# Tips on icewine



## CarlD (Jan 13, 2016)

I have buy icewine must from a local grower and i'm looking for tips for fermentation . I have 37 brix and i have buy lalvin R2 yeast . 
Who have already make icewine with grapes ? 
Should i make a starter ? 
What dosage of yeast and fermaid K ?
What temp to ferment ?

Thanks


----------



## Treeman (Jan 15, 2016)

I've had good fermentation using this approach.
1. Rehydrate 5-8 g yeast with goferm for 3 gal juice with a full dose nutrient.
-I also add 300 mg/L lysozyme to juice to keep bacteria populations down
2. Add yeast to 2 c juice at room temp, 65-70F
3. Every 12-24 hrs double the volume of juice until all in one container.
4. Move to 50-55 F until fermentation is done.
5. Add Kmeta and drop temp to 0-20F until clear.
6. Rack and add Ksorbate.
7. Wait....wait....wait some more and then clarify if needed.


----------



## CarlD (Jan 15, 2016)

Thanks Treeman for the info . 
What yeast strain and grape you use ?
I never use lysozyme on wine , they can slow down the yeast ?
In step 2 , how much must you add to yeast ? 
How much the fermentation last ?


----------



## Runningwolf (Jan 15, 2016)

Treeman said:


> I've had good fermentation using this approach.
> 1. Rehydrate 5-8 g yeast with goferm for 3 gal juice with a full dose nutrient.
> -I also add 300 mg/L lysozyme to juice to keep bacteria populations down
> 2. Add yeast to 2 c juice at room temp, 65-70F
> ...



1. I'm a little confused here. If you're using goferm in your yeast starter (which I agree with) why are you adding a full dose of nutrient at the same time?

3.Why are you waiting every 12-24 hours to make additions to your starter rather than every 15 minutes as recommended by manufacturers.

4. Cooler temps for white fermentations is good but too cool could also hinder it. Plus if you kept doubling you yeast starter every 24 hours isn't your fermentation going to be nearly completed by the time you stick it in a 55° area? 

At what point are you adding the meta and putting in in a deep freeze? Zero brix, ten brix, etc.? I assume you're using carboys, how is that working out at that temperature and how long are you keeping them in that temp?

5.How much meta and where can you get to -20°? I add 100ppm and chill it to 30°F for a few weeks then filter with a .45 micron filter

6. Why are you adding Sorbate? Are you adding additional sugar?

I'm just curious as you may ferment more ice wine or faux ice wine then myself and I am interested in hearing more.


----------



## Treeman (Jan 16, 2016)

CarlD said:


> Thanks Treeman for the info .
> What yeast strain and grape you use ?
> I never use lysozyme on wine , they can slow down the yeast ?
> In step 2 , how much must you add to yeast ?
> How much the fermentation last ?




For yeast, I've used RHST, QA23, and encapsulated pro-dessert(BA11). I want to try sauterne yeast sometime. I've made faux icewine from muscat, chenin, riesling, and apple cider. This season, I'm going to try some Vignoles. 

Lysozyme can't hurt the yeast, it just keeps some bacteria from growing including those for MLF. I add the must step-wise see more info in next post. Fermentation has taken from 3-4 weeks.


----------



## Treeman (Jan 16, 2016)

Runningwolf said:


> 1. I'm a little confused here. If you're using goferm in your yeast starter (which I agree with) why are you adding a full dose of nutrient at the same time?
> 
> 3.Why are you waiting every 12-24 hours to make additions to your starter rather than every 15 minutes as recommended by manufacturers.
> 
> ...



Good questions, I was trying to keep the first post short and left out some details. I'm still learning as I go with icewine, but have 4 ferments done and will be starting 2 more soon once the basement cools off some more.

1. Good catch on nutrient, I don't add nutrient until all of the juice has been added stepwise to the ferment.

3. I follow the goferm rehydration instructions and add 1/2 volume of juice (~75 mL) after 15-30 min, then after another ~30 min add this mix to 2cups of juice. At this point, I wait 12-24 hrs before doubling the ferment volume. Typically as soon as I see good foam being produced, I add in the next step of juice. This step-wise addition is recommended in Daniel Pambianchi's book and I think it allows a healthy population of yeast to get going and adjusted to the high brix of the juice.

