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hedgehog
08-06-2005, 02:19 PM
Ok.. I am going to ramble a bit about my latest mead batches. In the "momentarily more than 1 gallon" post in the brewlog, I mention how I made a 3 gallon light honey must and then divided it into 3 x 1 gallon batches after 20 days of primary. One of the batches, I racked onto sassifras tea, which had potassium sorbate in it. Since the SG had dropped pretty low 1.030, I was expecting the yeasts to go for a day or so then slowly fizzle away from the K sorbate and low sugar levels. Almost a week later, the batch is going like gangbusters. Its actually out "glugging" both the jasmine flower and the red tea meads, which both had more honey added. Now the sassifras tea mead has a tendency for all the dark stuff to drop out(almost clear otherwise, but shaking redissolves it), but is fermenting very rapidly. I emailed the company that makes the tea to find out how much K sorbate is in there. They told me that their product contains 0.15% K sorbate as a preservative. Their product is 12 fluid ounces, so my math tells me there is about 0.018oz of K sorbate in a bottle. Hoping my math works, that says 0.018oz in a 128 oz gallon puts the K sorbate at 140.625ppm. If this were bleach or sulfate, the yeasts should be toast. I am not an expert on yeast, nor on sorbate, but shouldn't this level of sorbate slow the yeast down instead of urging them on?? The yeast are taking off like I put some mega-yeast vitamin in there, instead of a few roadblocks.
I will admit that the company said that many homebrewers use their product for wines with no problem from the sorbate. Some of the other things mentioned in the email lead me to believe that the others are using one bottle in bigger (5/6/12.5 gallon) batches. One bottle in 5 gallons puts the sorbate at 28.125ppm, which should be much less trouble for yeasts. Though they did say that if i wanted, I could buy a 5 gallon bucket of sorbate free sassifras tea. Though they said I would have to use it within a couple of weeks.
so what do you all think?? Am I expecting too much out of my sorbate? Or should I just shut up and enjoy the sound of happily glugging carboys?
hedgehog

David Baldwin
08-06-2005, 02:41 PM
Hedgehog,

I'm not quite the micro-bio guru that some others are here, but here's my $.02 worth.

Sorbate alone will not stop a healthy active fermentation (confirmed that on my first batch of pyment) It should however prevent dormant yeast from becoming active again. It sounds to me like you have a super healthy ferment going, and that the yeast found something in that sassafras tea to encourage them along in their mad sugar-feeding frenzy.



David

Oskaar
08-06-2005, 02:49 PM
Hey HH,

I agree with David. K-sorbate will not prevent or otherwise stop an active fermentation.

Your current gravity also plays a role because if it works out to give you an ABV of 10% or less you'll need 200 ppm (about .75 grams/gallon) for the K-sorbate to prevent re-fermentation once your current fermentation has stopped.

Based on your OG, and the fact that you diluted the batch when you racked, I'd guess that your PABV is below 10%, that may or not be the case, but it bears investigation.

Also if your pH is around 3.5 or exceeds that you'll need more sorbate.

Hope that helps,

Oskaar

hedgehog
08-06-2005, 10:21 PM
thanks Oskaar and David,
somehow, since the 3 gallon was slowly glugging(1 glug every 2 mins), i figured the yeast were seriously quieting down and the sorbate would make them taper off more quickly. Especially at a low SG of 1.030. I seriously forgot about the low ABV part. Not sure about the pH, though I won't check unless I do something more to the mead.
To be honest, since the yeasts have kicked back up nicely, i am tempted to wine thief a few samples to lower the volume a tad and add some more honey to bring the ABV up a bit more.
While it would be messing with what I orignally planned, I think it would end up a much nicer mead. What do you all think??
And as well, I am curious to see if the "non-lethal" dose of sorbate is going to stress the yeast into doing off-tastes. The samples might tell..
anyhow, thanks again guys,
hedgehog

Miriam
08-08-2005, 01:22 AM
While it would be messing with what I orignally planned, I think it would end up a much nicer mead. What do you all think??

That's what it's all about, Hedgehog - brewing a mead you like to drink! It's neat when a wine comes out just about how you planned it, but I don't take it for granted that it will. Even with a standard, well-known recipe, unique factors coming from my unique circumstances alter the must and its progress to finished mead. Every brewlog is different, sometimes slightly and sometimes greatly. I think that's part of the fun: following this dynamic process and intervening to change the product to my taste as it goes on.

Miriam