backsweetening; refermenting issues?

[shanek17]

So I have succesfully done my first backsweetning...well almost succesfully.

So i made a 5 gal 11% welchs frozen grape wine and it fermented to an SG of .992. I also added 1/4 tsp of sulfites and then moved it to the basement for 1 month of bulk aging.

Then on august 22nd (which is 6 days ago from today) I added 2 cans of welchs frozen juice to the welchs 11% alcohol wine. I also added 4g of sorbate and 1/8 tea spoon of sulfites to help out. The sorbate and sulfites were purchased within the last 6 months from the LHBS. Now today on august 27th i brought the carboy from the basement which is 64F and brought it upstairs to a 75F room. I looked at the head space and noticed there wasnt very much, possibly because the liquid was getting warmer and expanding, but the actual head space was very minimal at 1/4 of an inch! I then opened up the solid rubber bung and it made a LOUD pop sound and made me jump pretty good! and I watched a bunch of bubbles continue to rise up for a little bit.

So what the heck is going on here? Is it refermenting in the carboy? or could this be a build up of pressure due to the little amount of head space and perhaps some co2 left in the wine. I also tested the co2 level in the wine by shaking a small amount in a jar and when i took the lid off it made a small pop sound and I did notice bubbles coming up. The weird thing is I degassed this wine upstairs at 75F for weeks and could have sworn I had it degassed plenty. I even racked it a couple times before putting it in the basement to help release co2.

 

[Deezil]

Honestly, i'd bet its both residual co2 from fermentation, and co2 from refermentation.

Theres a chance you may have backsweetened backwards (sugars before sorbate?) - if not, im pretty sure you backsweetened 'too soon'

By 'too soon', i mean, too soon after adding your k-meta and sorbate.. Personally, i wait a week after adding my sorbate & k-meta before i add the backsweetening sugars (some people wait a day, some people do it immediately after dosing out the chemicals, i do it how i do because it works for me) but the important part is to give the sorbate time to bind with the yeast present & keep them from budding/multiplying more..

If you want to add the sugars sooner rather than later, stir more (but dont oxidize, which is why i wait) to get the sorbate mixed around..

I think the sorbate didnt have enough time to find all the yeast so the yeast seen the sugars and kept eating until the sorbate found them.. Check your SG - is it the same that you backsweetened to? That'll tell ya

 

[southlake333]

Personally, i wait a week after adding my sorbate & k-meta before i add the backsweetening sugars

+1 to that. Since sorbate just keeps the yeast from reproducing, its better to add birth control, give it time to take effect, then give the newly snipped yeast time to die out. I give it 1 to 2 weeks (while its clearing).

 

[mmadmikes1]

It would go pop just because of the expansion of the wine when it warmed up. I always get a little pop because I never remove all the co2.(helps prevent Oxidation).

 

[shanek17]

Honestly, i'd bet its both residual co2 from fermentation, and co2 from refermentation.

Theres a chance you may have backsweetened backwards (sugars before sorbate?) - if not, im pretty sure you backsweetened 'too soon'

By 'too soon', i mean, too soon after adding your k-meta and sorbate.. Personally, i wait a week after adding my sorbate & k-meta before i add the backsweetening sugars (some people wait a day, some people do it immediately after dosing out the chemicals, i do it how i do because it works for me) but the important part is to give the sorbate time to bind with the yeast present & keep them from budding/multiplying more..

If you want to add the sugars sooner rather than later, stir more (but dont oxidize, which is why i wait) to get the sorbate mixed around..

I think the sorbate didnt have enough time to find all the yeast so the yeast seen the sugars and kept eating until the sorbate found them.. Check your SG - is it the same that you backsweetened to? That'll tell ya

yea i think your rite, some residual co2 and refermentation. I actually added sorbate and k meta to it and then did sugar additions, but i probably only waited 5 minutes before pouring in the sugar. I dont remember if I stirred the sorbate and kmeta once it was in there, but I think i did. But what confuses me here is this. if the sorbate takes time to bind to the yeast to keep them from multipying then why is the sorbate not working yet? its been 1 week since i added the sorbate so that should be enough time for them to work rite?

and just an update on the wine, after i pulled the bung off and heard the loud pop I put the solid bung rite back on there and then roughly half a day later I pulled the bung off and was suprised to hear that loud pop again! And when im looking inside the neck of the carboy there are alot of visible bubbles riseing up , so i think its safe to say its refermenting again....Its under an airlock now but where do i go from here?

I enjoyed the slightly sweet taste that the back sweetening did for this wine, but now it looks like the yeast are going strong and going to eat up all the sugar, leaving me with a dry wine again. (also I used a high tolerance yeast, possiblly the 1116 or 1118) I guess maybe ill have to do another back sweetening.

oh and about the hydrometer... I was so focused on doing the back sweetening good that i totally forgot about the hydrometer, so thats a mystery now. oh well I took a hydrometer reading now and its at 1.000, initially the OG was .992, so ill keep an eye on it and see if it will ferment to dry.

 

[loumik]

So I have succesfully done my first backsweetning...well almost succesfully.

So i made a 5 gal 11% welchs frozen grape wine and it fermented to an SG of .992. I also added 1/4 tsp of sulfites and then moved it to the basement for 1 month of bulk aging.

