frustrated with stuck fermentations

[olusteebus]

I have had several stuck fermentations. Most of them not being a kit but I have had kits stop at 1.000 or so.

What I have now is a blackberry jam wine that has stopped at 1.030. I know blackberry can be difficult.

before I pitched the yeast, I added go firm 24 hours in advance.I then rehydrated the 1118 and after it started to ferment, I added fermaid K. After it had fermented about 1/3, I added fermaid K again. I stirred every day and the temp is kept at 23.3 celsius all the time.

I don't know if this would have anything to contribute to the stuck ferment but I do believe I put in too much fermaid K both times. I did not have a scale.

I have just put in some energizer but it is not doing anything at all. I am waiting but I don't feel real good about this because I have had such problems restarting a ferment. At least I have a good bit of sugar left now.

If it does not start, I will take out a gallon and go through the process of repitching some 1118.

I make wine in my cellar which is without a floor, It gets very moist in the summer. Right now the temp is probably 60 degrees or so. Could I be getting wild yeast challenging my ferment?

 

[olusteebus]

I added energizer about 3 hours ago. I am seeing some activity but it is ever so small. Seems to be bubbling a little. It would be great if it took off again.

 

[cpfan]

starting sg? was it high?

Which kits only dropped to 1.000? Did you make any tweaks? When the Cellar Classic Winery Series kits first came out they rarely dropped below 1.000 (not sure what they are doing recently).

Have you checked your hydrometer's calibration?

Steve

 

[Julie]

I would warm your must up some, 60 degrees is pretty low and if you have it on a bare floor, that maybe sucking what heat it has out. And no wild yeast would not challenge your 1118

 

[Bergmann]

I would warm your must up some, 60 degrees is pretty low and if you have it on a bare floor, that maybe sucking what heat it has out. And no wild yeast would not challenge your 1118

Julie: I think the OP said he has kept the wine at 23.3C which would be just a tad under 74F.

olusteebus, I agree with the bare floor sucking the temperature from the wine though as It does it to me if I set it on my cement floor. In any event warming the wine should always be the first step in a stalled ferment.

At 1.030 it may just be running so slow that you cannot see the bubbles breaking the surface of the wine. Getting a light shine on the surface will give it away. 1118 has a temperature tolerance of between 45 and 95 if it is stuck I would get it toward the upper limits around 85F and give it a good stir.

 

[BernardSmith]

The only times I have had stuck fermentations are when I have tried to ferment jams and then only when they had high fructose corn syrup. That may be a coincidence ... but I suspect that there is something about HFCS that inhibits fermentation. Could it be the way that HFCS is made makes it a challenge for yeast to ferment? The question then is , was your jam made with HFCS?

My other thought is that blackberries are by nature quite acidic. Could the pH have dropped to about 3.0 - a level that yeast dis-prefer? Might increasing the alkalinity of your wine (adding K-carbonate or Ca-Carbonate) restart the process?

 

[olusteebus]

I have gone back and found that most of my stuck ferments involved blackberry jam. I like using it because it was so easy to get.

Stupid, I will not do that again, I will use concentrate or maybe the fruit next summer.

 

[Turock]

olusteebus----You know, even tho you're using a good schedule with your nutrient, something you might want to pay more attention to is how the ferment is rolling along at that 1/3 break. If the ferment is sort of sluggish and not very warm at that point, you might want to add a dose of DAP at that point. That will help it finish up strong.

 

[olusteebus]

It was going great at the 1/3 depletion. I added fermaid k per instructions.

I may add K carbonate

 

[seth8530]

Does the wine taste sweet at 1.030? I am asking because it is important to remember that the hydrometer does not measure sugar, it measures density. It might be possible for excessive pectin from the jam to be causing the density to reach a high value even though the sugars are depleted.

 

[olusteebus]

I will taste today.

 

[grapeman]

I would not blindly add potassium carbonate. Unless the wine has way too much acidity it will do nothing to restart a stuck fermentation. Read the label on the jam jar and see if it had sorbate or other preservatives in it.

 

[olusteebus]

Ingredients
blackberries, high fructose corn syrup, corn syrup, fruit pectin, citric acid.

 

[wpt-me]

My last gallon batch I managed to get sg down to 1.014. The first time I tried it got stuck at 1.030 managed to restart and ended at 1.026.

Bill

 

[olusteebus]

I tasted a small amount and it does not taste like a sg of 1.030. I racked it, rehydrated some 1118 and added it. we will see soon.

 

[olusteebus]

I pitched 1118 again and it fermented some more. I only went down to 1.020 from 1.030 but at least I knew it was fermenting.

I am thinking Seth may be right. I tasted it and it does not seem to be at 1.020 sg taste wise. It is not completely dry but it tastes more like 1.005 or so to me. It is darn good. I topped up with merlot and stabilized. I will rack again in a week or so and then let it set for a few months. I think it will be really good.

But, I don't think I will make blackberry jam wine again. Thanks for all the help folks.