4-5. Fermentation is slow with this high of brix. Within 2-3 days it is moving to colder temps and brix might have fallen from 40 to 36. I think the goal is to get the population actively fermenting before challenging them with the colder 55 temp.
Ferments have been taking 3-4 weeks to finish. At this point there is no activity in the airlock and the brix (refractometer measured) is 24-27. I add 50ppm kmeta and but in a very cold fridge between zero-twenty degrees (not -20)...that would likely break glass :0).

6. I am adding 100 ppm sorbate as a precaution against fermentation starting again. When these stop fermenting, there is still plenty of sweetness left since the yeast I use typically stall out.


----------



## Runningwolf (Jan 16, 2016)

Ok that makes a lot more sense to me. Still laughing at the -20°. The only thing I would suggest is dropping the sorbate. I don't think it's doing a thing for you except giving you an off taste that will come out in about a year. Are you freezing the grapes and pressing or freezing the juice. I've seen people do it both ways.


----------



## Treeman (Jan 16, 2016)

Runningwolf said:


> Ok that makes a lot more sense to me. Still laughing at the -20°. The only thing I would suggest is dropping the sorbate. I don't think it's doing a thing for you except giving you an off taste that will come out in about a year. Are you freezing the grapes and pressing or freezing the juice. I've seen people do it both ways.




I've been freezing juice buckets. I will try dropping the Sorbate on the next batch. I'm sensitive to the "bubble gum" flavor of too much Sorbate and have found some references to 135ppm as the sensory threshold, so I've tried to keep it below that at 100ppm for my backsweetened and desert wines.


----------



## Hokapsig (Dec 21, 2016)

interesting guys...

I will be picking up some Vidal Ice juice next week in Erie and spoke with the winemaker who told me to use K1 or 1112 yeast, add double the yeast with nutrient and the alcohol production should kill the yeast. the juice is starting at around 40 brix. She told me to drop the temp once I get the taste that I want and sulfite AND to sorbate (shocked me too). 

Juice is pricey for me, but we will attempt 10 gal and see if we can make a profit with this. If not, I'm going to gain some expensive experience....


----------



## Johnd (Dec 21, 2016)

Hokapsig said:


> interesting guys...
> 
> I will be picking up some Vidal Ice juice next week in Erie and spoke with the winemaker who told me to use K1 or 1112 yeast, add double the yeast with nutrient and the alcohol production should kill the yeast. the juice is starting at around 40 brix. She told me to drop the temp once I get the taste that I want and sulfite AND to sorbate (shocked me too).
> 
> Juice is pricey for me, but we will attempt 10 gal and see if we can make a profit with this. If not, I'm going to gain some expensive experience....



I'm certainly no icewine expert, but it sure would seem that if the yeast is allowed to max out the alcohol content, there'd be no threat of renewed fermentation, and hence, no need for sorbate. But that's just my thought....


----------



## drainsurgeon (Dec 21, 2016)

Johnd said:


> I'm certainly no icewine expert, but it sure would seem that if the yeast is allowed to max out the alcohol content, there'd be no threat of renewed fermentation, and hence, no need for sorbate. But that's just my thought....



That was my first thought too, but I checked the yeast chart and it says Lalvin RC212 (I think that is the yeast he is using) has a temp range of 59-86 degrees. If you lower the temp to 55 to finish ferment (like Treeman suggests), it might stall out. When the wine warms back up it might just take off again, hopefully not in the bottle. Not sure I understand or agree at lowering the temp until fermentation is done, and sorbate doesn't kill the active yeast cells, it just keeps them from having kids.

I do have a question though. Am I making ice wine every time I freeze my fruit before starting a batch?


----------



## Johnd (Dec 21, 2016)

drainsurgeon said:


> That was my first thought too, but I checked the yeast chart and it says Lalvin RC212 (I think that is the yeast he is using) has a temp range of 59-86 degrees. If you lower the temp to 55 to finish ferment (like Treeman suggests), it might stall out. When the wine warms back up it might just take off again, hopefully not in the bottle. Not sure I understand or agree at lowering the temp until fermentation is done, and sorbate doesn't kill the active yeast cells, it just keeps them from having kids.
> 
> I do have a question though. Am I making ice wine every time I freeze my fruit before starting a batch?