Then on august 22nd (which is 6 days ago from today) I added 2 cans of welchs frozen juice to the welchs 11% alcohol wine. I also added 4g of sorbate and 1/8 tea spoon of sulfites to help out. The sorbate and sulfites were purchased within the last 6 months from the LHBS. Now today on august 27th i brought the carboy from the basement which is 64F and brought it upstairs to a 75F room. I looked at the head space and noticed there wasnt very much, possibly because the liquid was getting warmer and expanding, but the actual head space was very minimal at 1/4 of an inch! I then opened up the solid rubber bung and it made a LOUD pop sound and made me jump pretty good! and I watched a bunch of bubbles continue to rise up for a little bit.

So what the heck is going on here? Is it refermenting in the carboy? or could this be a build up of pressure due to the little amount of head space and perhaps some co2 left in the wine. I also tested the co2 level in the wine by shaking a small amount in a jar and when i took the lid off it made a small pop sound and I did notice bubbles coming up. The weird thing is I degassed this wine upstairs at 75F for weeks and could have sworn I had it degassed plenty. I even racked it a couple times before putting it in the basement to help release co2.

shanek17,
It sounds to me as if your wine is giving off Co2. What method did you use to degass? If you put a solid bung in the carboy when you tried to degass, especially if you only left a 1/4" of head space it probably didn't degass. Degass again at 75*F and replace the solid bung with one with a hole in it and an airlock. Give it some time to degass, at warm temps before placing in the basement to age. Bulk ageing for 3-6 months would probably be a good idea, but keep the airlock filled. And as Deezil said you should have waited at least 2-3 days after putting in the sorbate before back sweetning. Good Luck and let us know how it's going.

LOUMIK

 

[mmadmikes1]

yea i think your rite, some residual co2 and refermentation. I actually added sorbate and k meta to it and then did sugar additions, but i probably only waited 5 minutes before pouring in the sugar. I dont remember if I stirred the sorbate and kmeta once it was in there, but I think i did. But what confuses me here is this. if the sorbate takes time to bind to the yeast to keep them from multipying then why is the sorbate not working yet? its been 1 week since i added the sorbate so that should be enough time for them to work rite?

and just an update on the wine, after i pulled the bung off and heard the loud pop I put the solid bung rite back on there and then roughly half a day later I pulled the bung off and was suprised to hear that loud pop again! And when im looking inside the neck of the carboy there are alot of visible bubbles riseing up , so i think its safe to say its refermenting again....Its under an airlock now but where do i go from here?

I enjoyed the slightly sweet taste that the back sweetening did for this wine, but now it looks like the yeast are going strong and going to eat up all the sugar, leaving me with a dry wine again. (also I used a high tolerance yeast, possiblly the 1116 or 1118) I guess maybe ill have to do another back sweetening.

oh and about the hydrometer... I was so focused on doing the back sweetening good that i totally forgot about the hydrometer, so thats a mystery now. oh well I took a hydrometer reading now and its at 1.000, initially the OG was .992, so ill keep an eye on it and see if it will ferment to dry.

Because sorbate does not kill living yeast. If the yeast is there and alive it will continue to digest sugars. As long as there is yeast alive and sugars to eat it is useless, IMO. The problem with a high Alcohol tolerance yeast is the stuff is tuff. That is why I tell people to pick yeast with alcohol tolerance at level you are wanting. Even if it restarts if dies quick.

 

[Deezil]

Sorbate doesnt kill living yeast, no... But it will bind-to living yeast, keeping them from making more yeast.. So then when the yeast that the sorbate bonded to, dies, you're safe - they'll eat a little bit more sugar before they die but not much

But i still wait a week, when i do use sorbate, before sweetening, to make sure its bonded to all the yeast

 

[ckassotis]

Sorbate doesnt kill living yeast, no... But it will bind-to living yeast, keeping them from making more yeast.. So then when the yeast that the sorbate bonded to, dies, you're safe - they'll eat a little bit more sugar before they die but not much

This is mostly true, but they will not necessarily stop quickly. Yeast don't die immediately upon converting x amount of sugar. If you add sorbate to an active fermentation, it will do nothing. You will already have a healthy population of yeast. While it will prevent those yeast from reproducing even further, those still there can and will continue to keep eating that sugar. Depending on your yeast population and its alcohol tolerance, it very well could eat through all of the new sugar.

 

[Deezil]

This is mostly true, but they will not necessarily stop quickly. Yeast don't die immediately upon converting x amount of sugar. If you add sorbate to an active fermentation, it will do nothing. You will already have a healthy population of yeast. While it will prevent those yeast from reproducing even further, those still there can and will continue to keep eating that sugar. Depending on your yeast population and its alcohol tolerance, it very well could eat through all of the new sugar.

Right, but i'd never add sorbate to an active fermentation... As mmadmike pointed out in another thread, the amount of sorbate it would take to do that would ruin the final product.. I'd never recommend it..

It's entirely true, if you follow the reasoning that you'd only add sorbate to a wine that is basically bulk aging... fermented, degassed, sometimes cleared or working on it..

 

[ckassotis]

I can't completely agree with that. You don't know how many dormant yeast are still sitting there waiting around. You're right in that it probably isn't too much. But if he didn't stir up the sorbate like he said, and then poured the sugar on top of it, it could have provided the yeast with some time to repopulate prior to being exposed to the sorbate.

Regardless though, even with just a few yeast, they aren't going to die off until conditions are no longer favorable to them. As long as the % alcohol stays below tolerance and there is plenty of sugar, even a small population isn't going to die quickly.