Blueberry wine harshness/pH help

[penguinluvinman]

Thanks to everyone who assisted me in my previous thread. I did get a large batch of around 60 gallons/220ish lbs of blueberry wine going, and I think it's proceeding pretty well so far.

We're on day 12 after inoculation, and my SG reading is finally at 0.998, so assuming it holds steady I'll probably rack it on Monday.

I've noticed some harshness in my tastings and it has some bite to it, so I've been thinking the acidity is a little high. I just got a pH meter in today, and my first reading came in at about 2.5. I have TA test coming as well but it has not arrived yet.

So now my question is on addressing the harshness or adjusting the pH before I rack it. From my research it seems like my best options would be to add some sodium/potassium/calcium citrate or bicarbonate, or possibly trying MLF.

Any advice on which of these would be the best option, or is there a better alternative? If adding citrate or carbonate as a buffer is the best move, is there any way to calculate how much I'll need, or should I just add a little at a time and keep checking?
I have a good bit of potassium bicarbonate on hand so if I could use it that would be ideal. It says that 3.4 grams will raise one gallon of wine by 0.1 pH, so using that math about 30 oz would get me up to around 3.2 pH.

I also know I need to add some tannin, which should also be arriving tomorrow (the curse of not having a local homebrew shop), so could that also have an affect to help on the acidic taste?

I don't know much about MLF, but is it as simple as pitching some new bacteria and letting it roll for another week or so?

Thanks again in advance for your advice!

 

[Rembee]

If it were me, at this stage I would adjust the ph with potassium bicarbonate. Rack it first off of the settlement and then you can adjust slowly to a ph of 3.4 to 3.6. Then place under an airlock. Since you now own a ph meter, the next time you make a batch of wine adjust the ph before pitching the yeast. Blueberries are very acidic and 2.5 is not uncommon with them.

 

[penguinluvinman]

If it were me, at this stage I would adjust the ph with potassium bicarbonate.

Cool thanks, I was hoping it would be that simple. I was definitely not expecting this problem, but I'm glad I have the pH meter now. The recipe called for acid blend, and I only added half what it called for specifically hoping to avoid this problem. I figured I could add more acid later when I had the meter. But I was getting worried from the taste tests once the sugar disappeared that it was already too acidic.

 

[Rembee]

Always test the ph of the must prior to adding other acids and before pitching the yeast. Even though your recipe called for acid blend you now know that you didn't need it. Especially with blueberries. I make blueberry wine every year from home grown and just the blueberries alone normally have a ph of 3.2 to 3.6. I never add acid to them.

 

[Johnd]

You can’t trust pH readings when you have CO2 present in your wine, and you have lots of it. Carbonic acid will give you a lower than actual reading. Warm a small sample into the 80’s and shake / release gas numerous times until your sample is degassed. If your pH is really in the 2.xx’s, bump it slowly into the lower 3.x’s. If you’re in the 3’s already, consider waiting a bit and adjusting after you’ve back sweetened.

As for making adjustments based upon taste of a few day old wine, my advice would be to wait. New wine is funky, green, disjointed, and sometimes bitter and nasty. As the chemical changes continue in your wine, it will evolve for the better, and then you’ll be in the appropriate time frame for adjusting based upon taste. Additionally, most blueberry wine is back sweetened, which brings out more berry flavors and overcomes bitterness.

 

[Raptor99]

Lots of good advice here. Ditto to adjusting the pH slowly, step by step. pH is logarithmic, not linear, so you can't really calculate how much potassium bicarbonate to add to raise the pH by X amount. It's best to adjust it a little bit at a time. For my 1-gallon batches, I add 1/8 tsp. at a time. Then mix it and let it set for 24 hours before measuring pH again.

 

[penguinluvinman]

You can’t trust pH readings when you have CO2 present in your wine, and you have lots of it. Carbonic acid will give you a lower than actual reading.

