Tables for Addition of Tartaric Acid
Household Measurements
Since California grapes can be low in acid content at harvest, measurement and addition of acid to musts or wine have become common among many home winemakers. Acid measurements are usually expressed as grams of acid per 100 ml of must or wine and in the USA it is expressed in terms of tartaric acid. To use the following tables, let’s suppose that we measured acid content and found that our wine contained 0.6 g/100 ml. We want to raise this value to 0.7 so we need to add 0.1 g/100 ml. The wine is in a strange looking 26 gallon barrel so how much tartaric acid do I need to add? In the table, I look at the column for my target addition of 0.1 g/100 ml and scroll down to the 26 gallon size of the container (I’ve put in the most frequently used sizes, it just so happens that we have 26 gallon French barrels). I note that I will need to add 3.5 ounces in household measurements or 98.8 grams in metric equivalents of tartaric acid. I will dissolve this in as small amount of water as possible and then add it to the wine.
| Tartaric Acid Additions Ounces of Tartaric Acid for Additions of: | |||||
| Gallons of Wine | 0.1 g/100 ml | 0.2 g/100 ml | 0.3 g/100 ml | 0.4 g/100 ml | 0.5 g/100 ml |
|---|---|---|---|---|---|
| 1.0 | 0.14 | 0.3 | 0.4 | 0.6 | 0.7 |
| 2.0 | 0.3 | 0.6 | 0.8 | 1.1 | 1.4 |
| 3.0 | 0.4 | 0.8 | 1.2 | 1.6 | 2.0 |
| 5.0 | 0.7 | 1.4 | 2.0 | 2.7 | 3.4 |
| 6.5 | 0.9 | 1.8 | 2.6 | 3.5 | 4.4 |
| 13.2 | 1.8 | 3.6 | 5.4 | 7.2 | 9.0 |
| 15.5 | 1.4 | 4.2 | 6.3 | 8.4 | 10.5 |
| 26.0 | 3.5 | 7.0 | 10.6 | 14.1 | 17.6 |
| 30.0 | 4.1 | 8.1 | 12.2 | 16.3 | 20.4 |
| 55.0 | 7.5 | 14.9 | 22.4 | 29.9 | 37.3 |
Metric Equivalents
Since California grapes can be low in acid content at harvest, measurement and addition of acid to musts or wine have become common among many home winemakers. Acid measurements are usually expressed as grams of acid per 100 ml of must or wine and in the USA it is expressed in terms of tartaric acid. To use the following tables, let’s suppose that we measured acid content and found that our wine contained 0.6 g/100 ml. We want to raise this value to 0.7 so we need to add 0.1 g/100 ml. The wine is in a strange looking 26 gallon barrel so how much tartaric acid do I need to add? In the table, I look at the column for my target addition of 0.1 g/100 ml and scroll down to the 26 gallon size of the container (I’ve put in the most frequently used sizes, it just so happens that we have 26 gallon French barrels). I note that I will need to add 3.5 ounces in household measurements or 98.8 grams in metric equivalents of tartaric acid. I will dissolve this in as small amount of water as possible and then add it to the wine.
| Tartaric Acid Additions Grams of Tartaric Acid for Additions of: | |||||
| Gallons of Wine | 0.1 g/100 ml | 0.2 g/100 ml | 0.3 g/100 ml | 0.4 g/100 ml | 0.5 g/100 ml |
|---|---|---|---|---|---|
| 1.0 | 3.8 | 7.7 | 11.4 | 15.5 | 19.0 |
| 2.0 | 7.7 | 15.4 | 23.1 | 30.8 | 38.5 |
| 3.0 | 11.4 | 22.8 | 34.2 | 45.6 | 57.0 |
| 5.0 | 19.0 | 38.5 | 57.0 | 76.0 | 95.0 |
| 6.5 | 24.7 | 49.4 | 74.1 | 98.8 | 123.5 |
| 13.2 | 50.2 | 100.4 | 150.5 | 200.6 | 250.8 |
| 15.5 | 58.9 | 117.8 | 176.7 | 235.6 | 294.5 |
| 26.0 | 98.8 | 197.6 | 296.4 | 395.2 | 494.0 |
| 30.0 | 114.0 | 228.0 | 342.0 | 456.0 | 570.0 |
| 55.0 | 209.0 | 418.0 | 627.0 | 836.0 | 1045.0 |
Please note that the above calculations were based on 3.8g/gallon=0.1g/100 ml increase.
For the scientist types some notes on L Tartaric acid:
- mw = 150.09 g
- pH of 0.1N = 2.2
- 1 g dissolves in 0.75 ml H2O at room temperature or 0.5 ml boiling
- 1g dissolves in 3 ml ethanol
- maximum solubility @ 10 C = 126g/100ml; @ 20 C=139 g; @ 30 C=156 g
- pKa1 = 2.93; pKa2 = 4.23 @ 25 C
