Titrations for total acid


Burette- 50 ml
Retort Stand
3 250 ml flasks or clear plastic cups
45ml grape juice
250ml  .2M  NaOH=   2gms of  NaOH to 250ml distilled water






  1. Measure 15 ml of juice into each of 3 flasks or cups
  2. Dilute to 150ml with distilled water
  3. Add 7 drops phenolphthalein to each flask
  4. Add 50ml of NaOH solution to burette
  5. Titrate into juice until colour change is reached (end point)
  6. Calculate %TA .
  7. e.g   9ml  = 9gms acid/100litre TA

Desirable level
White wine 7-9
Red Wine 6- 8



Make sure you read the burette at the low point of the meniscus.

The reading here is 4.8ml







A pH metre can be used instead if you wish as long as you are confident your meter is accurate.

The pH at which phenolphthalein changes colour is 8.2

Therefore adding 5ml quantities of NaOH (sodium hydroxide) and checking the pH change with a meter until the meter is stable at pH 8.2-8.4

CAUTION: This is very difficult to achieve with a hand held meter. They are not sensitive enough to small changes and tend to react suddenly to a gradual build-up of NaOH.

The amount of NaOH you have added to the wine sample is equivalent to the Total Acid of your wine.





This page was last updated on 10/01/2011