[Fritz]

would 3 cc's of sodium hydroxide diluted in 6 gallons of wine be unsafe to drink?  i accidently spilled this amount in a wine making hit why testing for acid levels.  I need to know if I should dumpt the batch out.

[jdurg]

The answer to that is yes and no.  Since you didn't include the concentration of the NaOH solution, I don't know how much NaOH is in there.  If it was 3 mL of 18 molar NaOH, then there may be a small problem.  If it's 3 mL of 0.000018 molar NaOH, then there's not problem at all.  The only thing I would do is test the pH of the wine.  Wine should be slightly acidic.  If the pH is greater than 7, then I'd suggest dumping it because it would wind up having a very bitter taste.  (The sodium and hydroxide ions pose no toxicity threats.  The hydroxide ions will probably end up being neutralized anyway).

So check the pH.  If it's high, dump it.

[Fritz]

jdurg--
Thank you for the quick and informative response.  The bottle of Sodium Hydroxide with the test kit says it ia 1/5N or 1/5 Normal.  Does that give you any more information to draw a conclusion?

[mike]

Here is an msds for NaOH solution (1M I think). You can check out the LD50 etc.

I think as jdurg said that it would probably only affect the taste if anything, but more than likely it has been neutralized, maybe test the pH again?

[mike]

NaOH msds

[jdurg]

Okay, that's important knowing the concentration.  For an NaOH solution, Normality is equal to Molarity, so your solution has a concentration of 0.2 Molar.  One Liter of solution will have 0.2 moles of NaOH in there.  Therefore, 3 mL of solution will have 0.0006 moles of NaOH.  6 gallons is equal to about 22.7 liters, so your OH- concentration would be 2.64x10^-5 molar.  (That's very dilute).  If there was absolutely no acidity in the wine (I.E. if it were just distilled water), your pH would now be about 9.4 which is fairly basic.  However, wine is quite acidic with a typical pH being about 4.0.  So if we assume that your wine is a typical wine, then the hydrogen ion concentration would be 10^-4.  So what we know is that in the 22.7 liters of wine we have 22.7x(10^-4) or 0.00227 moles of H+.  OH- will neutralize that H+, so the 0.0006 moles of NaOH you put in there will neutralize the same amount of H+ ions.  Your wine will now have 0.00227-0.0006=0.00167 moles of H+.

So now we can figure out the pH of your wine.  0.00167 moles of H+ in 22.7 liters (We're ignoring the paltry 3mL that was added by the volume of NaOH) is equal to a [H+] of 9.74x10^-4 Molar.  This means that your pH is now 4.133.  You'll never notice that change.  So your wine is perfectly safe to drink.

[Borek]

jdurg - you calculation COULD be right, if the acids in wine were strong ones. But they are weak, so there will be buffering effect and the result will be that pH change will be even smaller.

And the wine is perfectly safe to drink.

[Fritz]

you guys kick some serious A55.  Now if I can only get the proper amount of malolactic fermentation to take place...I'll have an even fruity tasting wine that has a lightmoutfeel.

Thanks all.

[jdurg]

jdurg - you calculation COULD be right, if the acids in wine were strong ones. But they are weak, so there will be buffering effect and the result will be that pH change will be even smaller.

And the wine is perfectly safe to drink.

Very true, but I had to make a ton of assumptions anyway as I don't know the exact pH of the wine.  I just had to use the general belief that wines have a pH from 3.3-4.0 on average.