Reactivating mead

[Jorge]

I started a batch of mead in september that did not complete fermentation. I want to reactivate it. Would it be OK to add yeast again directly? Should I aireate the most before adding new yeast or should I add it without aireating? Should I rack it first or just add to the most as is?

Thanks, Jorge

[Pilgarlic56]

Hard to say on the information provided. On what basis do you say it failed to complete fermenting? Do you have hydrometer readings? If so, it would be helpful to know 1) Original Gravity, 2) Current Gravity, 3) Recipe, 4) Specific Yeast used, 5) Fermentation regimen, i.e., temperature, stability of temperature or lack thereof, et cet 6) Is it in Primary or Secondary?. If the fermentation has indeed stopped prematurely, it could be for any number of reasons: Lack of nutrients, PH, Temp, Alcohol, et cet. Without knowing whether indeed the fermentation failed to complete and, if it did, why, one can't say how best to revive it.

[Jorge]

Pilgarlic56, thanks for the reply.
You are right, there are lots of variables. So, this is it:
I started with fresh honey (13lbs honey in 5 gal water). Most pasteurized at 145-150oF for ~10 min. The whole thing was let to cool at room temperature. I used Lalvin Bourgovin RC 212 (sold by Dadant), one pack (5 grams) + ½ tsp per gal (= 2.5 tsp) nutrients (Crosby & Baker Ltd.,yeast energizer) activated carefully as recommended on the package.
I kept the fermenter sealed with an air lock at around 70-75 oF pretty constant.
First densitometry reading (Sept 28th): 1.091. Current reading: 1.034. Never saw strong fermentation.
I am not sure what you mean by "6) Is it in Primary or Secondary?" so I can't tell. I have not measured the pH, but I did not add anything to modify that to begin with.

Can you give me any suggestions with this info?

Thanks a lot!!

[Ben Brewcat]

How did they recommend reactivating (I assume the yeast and not the fertilizer)? Did you use energizer or nutrients (they're different)? And did you do anything to aerate/oxygenate at pitching? (DON'T now, either way). Certainly it's lagging a bit at this point, but it'd be interesting to see if there's a SG change over time (still trickling along). It's only at about 7.5%, way below what the yeast can handle if in good health.

Certainly you could repitch some additional yeast, properly rehydrated and oxygenated first (see the stickied thread for dry-yeast tips). For a couple bucks it's cheap insurance.

[Pilgarlic56]

Because of your recipe I wouldn't guess that your fermentation is being held back or stalled by Ph. Temp, too, looks okay. That would leave initial oxygenation or nutrients/energizer. I'm guessing nutrients/energizer. Unfortunately, labeling of additives isn't consistent. You need a source of Free Amino Nitrogen (FAN, often in the form of diammonium phospate (DAP), and also a source of micronutrients (often including spent yeast hulls). I looked at the Crosby and Baker product and couldn't tell what it contains, although it mentioned "nutrients". It may pay to add DAP at this point, and/or micronutrients.

[Jorge]

OK. Thanks for the advice, guys!