Didn't catch the temp drop stalling out the yeast, one of the posts mentioned (hokapsig) the alcohol killing off the yeast, but that was a different suggestion.


----------



## Hokapsig (Dec 22, 2016)

The issue then would be the burn factor from all the alcohol created. there would be a long time for the burn to subside, but I agree if the yeast doesn't have anything to digest, no refermentation can take place, however, at 35 to 40 brix, the yeast can't survive to dry.


----------



## Treeman (Dec 23, 2016)

Hokapsig said:


> The issue then would be the burn factor from all the alcohol created. there would be a long time for the burn to subside, but I agree if the yeast doesn't have anything to digest, no refermentation can take place, however, at 35 to 40 brix, the yeast can't survive to dry.




ICV-K1 looks like an interesting yeast because it is so resilient to stressful conditions. My only concern would be getting the fermentation to stop when the alcohol, acidity, and residual sweetness are in balance. This yeast is suppose to be good up to 18% abv. At that high abv you are approaching port strength and potentially not enough sweetness to balance the heat. Most desert wines that I enjoy are 13-15%.

I also think it is important to clarify the wine at cold temps before adding the sorbate. Once the wine is clear and racked, the yeast population is much smaller, so adding some sorbate (birth-control) should be more effective and could be used at a lower dose.



drainsurgeon said:


> That was my first thought too, but I checked the yeast chart and it says Lalvin RC212 (I think that is the yeast he is using) has a temp range of 59-86 degrees. If you lower the temp to 55 to finish ferment (like Treeman suggests), it might stall out. When the wine warms back up it might just take off again, hopefully not in the bottle. Not sure I understand or agree at lowering the temp until fermentation is done, and sorbate doesn't kill the active yeast cells, it just keeps them from having kids.
> 
> I do have a question though. Am I making ice wine every time I freeze my fruit before starting a batch?




To be called "Ice wine" (Eiswein) grapes need to be harvested and pressed frozen. This process leaves water behind as ice and results in a high ~30-40 brix juice. It is expensive as Hokapsig already noted. Frozen grape must is just that if you thaw it completely. If you only partially thaw the must to increase the brix, this is what I do with grape juice but prefer to call it Faux ice wine, or vindeGlacier to recognize that this process is artificial compared to grapes freezing on the vine after a long hangtime in the vineyard.

IC


----------



## Hokapsig (Dec 23, 2016)

I need to keep the ABV below 14% or my tax rate changes. I will shoot for 12 to 14 via the SG method or I can pull out the ebulliometer. I will be vigilant on a daily basis to see where the brix is and to taste when it gets close. I don't want the alcohol burn, but do want the sweetness and flavors....


----------



## Hokapsig (Dec 23, 2016)

drainsurgeon said:


> That was my first thought too, but I checked the yeast chart and it says Lalvin RC212 (I think that is the yeast he is using) has a temp range of 59-86 degrees. If you lower the temp to 55 to finish ferment (like Treeman suggests), it might stall out. When the wine warms back up it might just take off again, hopefully not in the bottle. Not sure I understand or agree at lowering the temp until fermentation is done, and sorbate doesn't kill the active yeast cells, it just keeps them from having kids.
> 
> I do have a question though. Am I making ice wine every time I freeze my fruit before starting a batch?


 
You decrease the temp to stop the fermentation where you want it (per the taste or flavors you desire). then, once the yeast is stopped, sulfite and sorbate to stop refermentation in the bottle.


----------



## drainsurgeon (Dec 24, 2016)

Hokapsig said:


> You decrease the temp to stop the fermentation where you want it (per the taste or flavors you desire). then, once the yeast is stopped, sulfite and sorbate to stop refermentation in the bottle.



Lowering the temp, sulfiting and adding sorbate does NOT kill the active yeast. Some people refrigerate or actually freeze the gross lees and use it to start another batch of wine. I have done it myself. Lowering the temp just puts the yeast cells to sleep. Sulfiting is no guarantee that some of the active yeast cells won't wake up once warm and start fermentation again. Sorbate just keeps yeast cells from reproducing, it does not kill them. This has been discussed here many times so if you want to be sure the yeast is done, let the ferment finish and then back sweeten to your desire.


