Acid addition......

I calculated it using "WineCalc" I downloaded from this web site

It is a good program and from my calculations I got 16.7 gram of tartaric acid, 158 grams of Tataric acid seems quite high.

Walter

....then that would be about 3 tsp. for 11US gallons. That seems very low.

....actually , your decimal point needs to be moved to the right by one ....167.2 grams according to this page

I can't use the wine calculator as I'm a mac user.

andyjone - My first question would be what kind of grapes are these and do you really want the starting TA to be 0.70%. If you're sure you want to raise acid this much here's what I think will be required.

You have 11 gallons of crushed grapes. I believe this will contain about

7.4 gallons of juice which is the same as 28009 ml. At 0.3%TA the juice contains 84grams acid. At 0.7%TA the juice will contain 196grams acid. So, you will have to add 112grams acid. But, if these were my grapes I would add portions of the acid, each dissolved in water, and stir the must like crazy. I would have my pH meter in the must as I did this and would be very careful not to let pH drop too low. Do these additions slow taking time between additions so you can be sure to don't let pH drop too low.

Finally, I would have done the acid additions before adding anything to the grapes, especially the yeast.

Bill Frazier Olathe, Kansas USA

NaOH solution won't last that long. Either get new NaOH (easy way) or titrate your NaOH solution against HCl to determine its actual concentration.

Thanks for the advice Bill. I'm always prone to at least one mistake during the whole procedure. First though I think your estimation of the amount of juice in the must might be low. These are CV grapes, a primary blend of Zin,Cab. Sauv., and Sangiovese....4 lugs worth in all. A lug generally gives me 10 750ml bottles of finished wine, with a loss of 10-15% during the process. This would be about 8.75 US gallons. However, the acid level seems off to me. I think I will get new solutions and retest before I add anything at all. One disadvantage is my lack of a PH meter but thats another story. And if additions are to be made they will surely be made in steps and slowly.

William Frazier wrote:

Those grapes are jucier than I grow here in Kansas. My standard estimate for juice is 2/3 the volume of must after stems have been removed. It's just a figure I use and it's sometimes low or high.

Bill Frazier Olathe, Kansas USA

I appreciate the input from this group. I'm going to get a fresh acid kit as I said and will post the results. Winemaking is very much a learn as you go experience is it not? On a personal front.... I do not know any wine makers beside myself. My only advisors are in cyberland , so I do a cherish your input.....andy j.

William Frazier wrote:

William,

What do you consider too low for a starting Ph and why??

Bob

William Frazier wrote:

Hi ..tested with fresh acid kit this morning ....results the same. TA

0.30%. Added 120grams of tartaric acid in 3 steps , checking acid each tiime til I achieved 0.60%TA. I am attempting to get PH measured properly at the chemistry dept. at the local university.

Just a note for future reference - if the sodium hydroxide were too old and started losing power, your measurments would be _higher_ than the real number and not lower. It's because the solution is weaker, and so you'd need more of it to get to thecolour change point.

That said, I've got burned before by relying on the TA measurements to adjust acid, so if you're getting strange numbers, either do a pH check or use your tastebuds for a sanity check. Numbers do lie occasionally.

Pp

I like the taste buds method for TA adjustment.

Another way to check your NaOH is to make a 'standard' solution of tartaric acid. If you really think you have 0.3% TA, double check by dissolving 0.3 gms Tartaric acid in 100 gms of water (100 ml) and titrate that with your TA test kit.

I like to limit my 'per add' tartaric additions to 3.6 gms per gallon. You can always add more the next day if you are still low. You can't take it out except by cold stabilizing it to precipitate potassium bitartrate. The only time I would add tartaric acid to 0.7% TA in a red wine is when the must has too high a pH (>3.7) and I'm using the Tartaric Acid to shift the pH downward.

BTW, ripe (>25 degBrix)CV grapes often have TA in the 0.3-0.4% TA range. The hot nights and days drop the acid pretty quickly as ripeness approaches.

Gene

pp wrote:

At this point in the game, with all the sugar etc, I can't be sure of anything taste wise. I adjusted to 0.60TA , then ran a sample over to ene Chemical Engineering Dept. at UNB and got a PH meter put in it. It reads 3.51. So....3.6 TA and a PH reading of 3.51. How does that sound?

That sounds about as good as it gets!!! Congratulations Gene

Andyj didn't respond saying what grapes he has. But, if these are red grapes I would not like to see the pH below 3.3. If the pH is lower, and if malo lactic fermentation is desired in a red wine, it may be difficult at a lower pH. Malo lactic fermentation will increase pH by about 2.5 pH units. A wine starting fermentation at 3.3 will have a pH of about 3.5 after malo lactic fermentation. Then, when you cold stabilize the wine the pH will not drift much lower or higher. If pH is much below 3.4 or above 3.6 before cold conditioning pH may drift up or down and end up where you don't want it.

If Andyj's grapes were white grapes I would like to see the pH no lower than

3.3 for the same reasons and I wouldn't be concerned if they were 3.4 assuming no malo lactic fermentation was planned.

Bill Frazier Olathe, Kansas USA

Bill ...as I stated earlier in an earlier post in this thread, the grapes are a blend of Zin, Cab Sauv. and Sangiovese. Also I'll try to avoid a MF as my PH is at 3.51 right now and not interested in it going to 3.7.

Hi Andyjone, You sound good to go at this point, but I still don't get that initial acid value. I get about the same yield as you; I guess at around 2.2 to 2.5 gallons (US) per 36 # lug.

I make wine from CV grapes and never saw it below 0.4% initially but rarely see it higher than 0.5% either. TA can increase after fermentation and usually does with CV grapes; I usually shoot for not more than 0.55% TA initially because I don't like tartness in a finished dry red and anything over 0.6% usually tastes tart to me. You have good number now, I would let things be and if necessary cold stabilize out a little acid. I never do ML on CV grapes either because I just don't see it helping, the pH is usually marginal and the TA is not too high to begin with.

I do as Bill said too, I calculate what I need and add half and retest. Joe

snipped-for-privacy@gmail.com wrote:

I know Andy...after I posted I looked back at your post and saw you were working with red grapes. I have malo lactic bugs floating around in my basement winery. So, it's pretty hard for me to avoid ML fermentation whether I innoculate or not. I do add ML culture to my red wines and Chardonnay but some whites I like sans ML fermentatiion. Lysozyme stops it in it's tracks if you have any fear you can't avoid it otherwise. Your blend sounds delicious and the pH is very good, although I wouldn't worry about pH 3.7 in a red wine.

I know what you mean Joe. It seemed unusually low to me. I did however test a total of 6 times using 2 different kits. Then 4 more tests as I added the acid in steps. I wonder if anyone else is seeing low TA numbers from the CV this fall?