Acid taste

[cuz]

I have tried two digital PH testers to no avail. I can not get an accurate reading and from what I see in reviews online the consensus is they are not dependable. That being said my wine just taste like there is too much acid. Gives me acid indigestion and my daughter says it taste a little metallic on the back end. Too late for Malo fermentation but can I add malic acid to soften the taste? I am hesitant to raise the PH for fear of spoilage. I did try Tanin Riche Extra

 

[Ajmassa]

Not too late for MLF unless it’s in the bottle. Let the so2 drop down nice and low and you could pitch. Springtime is perfect. Cold stabilizing outside now in the winter would drop out some acid too.
You could get an accurate TA reading without ph. That would help narrowing it down. Definitely should get some numbers before deciding anything. I once sent samples in to a local lab when I had some suspect numbers. Keystonehomebrew.com and just check off what items you want tested

 

[Scooter68]

?? If you calibrate them virtually any digital pH tester will get you close enough for wine making. (Unless it won't calibrate at all.} The key is to calibrate them. Even the high dollar units have to be calibrated and just as often as the low-end models. As for a consensus of not reading...I've seen a lot of folks who have no clue about the proper use of simple instruments. So when I read the complaints... I am a bit skeptical unless I see a serious trend on a product. Electronic pH meters have been around a long time and unless yours fails a simple test like I suggest below, I'd trust a meter a lot quicker than a TA test which is pretty tough to read on red or dark color wines.
If you are having doubts about the results, try this:
1) Rinse the meter with distilled water and let it set in that water for 5 minutes.
2) Calibrate with both the 4.00 solution and the 7.01 solutions
3) Rinse the meter with distilled water again
4) Test your wine, Let it set in the wine for at least a minute and settle.
5) Rinse the meter with distilled water again
6) Check calibration again. Start with the 4.00 buffer solution first.
Unless the meter has wandered of during that short period of time, there's no reason to worry. Variances of .05 or less are not that significant to basic home wine making. Re-calibration is recommended frequently but in my personal experiences if I am using the meter several times in a week, I haven't found any discrepancies or wandering in the readings. Just be sure to keep the bulb wet - follow the directions. If you don't use it for a couple of weeks - recheck it before using. Again even the meters sold for $200.00 + have to be re-calibrated often.

There are other things beside acidity that can leave strange tastes in the mouth like you describe.One that comes to mind is zinc tablets (Now a common OTC item taken during cold and flu season.) Here's an article exactly about causes of what you describe: https://www.ehealthme.com/ds/alcohol/metallic-taste/

 

[Stressbaby]

I agree, get some numbers. And tell us what kind of wine it is.
But keep in mind pH and TA are different things. If the problem is acidic taste, your concern should be the TA more than the pH. I have a pair of whites right now in carboys, they taste roughly the same acidity, the TAs are 9 and 10, but the pHs are 3.4 and 2.7.
Malic acid is not going to soften the taste. You might consider KHCO3, K2CO3, or CaCO3, but again it is really hard to know whether those are options without both TA and pH numbers. And of course the answer could be as simple as a little back-sweetening.

 

[cuz]

OK thank you - I'm going to try to calculate my ph meter again and add Sodium Hydroxide to sample until I reach 8.2. If it works I don't understand the math and cc units. For example, if I add three drops of Sodium Hydroxide to get to 8.2 how much calcium carbonate do I need to add. Oh Stressbaby I am making a Carmenere.

 

[Scooter68]

Best bet is to look at your container of Sodium Hydroxide and find out the concentration of it. Then look up the process for testing with a pH meter and calculating the results. Using a pH meter with the TA test is easy once you learn the process and calculations.

Also be aware that the change in readings happens fast once you get close to 8.2. So go slow and stir the sample well after each addition of NAOH

Just don't forget to toss out that sample after testing.

 

[Ajmassa]

Forget figuring how much calcium carbonate just yet. First get some legit levels.
Stopping at 8.2 with a meter or by color change doesn’t change the process. You’ll likely have .1N or .2N sodium hydroxide.
If .2N you want to use a 15mL sample. And adding sodium hydroxide until 8.2 or color change. 1:1 ratio. 6mL used means .60g/L TA (or 60%)
If .1N you want to use a 5mL sample (diluted with ~10mL distilled water makes test easier and doesn’t effect the numbers). And add sodium hydroxide until 8.2 or color change. Then multiply amount used by 1.5. If 4mL used then 1.5 x 4mL= .60g/L.

 

[cuz]

Stressbaby mentioned backsweetening. What do you folks use to do this. A local wine juice vendor told me to be sure to use fructose and not table sugar (sucrose). Has anyone tried other additives to backsweeten?

 

[Stressbaby]

I just use plain table sugar, it's fine.
But if it is Carmenere maybe you want to solve the acid problem some other way and keep it dry...

 

[Scooter68]

Agree completely with stressbaby. There are lot of opinions about back-sweetening out there but - Never heard that using table sugar was a bad thing. Sometimes.... folks want to sell you something. If you are just getting started - keep it simple for now. Plain table sugar works fine. You can make a simple syrup using 2 parts sugar to 1 part HOT water. OR You can put it in without dissolving and stir, stir, stir. It's up to you. For back sweetening 'bench trials it's a lot easier to work with a syrup. I've started using plastic syringes and working in ml of syrup since thats a finer measurement than 1/4 tsp from a measuring glass or spoon. Got my syringes free from a Walmart prescription counter and it makes it nice and easy to measure and dispense into my 8oz cup of wine.

BUT first get your acid issue under control. THEN move on to back sweetening. Keep in mind that back-sweetening will take a little bit of the edge off the acidity.

 

[sour_grapes]

@cuz , take a looky here: https://www.winemakingtalk.com/threads/mixing-the-sugar-for-backsweetening.64739/#post-679946

 

[Arne]

If you sweeten it, make sure you stabalize it if you use table sugar. K-meta and pot. sorbate added to it should keep it from refermenting on the sugar. Arne.