That's a good point I definitely didn't think about. I'll try to get a more accurate reading tomorrow using your method. The fermentation seems to be going well so maybe it isn't as bad as I was afraid. I started with a gravity of 1.082 and I'm down to 0.998 on day 12.

When does oxygen start to become the enemy? It's in a sealable vessel but I've been letting it breathe for primary. When I removed the blueberry pulp a few days ago I lost a lot of volume so there's a good bit of head space in the tank. It has a bottom valve I can drain the lees but that would create a lot more space also. I'm racking the large tank into a few 5 gallon buckets for secondary, so I need to mostly fix it before racking. My boss likes it pretty dry, but I prefer sweet so I'll do some varying amounts of sugar once they're separated. But the base batch needs to be solid before separating it out.

 

[Rembee]

O2 starts to become your enemy below sg 1.010 IMO. So racking it and getting it under an airlock is very advisable at this stage.
You mentioned 5 gal. buckets for your secondary. What type of buckets?
Because most fermenting buckets and or pails do not create a substantial seal for placing under an airlock. You would do much better racking into 5 or 6 gallon carboys with a fitted bung and airlock. Buckets just don't seal up tight enough even with a gasket under the lid. They eventually become pliable and will not hold a seal.

 

[Rice_Guy]

@Johnd suggested wait before making pH corrections. The CO2 will have dropped the pH so any reading today is suspect. I run TA with the pH meter. Titrate to pH 8.2 which is where phenothaleine changes color, ,,,, you are already dark blue so you would need to dilute 1/10 with distilled water to see a hint of color change. Yes sugar can balance high acid.
Adding acid assumes that you added water with 0% TA and have to compensate for this. 100% blueberry would be high TA.
when the wine stops actively flushing air out it needs to be under an air lock, or balloon or floating lid etc. There is ethyl alcohol in the wine which combines with oxygen producing acetaldehyde creating a burn the back of the throat flavor when you swallow. On my part I look at racking off lees with country wine and white grape after it is below 1.020 (still actively flushing CO2 ).
If you still have carboys use them! A bucket has a flat lid which means more volume in the ullage (head space) and more oxidation. If you read old posts they will say fill to the neck leaving only an inch of air. ALSO you need to keep 50ppm of free SO2 , if you don’t have a test you’re fairly safe saying it is at zero so just calculate 50ppm. ,,, The tank is still an option. The answer in this case is fill the extra head with a food grade poly bag that is inflated with inert gas as CO2 or a wine preserver.

 

[penguinluvinman]

TA test came today and measured at 8.4.

I added about 1/2 cup of bicarb total and the pH is right around 3.0 now so I'll leave it at that for the moment.

Our buckets are just 6 gal plastic ones with a lid and airlock but they're supposed to be made for brewing. We do have glass carboys as well, but I was planning to use them for the 2nd racking from the bucket in another few weeks

 

[Rembee]

It would be better to go ahead and rack into the glass carboys now. No matter what type of plastic bucket it is, even for brewing, it will not hold a seal. Buckets are only good for primary fermentation IMHO.

 

[Steve Wargo]

Thanks to everyone who assisted me in my previous thread. I did get a large batch of around 60 gallons/220ish lbs of blueberry wine going, and I think it's proceeding pretty well so far.

We're on day 12 after inoculation, and my SG reading is finally at 0.998, so assuming it holds steady I'll probably rack it on Monday.

I've noticed some harshness in my tastings and it has some bite to it, so I've been thinking the acidity is a little high. I just got a pH meter in today, and my first reading came in at about 2.5. I have TA test coming as well but it has not arrived yet.

So now my question is on addressing the harshness or adjusting the pH before I rack it. From my research it seems like my best options would be to add some sodium/potassium/calcium citrate or bicarbonate, or possibly trying MLF.

Any advice on which of these would be the best option, or is there a better alternative? If adding citrate or carbonate as a buffer is the best move, is there any way to calculate how much I'll need, or should I just add a little at a time and keep checking?
I have a good bit of potassium bicarbonate on hand so if I could use it that would be ideal. It says that 3.4 grams will raise one gallon of wine by 0.1 pH, so using that math about 30 oz would get me up to around 3.2 pH.

