I started a batch of cranberry wine following Jack Keller's recipe.
After mixing all the ingredients, the specific gravity was 1.092, the
TA was 0.52%, and the pH was 2.85. I thought that the pH was way too
low, and I was afraid that the yeast wouldn't work, so I added 2 more
cups of water in an attempt to increase it. I added 100 g. of sugar
along with the water in order to maintain the sugar level. It's now
been 36 hours since I pitched the yeast (Pasteur Champagne) and there
is no activity. I increased the room temperature from 70 F to 75 F, and
I've been stirring the must every several hours. What's going on? Is
the low pH killing the yeast? Should I increase the room temperature
some more? Thanks in advance for any suggestions.
what volume of wine are you making? Adding a couple cups of water will
not significantly change pH because pH is a logarithemis scale (so a
wine with a pH of 3 has 10 times the number of protons in solution as a
wine with a pH of 4). You look to be a full pH unit below the optimal
pH range for yeast (3.7-4).
that would be my first guess at your sluggish ferment. Did you pitch
the yeast directly into the wine or did you rehydrate? that low of a
pH could be fairly lethal to a yeast that you pitch directly into the
My first guess is that the low pH is inhibiting yeast activity. I
would add 1/4 tsp of calcium carbonate (or potassium bicarbonate) to
the batch, test the pH (try to get it above 3 at least) and then pitch
Check the similar thread of 2/9/06. Cranberries contain natural Benzoic
acid, which is a preservative & inhibits yeast growth.
Try making a starter and adding your cranberry must to it in small,
increasing increments. Say, a cup of must to a quart of active starter,
then a pint when it's fermenting well again, then a quart, etc. Keep
adding 50% of your fermenting volume, if it will tolerate it. This
method works well for a lot of stuck fermentations, and may work here too.
Mike MTM, Cokesbury, NJ, USA
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This is exactly the problem I had with a recent batch of cranberry wine.
Using Pasteur champagne yeast and following Mike's procedure worked well but
it still took about a week for the fermentation to really take off.
This morning I started another packet of Pasteur Champagne with a
little warm water. Then I mixed it with 1/2 cup of the cranberry must
plus another 1/2 cup of plain water. A couple of hours later it was
fermenting. Then I started adding one cup of must per hour. I have now
transfered about half of all the must and it's still fermenting
vigorously. Anyway, thanks for the suggestions, which saved the day.