Unhappy yeast? Slow...

[jh0330]

Hi, I am currently making my first batch of blackberry wine.
Its been 35 days since I first pitched yeast and after 2 rackings (from primary to secondary, and then off the gross lees) the wine is now sitting in 2 single-gallon jugs but still not done fermenting.
I had an initial SG1.116.
Currently I have SG1.006 and SG1.010. The SG is dropping very very slowly and there are very little CO2 bubbles.
I have only added 2 campden tablets to my 2.5, or now 2 gallon wine pre-fermentation.
I am using K1 V1116 yeast but I have never added any energizers or nutrients.

Does my yeast need any nutrients, oxygen, or energizers?

 

[sour_grapes]

It is surprising that K1 V1116 has not (yet) been able to take that all the way to dry. You have a healthy amount of alcohol, but that strain should be able to take it.

You raise a good question about nutrients at this stage of the game. Scottlabs has a protocol for restarting stuck fermentations (http://www.scottlab.com/uploads/documents/downloads/136/2010RestartStuck.pdf). In general, this procedure calls for making a yeast starter and adding nutrients; however, for your level of remaining sugar, it says to use only half as much nutrients, and for a bit lower sugar, it says not to use any nutrients at all.

If it were my wine, I would be tempted to try making a starter, using either V1116 again or EC1118 (one of the other strong fermenters), with a little bit of nutrient.

 

[Floandgary]

If you've racked it twice so far, you may well have taken away what the yeast needs,,, food! Also how about temperature? 75F-80F sure helps move things along. As Paul said, a starter of appropriate proportions may help as well. G'Luck

 

[jh0330]

If you've racked it twice so far, you may well have taken away what the yeast needs,,, food! Also how about temperature? 75F-80F sure helps move things along. As Paul said, a starter of appropriate proportions may help as well. G'Luck

I always try to keep the temperature under 85F (I read that K1 is okay until 90F) but I was away for two weeks but still I would think that it would still be under 90F. Right now it is always under 80F.

It is surprising that K1 V1116 has not (yet) been able to take that all the way to dry. You have a healthy amount of alcohol, but that strain should be able to take it.

You raise a good question about nutrients at this stage of the game. Scottlabs has a protocol for restarting stuck fermentations (http://www.scottlab.com/uploads/documents/downloads/136/2010RestartStuck.pdf). In general, this procedure calls for making a yeast starter and adding nutrients; however, for your level of remaining sugar, it says to use only half as much nutrients, and for a bit lower sugar, it says not to use any nutrients at all.

If it were my wine, I would be tempted to try making a starter, using either V1116 again or EC1118 (one of the other strong fermenters), with a little bit of nutrient.

Thanks for the link!
I was initially thinking of just adding nutrients directly into my jugs.
Perhaps this is a better way of doing things.
I am planing on doing this but method it seems like a lot of extra work without fully understanding why you should do portions. If my local homebrew shop is open ill try getting some yeast and nutrients.

 

[jh0330]

Yep its as I suspected.
Stuck fermentation.
My SG is still 1.010 and 1.004 or 1.006

If I am going to back sweeten, should I just not bother with starting the yeast back up again?
The taste definitely needs improving. I was hoping time will do this. Perhaps completely drying the must will male it taste better?

Here is a pretty neat part though.
I actually had well over 2 gallons at first but each single gallon jug had well over 2 inche of white powdery lees. I was just barely able to rack them into 2 full s 1gallon jugs and then collected the lees into a separate gallon jar with lots of headspace. I kept this jug out for about 10 days then decided to refrigerate. A few days after, the jug had a bit under half lees and half crystal clear wine. I decided to be couragous and taste test. I did not care much about this jug but to my surprise, the wine tasted absolutely dry. I read 0.990SG.
The wine tasted bitter and dry (stirring sugar improved taste test) with a hint of oak. I racked it off the lees and into a 750mL Glenlivet bottle and used its cork lid. Colour is deep red. Taste still definitely still needs improving.

My 2 full single gallon jugs with stuck fermentation are really dark in colour like black and really clear. They both taste a bit sweet with the ending flavour being overpowered by oak flavour.
Or I think it is oak...?

 

[jh0330]

Questions,
1.010SG and 1.004SG is acceptable in terms of sweetness.
However, there is a powerful after taste. -which I believe is the oak (although it doesn't taste like the smokey oak in glenlivet whiskey).
I am hoping the aftertaste mellows out a bit with time before bottling - in a month or two.

1) Is this oak taste or because the yeast was unhapppy?
2) If this sweetness is okay for me, do I have to re-start fermentation? (I was thinking of mixing the two for 1.007SG before bottling once the taste improves)