Trouble with fermentation-What to do?

[Pauly2275]

I started a Zinfandel on Nov 11th. It's brix was 25 and I let it warm up to room temp before pitching the yeast. Within 11 days I began to notice the fermentaion had slowed considerably and it was not at the 1.000 range that I was hoping for. within 3 days I noticed that the fermentation had slowed to nothing more than the odd bubble in the juice and the specific gravity hadn't changed either. At this point I decided to siphon off a little to see how it tasted and wasn't surrised that it was a little on the sweet side for my liking.

At this point I decided to look into ways to re start the fermentation and found some advice that adding some yeast nutrient couldn't hurt, so I added some. I noticed initially some foaming as I added it and over the next day or two a slight increase in bubbling, so I had hope that I was back on track.

I have noticed that the fermenation has slowed down again and that the specific gravity has changed, but very little.

When I open the lid of the bucket I observe around 5 bubbles rising to the top over a 10 second period.

I have also read after adding the Yeast nutrient that any leftover nutrients can act as food for spoilage germs, is this true? and is there a way to sterilize it so the yeast nutrient will not aid spoilage?

What should my next course of action be with this wine to ensure a proper fermentation?

as it sits right now the specific gravity is 1.002 and I would like to have it in the .996-.998 range.

Thanks

Paul

 

[mmadmikes1]

Have you rack into a secondary yet?. Keep it warm(72 to 78). I have added yeast nutrients all the way though to wine with no ill effects so I would not have any problem adding some to this wine. What was your starting SG? What is your PH? Adding a some lemon juice will lower PH . Yeast like acid. I ferment at 3.6

 

[Pauly2275]

Have you rack into a secondary yet?. Keep it warm(72 to 78). I have added yeast nutrients all the way though to wine with no ill effects so I would not have any problem adding some to this wine. What was your starting SG? What is your PH? Adding a some lemon juice will lower PH . Yeast like acid. I ferment at 3.6

I have not racked to secondary yet and I've maintained it at a proper temp the entire fermentaion.

the original specific gravity was somewhere slightly above 1.100.

I don't have a ph tester, but maybe I should get one. The Yeast nutrient I added had dap, so it should have improved the ph I am guessing?

 

[djrockinsteve]

If you had or were able to get it add a teaspoon of super ferment. Give it a good stir to release co2 and give the yeast a little air. Don't whip it. Start off slow stirring at first. Co2 can rise fast.

Immediately after doing this snap on a lid with airlock or leave one snap open for co2 to escape. Gravity should drop in 2 days.

 

[tjbryner]

If you had or were able to get it add a teaspoon of super ferment. Give it a good stir to release co2 and give the yeast a little air. Don't whip it. Start off slow stirring at first. Co2 can rise fast.

Immediately after doing this snap on a lid with airlock or leave one snap open for co2 to escape. Gravity should drop in 2 days.

I checked 2 or 3 place that I order from and have yet to find super ferment. Were do you get it from?

 

[Brintk]

I'm wondering what yeast you used. Based on the info that you supplied (Starting Brix 25, Current S.G. 1.002), your wine now stands at slightly over 14% alcohol (Based on "FermCalc" tables.). Depending on the yeast that you initially pitched, you may have reached it's max. alcohol potential.

You could try making a yeast starter, using a yeast like EC-1118, and pitching that to restart the fermentation.

 

[saddlebronze]

Assuming the wine is essentially done fermenting, I would rack to secondary with the lees, put an airlock with some meta solution in the airlock and watch it for a day. If it is not bubbling more than a few bubbles a minute, I would rack it to another secondary, dose it with meta and start fining and bulk aging.

 

[Pauly2275]

I'm wondering what yeast you used. Based on the info that you supplied (Starting Brix 25, Current S.G. 1.002), your wine now stands at slightly over 14% alcohol (Based on "FermCalc" tables.). Depending on the yeast that you initially pitched, you may have reached it's max. alcohol potential.

You could try making a yeast starter, using a yeast like EC-1118, and pitching that to restart the fermentation.

Thank you! your comment got me wondering the alcohol tolerance of the yeast I used. it was a 71b-1122 lalvalin, which has a tolerance of 14%. It makes me wonder why the company that sold me the juice gave me that yeast fully knowing that the Zinfandels tend to be higher in sugars and could easily bump over the 14% mark.

Does anyone have a link to another thread about the proper way to start a yeast to add to an existing batch?

Thanks very much!

Paul

 

[Pauly2275]

Assuming the wine is essentially done fermenting, I would rack to secondary with the lees, put an airlock with some meta solution in the airlock and watch it for a day. If it is not bubbling more than a few bubbles a minute, I would rack it to another secondary, dose it with meta and start fining and bulk aging.

I was thinking the same as you, but after tasting it I simply cannot. I like my wines on the dryer side and the taste of sugar kind of puts me off a little. There isn't much sugar left, but even at .002 it's noticable.

 

[djrockinsteve]

Go to the home page here. We have a tutorial section to help you with many things.

Super Ferment is a "Yeast Energizer". The places you call may have that under a dig. name.

Reading above if you are around 14% ABV then yes rack to a Carboy and either let it sit under airlock a week or two or I would proceed to stabilize and clear.

The Lalvin yeast they gave you is a great yeast. there is also a tutorial on yeasts as well.

 

[mmadmikes1]

Rack to carboy either way. The airlock can still bubble even when fermentation has stopped. It will be de gassing. Air bubbles are not a good indicator of fermentation. If you don't like wine that sweet you may need to blend. At 14% it will be hard as hell to get fermentation of any yeast besides turbo going and you probably will not like that result, taste wise. BTW I like that yeast for Zin, it helps keep the fruity taste. Alas, do not judge a wines taste early thinking that will be even close to finish taste

 

[Pauly2275]

Rack to carboy either way. The airlock can still bubble even when fermentation has stopped. It will be de gassing. Air bubbles are not a good indicator of fermentation. If you don't like wine that sweet you may need to blend. At 14% it will be hard as hell to get fermentation of any yeast besides turbo going and you probably will not like that result, taste wise. BTW I like that yeast for Zin, it helps keep the fruity taste. Alas, do not judge a wines taste early thinking that will be even close to finish taste

I have been reading about some clearing agents that when added will bond to sugar particles, thus removing some sugar from the wine if I understand correctly? I have found that the specific gravity is now making very small increments of change. Hopefully just a little more and I will be happy