I also know I need to add some tannin, which should also be arriving tomorrow (the curse of not having a local homebrew shop), so could that also have an affect to help on the acidic taste?

I don't know much about MLF, but is it as simple as pitching some new bacteria and letting it roll for another week or so?

Thanks again in advance for your advice!

If not said already you should wait until you have degassed the wine before taking an acid reading. Yes, new wine tastes harsh and acidic. Best to use potassium bicarbonate to adjust the must pre-carbonation, wait. Time heals all, including acidity.

 

[penguinluvinman]

@Rice_Guy

My initial recipe had 225 lbs of blueberries and 40 gal of water if that helps. Based on your and @Rembee 's advice I think I will skip the buckets and go straight into carboys. I won't have enough for all of them for another racking, but I should have enough carboys to make it work even if I have to juggle them a little. SG held at 0.998 today, so I'll probably rack it tomorrow if it's still the same. I'm getting more worried about oxygen exposure now in the big tank since it won't be releasing as much CO2.

I do have some sulfite test kits, but not very many of them. Would it be better to take a reading for that now, or wait until later in the process? I used some k-meta initially before pitching the yeast and a little more when I pressed the blueberries because I was worried about contamination during that process.

 

[Rembee]

What most folks here do, including myself, is to add k-meta or potassium metabisulfite every 3 months during bulk storage. Even if you rack before 3 months has gone by to help with clarification, adding k-meta every 3 months is the norm.

 

[Rice_Guy]

if I had limited free SO2 tests I would assume that it is at zero now early in process and add 50ppm. Most people are uncontrolled and add disolved oxygen every time they move wine,,, where as commercial would flush with nitrogen or CO2
I would measure at bottle time and use the web calculator to get a accurate read for the end user. Some folks are sensitive and will taste high sulphites

I do have some sulfite test kits, but not very many of them. Would it be better to take a reading for that now, or wait until later in the process? I used some k-meta initially before pitching the yeast and a little more when I pressed the blueberries

 

[wood1954]

Speaking from experience if you add too much potassium bicarbonate your wine will taste kind of salty.

 

[subseageorge]

What most folks here do including myself is to add k-meta or potassium metabisulfite every 3 months during bulk storage. Even if you rack before 3 months has gone by to help with clarification, adding k-meta every 3 months is the norm.

Hi , How much potassium metabisulfite do you add every 3 months ?
Thanks

 

[Rembee]

@subseageorge, The recommended amount by most on this forum and by directions on the bag of metabisulfite are 1/4 tsp per 6 gallons. It is also ok to use 1/4 or a smidgen less then a 1/4 tsp in 5 gallons. If dosing 1 gallon, I use a smidgen of 1/8 tsp. Hence 1/8 tsp is good for 3 gallons, so I just eyeball 1/8 of a tsp divided by 3 for a gallon. Doesn't have to be exact.

 

[sour_grapes]

@subseageorge, The recommended amount by most on this forum and by directions on the bag of metabisulfite are 1/4 tsp per 6 gallons. It is also ok to use 1/4 or a smidgen less then a 1/4 tsp in 5 gallons. If dosing 1 gallon, I use a smidgen of 1/8 tsp. Hence 1/8 tsp is good for 3 gallons, so I just eyeball 1/8 of a tsp divided by 3 for a gallon. Doesn't have to be exact.

Another trick I use is to add 1/4 tsp. to 6 Tablespoons of water. Then add 1 Tbsp. of the solution to your gallon of wine.

 

[Raptor99]

Another trick I use is to add 1/4 tsp. to 6 Tablespoons of water. Then add 1 Tbsp. of the solution to your gallon of wine.

I use a small scale and measure the amount in grams. That way I can adjust the required amount of Kmeta depending on the pH.