----------



## Treeman (Dec 25, 2016)

drainsurgeon said:


> Lowering the temp, sulfiting and adding sorbate does NOT kill the active yeast. Some people refrigerate or actually freeze the gross lees and use it to start another batch of wine. I have done it myself. Lowering the temp just puts the yeast cells to sleep. Sulfiting is no guarantee that some of the active yeast cells won't wake up once warm and start fermentation again. Sorbate just keeps yeast cells from reproducing, it does not kill them. This has been discussed here many times so if you want to be sure the yeast is done, let the ferment finish and then back sweeten to your desire.




Sorbate does more than just stopping reproduction. It effectively shuts down metabolism so the yeast can not use the residual sugar. This is the same way Sorbate inhibits refermentation in a wine that is made dry and then back sweetened. If Sorbate isn't added then refermentation can occur.

The residual sugar in ice wine is a quite different beast than a sweet wine that makes back sweetening an ice wine a challenging option. A sweet wine (spatlese riesling, 40g/L, 4 brix) can be made by adding 10% of a sweet reserve or sugar to a dry fermentation and result in only diluting abv by 10%. Ice wine on the other hand can contain 200g/L (20 brix) or more of residual sugar. A sweet reserve of juice typically could be 40brix and so it would have to dilute the dry wine by 50% to get to sweetness of 20brix. This would also dilute the abv of a dry 13% wine by 50% resulting in a 6-7% abv desert wine after dilution. So unless you started with a dry 26-30% abv wine before adding the sweet reserve your abv will be too low for a stable and balanced wine. And if you did take this back sweeting approach, you would still need to add Sorbate to the back sweetened wine, or sterile filter, or pasteurize to keep yeast from refermenting.


----------



## drainsurgeon (Dec 25, 2016)

Treeman said:


> Sorbate does more than just stopping reproduction. It effectively shuts down metabolism so the yeast can not use the residual sugar. This is the same way Sorbate inhibits refermentation in a wine that is made dry and then back sweetened. If Sorbate isn't added then refermentation can occur.
> 
> 
> 
> ...


----------



## Treeman (Dec 26, 2016)

As I said above, ice wine is a different beast than making a dry white and then back sweetening. When I make sweet riesling or gewurtz, I absolutely make it dry first then add Sorbate after it clears and then back sweeten.

With ice wine you essentially have a "stuck-fermentation" when the wine gets to 13-15% alcohol and still has 20+ Brix of residual sugar, so stopping it is not much problem by putting it in a fridge near 0° and hitting it with some Kmeta. This is one reason to use a yeast that is more susceptible to low temps and lower alcohol levels. Once the cold wine clears, then the number of yeast cells is small enough that addition of Sorbate to keep the few hardy mutants from doing any reproduction and any more fermentation, and you are good to go. This year I also plan to bottle some without Sorbate as suggested by Running Wolf above.


----------



## drainsurgeon (Dec 26, 2016)

I agree with you Treeman, that the ferment will stop because of alcohol poisoning if there is enough sugar in the must (high brix). My original point (in post 11) was that lowering the temp below the range of the yeast will probably "stall" the ferment BEFORE it is complete, not from alcohol poisoning. It WILL start again (maybe in bottles). Your statement: (Sorbate does more than just stopping reproduction. It effectively shuts down metabolism so the yeast can not use the residual sugar) is not correct. Read the article from EC Kraus. Ed clearly states that there is no practical way to successfully stop a fermentation as you were suggesting in post #18 and 20.

I just don't want vintner's out there thinking that they can throw in some kmeta and sorbate to stop a fermentation. They will be making potential bottle bombs. Wait for the ferment to finish, be it from running out of sugar or from high alcohol, it doesn't matter. Then sulfite and sorbate and back sweeten if desired.


----------



## Treeman (Dec 28, 2016)

I think we do agree on best practices for making a back sweetened wine. I also don't want folks using Sorbate the wrong way, but the EC Kraus info is a broad generalization about how Sorbate works for wine yeast. I'm not trying to stir the pot here, just sharing info. There are many articles about the biochemical effects of Sorbate on yeast. Here is one on metabolism changes. https://www.ncbi.nlm.nih.gov/pubmed/8386922

It is likely these metabolic changes and other enzyme inhibitions that result in a loss of yeast reproduction.


----------

