Re: The High pH and High TA Problem

Tis a personal judgement call at this point, Michael.

At crush, it would be hands down: add enought tartaric to achieve a 3.4 pH. Then the wine will take care of itself through both fermentations and cold stabilization (or aging).

Some things that aren't clear from your post:

Are the parameters you list present ones, or from crush?

Has MLF occured or do you plan on doing one?

Adding enough acid now to bring the pH within reason may produce an undesirable effect on the taste of the wine: ie, too tart.

If the fermentation was clean, and your cellar is clean, then bottling a high pH wine is feasible, though still risky. Chances are that it won't last very long, but there are other factors that come into play (tannins comes to mind). Part of the problem is that SO2 is virtually uneffective at that pH level. Depending on the volume, I might consider just throwing a party! In other words, drink up soon (within the next 8 months to a year).

clyde

Trying to figure out how to drop the temperature that much. Also, does it matter when (e.g., right before bottling or will anytime work)? For instance, ambient temperature will be about mid-50's in the winter. I could transfer the barrel contents to a stainless tank and blast it with dry ice and get the temperature down. But I don't know about getting it to 20F. Won't it, uh, freeze?

BTW, how much TA would fall out? If I acidified to 3.6 right , that would put my TA at about 1.0 or so. Will 0.3 or more TA fall out?

Michael, Can you put it outside, but covered so as not to expose it to the sun? That would get it pretty cold here in Pgh, PA. Several days, not hours, is what I would plan for.

I would add .1 and see where the pH went, it may turn right around, it will drop faster as the potassium comes out of the wine, so you do not have to add too much.

it freezes at 5 F. The colder it gets, the faster it drops out, you can add cream of Tartar to speed this up too.

I can look it up for you later when I get home. Regards, Joe

Since this is an entire barrel, maybe your best bet would be to pullout several bottles worth adding tartaric to each in various amounts. (And top up.) The reason to add tartaric only is two fold,it reduces pH more that malic or citric, and the excess is coming out if chilled. When it does, it pulls potassium out too, further reducing pH.

Your wine probably has very little tartaric acid, or is high in potassium as a guess. I would think the later makes more sense. Potassium Bitartrate forms when you chill wine, this reduces potassium and tartaric acid. The colder, the less it can hold.

Personally, I might do this. I would pull a sample, add tartaric only to a TA of 8g/l and remeasure pH. That would go in the refrigerator for a few weeks. Then I would remeasure. Adding potassium bitartrate allows you to pull this out at higher temps, you can add a few grams to another sample to see if that works better. You want to get under

5C if possible, any fridge will do 6 C. Wine at 5 degrees C can hold 1/3 of the potassium bitartrate it can hold at 30 C, so you can still pull a bunch out even at fridge temps. You will see a crust of crystals form, you rack off of that while still cold.

Others may have better advice. This seems least risky, and you can predict how much to add and what will probably happen this way. You can do this anytime.

Regards, Joe

Why would my TA register > 0.71 if there was little tartaric acid? Are you saying that it's all citric/malic? Also, how do I find out the potassium levels? I don't know of any test for that.

I will definitely experiment with some small batches to see what the impact of acid additions makes.

So the reality is that we have four barrels of syrah (I'm only doing one, but my partners have three more), so this is a fairly large amount of work. I do have an extra fridge and a 100 liter stainless thank that will probably fit in... so it may not be too bad. Approximately how long does it need to chill before the crust forms?

Thanks for the advice!

The parameters I gave are current from the lab. Primary is just about complete (< 1 brix). I do plan on MLF.

The fermentation was clean, the cellar is clean. As I mentioned in a previous post, we actually have 4 barrels of this stuff, so it'd have to be a really, really big party.

I figure I've got a bit of time before I panic and am just trying to understand my options.

I doubt that is the case, I think it's potassium. As the grape berry matures, malic decreases and tartaric increases. If your grapes were ripe, I doubt that it is low tartaric.

Testing for high potassium is probably not worth the cost, but high is considered above 1 g/l. You would do the same thing, regardless. See if your local library can get its hands on 'Wine Analysis and Production' by Zoecklein, et al. You may want to read chapter 4 'Hydrogen Ion (pH) and Fixed Acids' and Ch 15,'Tartrates and Instabilities'.

In short, it tells you to get the sample below 3.65 pH, chill to 32 F, seed with 4 g/l of potassium bitartate and stir like crazy. This should pull out excess tartaric, (which you added) and potassium, (which is probably your problem). I way oversimplified this, that's why I suggested the book. If it does not work out, you only wasted one bottle... Most of the reaction occurs in 90 minutes according to the book, but I would give it two weeks, you have time and are not cold enough in a regular fridge.

Hope that helps, Joe

BTW, where can I find the appropriate ranges for Potassium?

I Googled this

to help derive an estimate of potassium, but don't know what good/bad levels are.

...Michael

OK, here's the current tentative plan. I'm going to acidify either to pH of 3.6 or TA of 0.9... whichever comes first. The question is how to precipitate the tartrates.

My understanding is that some will come out during the winter (average

55F degrees in cellar). Perhaps during the colder part of the winter (32-40F), I'll rack the barrel into carbuoys and just leave them outside for two weeks. Worst case, come next Summer, I'll figure out some way to refrigerate it.

Thoughts?

Assuming I acidify, the syrah hasn't quite fermented - it's now at about 1.5 brix. Any suggestion whether I should acidify before fermentation is complete or will this throw off the fermentation?

I would do it now, but measure the pH again first... Don't forget to degas the sample. Regards, Joe

Yes, degas always. I don't think I can predict precipitation. Only tartaric precipitates, I don't know how much you have now. If you are going to the Wine lab, you may want to ask them what to do, they are VERY good from what I hear. I commented on you pH meter in another post. Regards Joe