocket sized pH meter (they're not expensive) to check it and then if it's below 3, I'd hit it with potassium carbonate to bring it up some...