Potassium Bicarbonate/cold stabilization basic questions

[stickman]

Freezing is just a quick attempt at getting as much precipitation as possible.

"As ice formation increases, there is an increase in the relative concentration of all species in the sample, including alcohol, thus enhancing nucleation and crystallization."
1988 Bruce Zoecklein, Extension Enologist, Virginia Polytechnic Institute

 

[NorCal]

Tasted my samples. I went from the tasting the 0 to the 1.5 g/l addition and noticed the difference right away. I liked the 1.5 the best. Same with the Mrs. Did it blind, same results. I’m really happy that this has changed a wine that I think is not appealing to something I’d be proud to share/enter in a competition.

Time is on my side and I have around 25 gallons of this wine. I think I’ll repeat the experiment, make a half case, share some, leave some in the fridge for a while and make sure it is stable and the taste profile doesn’t change, before bottling the balance.

 

[Johnd]

Tasted my samples. I went from the tasting the 0 to the 1.5 g/l addition and noticed the difference right away. I liked the 1.5 the best. Same with the Mrs. Did it blind, same results. I’m really happy that this has changed a wine that I think is not appealing to something I’d be proud to share/enter in a competition.

Time is on my side and I have around 25 gallons of this wine. I think I’ll repeat the experiment, make a half case, share some, leave some in the fridge for a while and make sure it is stable and the taste profile doesn’t change, before bottling the balance.
View attachment 53194

Gotta love a successful bench trial!!

 

[ibglowin]

So what is he pH now of the 1.5g/l addition sample?

This is pretty weird that you prefer the sample with more than likely the highest pH and more than likely a pH closer to its initial starting point of 4.0

White wines usually are better with lower pH's down in the 3.1-3.4 range so perhaps this is just your palette or a Viognier thing?

All I can say is very interesting results!

Tasted my samples. I went from the tasting the 0 to the 1.5 g/l addition and noticed the difference right away. I liked the 1.5 the best. Same with the Mrs. Did it blind, same results. I’m really happy that this has changed a wine that I think is not appealing to something I’d be proud to share/enter in a competition.

Time is on my side and I have around 25 gallons of this wine. I think I’ll repeat the experiment, make a half case, share some, leave some in the fridge for a while and make sure it is stable and the taste profile doesn’t change, before bottling the balance.
View attachment 53194

 

[NorCal]

So what is he pH now of the 1.5g/l addition sample?

This is pretty weird that you prefer the sample with more than likely the highest pH and more than likely a pH closer to its initial starting point of 4.0

White wines usually are better with lower pH's down in the 3.1-3.4 range so perhaps this is just your palette or a Viognier thing?

All I can say is very interesting results!

Starting pH was 3.5 on the Viognier (I referenced 4.0 wines as something I’m usually dealing with and it is with my 26 brix reds) It still has some acidity. I need to replace the batteries on my meter when I get back into town. I’m comfortable with a higher pH, if it results in a lower TA and less acidic taste on the backend.

 

[GreginND]

Generally I prefer to do acid adjustments pre-ferment if possible. But if you must. FYI - I would kill to get my pH as high as yours with our cold climate grapes!

Anyway, deacidificaiton can lead to chalky flavors, so be a little careful. Generally not recommended to adjust the TA more than 1 g/L. The chemical reaction will occur immediately. But keep in mind you are adding some potassium ions along with the bicarb. Thus, your potassium balance will be changed and it is usually recommend that one cold stabilize after adding potassium salts if you are concerned about more tartrates forming in the bottle later. You can chill a sample to see if it is cold stable or not.

As always, go by TASTE not numbers.

 

[Ajmassa]

Holy crap, I think I just fixed my wine!

Between .6g/L and 1g/L addition it’s looking like after trials. Both a world of difference. Completely brought it back, rounding the whole thing out. Samples were frozen/thawed twice.
Control was 3.5ph .6g/L was 3.6ph. And the 1g/L was 3.8ph.
Not sure how to account for how CS precipitate will additionally affect it tho. Leaning towards .6 and hoping CS carries it across the finish line. Too much it seems would take “the umph” away- the wine’s “pizazz”. 1g/L was more flat, or boring. (Made an additional 1.5g/L sample to confirm) I don’t know how to describe it. I do know I’m very happy with the results.

