Running tests on my first batch of raspberry wine

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sremick

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So I have 6 gallons of raspberry wine that I started bulk aging on 5/1. This represents my first attempt at making wine NOT from a kit, but just using raw ingredients. Today I ran some tests:

pH: 3.9
TA: 7.5 g/L
SO2: 46.4 ppm

From the charts I've seen, I'm a bit low on SO2 (should be between 62-98 ppm) and should add more. The middle # would be 80, which is a difference of 33.6. To add 33.6 ppm to 6 gal would mean 0.763 grams of potassium metabisulfite. Sound right?

Anything else I should be checking at this point?
 
So I have 6 gallons of raspberry wine that I started bulk aging on 5/1. This represents my first attempt at making wine NOT from a kit, but just using raw ingredients. Today I ran some tests:

pH: 3.9
TA: 7.5 g/L
SO2: 46.4 ppm

From the charts I've seen, I'm a bit low on SO2 (should be between 62-98 ppm) and should add more. The middle # would be 80, which is a difference of 33.6. To add 33.6 ppm to 6 gal would mean 0.763 grams of potassium metabisulfite. Sound right?

Anything else I should be checking at this point?

Check the taste, 3.9 pH is high, you should do some taste testing (bench trials) to see if the taste can be improved and pH lowered at the same time. If you can lower the pH, your sulfite management challenges will ease.
 
Thanks. I'm still honing my tasting skills... it doesn't seem horrible to me, but I think a lot of it is that it needs to mellow out with some aging. I'll get some additional opinions. I had tried to raise the pH pre-ferment so that the yeast had a change, but it seems fermenting raised it further. Some questions:

1) what would be a good target pH?
2) What acid would you recommend to lower the pH?
 
By 'raised' do you mean it went from like pH 3.4 down to pH 3.1 or something like that? That would be normal. CO2 and the fermentation process will do that. Don't worry too much for now. Give it at least 3-4 months after fermentation ends before checking it again.

3.9 is pretty high for wine - pre-ferment. Most times you want to be in the range of 3.4 to 3.6 before starting fermentation. I've seen at least one commercial wine labeled with a pH of 3.18 in the bottle.
 
I am struggling to find my notes for this batch, but my posts on this forum save the day. My starting pH was 3.5... I raised it from 2.5. I used up all the potassium bicarbonate at the time so I had to use some calcium carbonate to get it the rest of the way there. Because of all the potassium bicarbonate, I imagine I'm going to need to cold-stabilize this.

Also, my starting TA was 0.65

What acid would you recommend to lower the pH in cranberry wine?
 
Just wanted to check in again to see if it's recommended that I use citric, tartaric, or acid blend to adjust the acid before I then adjust sulfites. Thanks
 
This is cranberry wine? A different wine from the post topic of a high pH raspberry? Just checking.

Acid blend works fine for fruit wines. I’m confused as to why you went to great lengths to raise the pH, and then want to lower it back down. Wouldn’t recommend changing your acid post fermentation without tasting trials.
 
Holy crap... I just realized in this thread I've been typing "raspberry" the whole time, because I'm planning a batch of raspberry so that word has been on the brain. But I have not started that one yet!

This was actually meant to be about the cranberry wine I already made the whole. Ugh. Crap, I think I'm starting to get old and go senile...

To answer your question: I needed to raise the pH for the fermentation to take place. It started way too acidic for yeast. But now, post-ferment, it's too high.

You had suggested to fix (lower) my pH now (post-ferment) to make managing sulfite levels easier.
 
So it started at 2.5, you raised it to 3.5 and fermented, and it ended up at 3.9 and now you want to lower it?
Correct. AsI was looking at recipes, I was seeing that I should target a pH of 3.3-3.4 pre-ferment. pH 2.5 was way out of that, so I tried to fix that and hit 3.5, which I figured was close enough.
So now I hear that ph 3.9 is too high for sulfite management, and I should lower it. :-/

Please excuse me if this all seems idiotic and I messed up somehow. I'm trying as best I can as a newbie doing what research he can as he attempts his first batches of wine.
 
Correct. AsI was looking at recipes, I was seeing that I should target a pH of 3.3-3.4 pre-ferment. pH 2.5 was way out of that, so I tried to fix that and hit 3.5, which I figured was close enough.
So now I hear that ph 3.9 is too high for sulfite management, and I should lower it. :-/

Please excuse me if this all seems idiotic and I messed up somehow. I'm trying as best I can as a newbie doing what research he can as he attempts his first batches of wine.

I’m not picking, just making sure I understand where you are. You’ve depleted lots of acid from the wine, a lot more than you probably should with the two chems you used, so let’s go slow from here. Get your wine protected with sulfite ASAP. Give yourself some time to conduct some taste trials with acid blend, determine your desired endpoint, and work your way to it by adjusting the whole batch SLOWLY. Really slow, like over a few weeks, ease your way to the goal and taste to make sure you don’t overdo your dosing.
 
Ok I can do that tonight. It's not that there's no sulfite in there... just a bit less than the guidebooks suggest.

Going back to my first post, is my math (0.763 grams of potassium metabisulfite) correct?
 
Ok I can do that tonight. It's not that there's no sulfite in there... just a bit less than the guidebooks suggest.

Going back to my first post, is my math (0.763 grams of potassium metabisulfite) correct?

Add 1/4 tsp for your 6 to get it protected, let it clear and get a little age on it, then work on your trials.
 
"What acid would you recommend to lower the pH?"

In my wine club, people recommend using the acid that is predominant in the fruit, as shown here: http://www.brsquared.org/wine/CalcInfo/FruitInf.htm

But tasting is important, as others have noted. You might like the taste of ctiric more than malic for example.

I've always understood that it's best to use acid blend for fruit wines, and straight tartaric for grape wines. Doesn't mean that you can't do some variation of the blend if you wanted to add a little more of one kind or another.
 
What acid would you recommend to lower the pH in cranberry wine?
* Acids, for most of us tartaric is a good flavor acid, lactic is a mild flavor. malice and citric are described as sharp/ biting flavor. Normally I would add blend since it is available at the local shop.
* You have added a slug of potassium which will complex with tartaric so your chemistry will be complicated/ hard to predict. (it will change after day one when you think it is perfect) Think you said calcium carbonate which is slow to react so again it will change after day one.
* I would not correct pH above 3.1, white wine can be there, yeast is more tolerant than you think. , , , Some folks use a starter with cranberry so the yeast is actively growing. TA of straight cranberry is high, 30 to 32 per kilo fruit (roughly means per liter) You can run high TA as 10 or 10.5 per liter BUT you have to back sweeten more. Commercial cranberry cutsTA with water since that is a lesser cost ingredient. Me, I favor adding a low flavor higher pH fruit so the label says all fruit.
* My view is that pH is a preservative therefore I treat as primary. TA is a flavor issue (depth of acid notes) so it can vary.
* a FYI, potassium has a bitter flavor, I would minimize future use of it to maybe 0.1 pH unit.
 
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