 

[stickman]

@Ajmassa5983 Looks like you got some good precipitation there!

 

[ibglowin]

 

[Ajmassa]

What’s your opinion of the ph movement after the CS and the 3.65 threshold?
Like, is that a hardfast rule or just a possibility that can change from different variables?
And also, I realize each wine is unique, but on average how drastic does the additional tartrate precipitating further alter the taste ?
Thinking I’ll also steal @Norcal’s plan to first do a case to confirm before dosing and CS entire batch.

 

[ibglowin]

I think there are so many variables that its just place holder most of the time. I would not be in any hurry to bottle. Let it CS in a cold basement, outside or a fridge for at least a month. One of the worst wines I ever tasted was a commercial Cab Sauv from a local NM winery that I bought and took down to some friends for a special occasion. I paid like $23 for that bottle and upon opening and tasting it the overwhelming thing you tasted was salt. It was pretty obvious that they had perhaps added too much acid and then tried to fix it and did not allow it to stabilize and fall out of solution. It was chalky salted mess. Just horrible and we had to pour it out.

Like most everything in winemaking patience is a virtue.

What’s your opinion of the ph movement after the CS and the 3.65 threshold?
Like, is that a hardfast rule or just a possibility that can change from different variables?
And also, I realize each wine is unique, but on average how drastic does the additional tartrate precipitating further alter the taste ?
Thinking I’ll also steal @Norcal’s plan to first do a case to confirm before dosing and CS entire batch.

 

[Ajmassa]

I think there are so many variables that its just place holder most of the time. I would not be in any hurry to bottle. Let it CS in a cold basement, outside or a fridge for at least a month. One of the worst wines I ever tasted was a commercial Cab Sauv from a local NM winery that I bought and took down to some friends for a special occasion. I paid like $23 for that bottle and upon opening and tasting it the overwhelming thing you tasted was salt. It was pretty obvious that they had perhaps added too much acid and then tried to fix it and did not allow it to stabilize and fall out of solution. It was chalky salted mess. Just horrible and we had to pour it out.

Like most everything in winemaking patience is a virtue.

Thanks for the insight. When I added 1.5g/L and 2g/L samples just to have a better sense of how the taste is effected by acid removal I definitely noted the chalkiness you mention.
It helped in knowing what to be aware of coming through when dialing in the preferred dose.
It’s one thing to read about acid removal (there’s no shortage of literature out there), and a whole other thing to actual do it. I really did not understand the full scope of what the acid does for the wine until now

 

[NorCal]

Let it CS in a cold basement, outside or a fridge for at least a month.

Excellent advice, thanks, I will do that.

 

[NorCal]

Made full containers (27 gallons) and bottled 4 bottles for the fridge with 1.5 g/l bicarbonate. I’ll see if I have the patience to wait a month. I did try the remaining sample (3 days in fridge) and it was spot on. I tasted the non treated and it is such a different wine with the acid reduction.

 

[NorCal]

Not to leave good enough alone, I opened up one of the bottles. Yes, it’s only been a day, 29 days short of the month. However, I saw crystals at the bottom of the bottle and I knew something was happening. I am totally satisfied with the resulting taste of the wine. The flavor profile is of fine pear juice, which I think is the essence of Viognier. I added 1.5 g/l bicarbonate (corrected) to 11.5 of my 27 gallons. Feeling confident I’m on the right path.

 

[GreginND]

I hope you meant bicarbonate. I don't think I'd want to drink the biphosphate given its affects on the digestive track.

 

[NorCal]

Good news. The bottles in the fridge look stable. I measured pH between 3.6 and 3.7, which is high for a white, but the Viognier’s that I’ve had aren’t particularly tart.

 

[Ajmassa]

Having some trouble getting these carboys cold enough for CS. The daily temp swings are keeping them high 40°’s - 50°.
I have em insulated
in a 40° garage right by the door too. The next week or so it’s supposed to have lows in the 20°s. Removed the gas cans from the shed and airing it out gonna move em there hoping to get em <40°.
Otherwise I can freeze em one at a time. It’s 4 carboys total. Thoughts/suggestions?

 

[Boatboy24]

Leave 'em exposed at night, then cover them in the morning.

 

[mainshipfred]

Seems about all you can do except for the one at a time option.