Question from Amanda: Where and what acids are found in wine. Which wines have more acid (dry or sweet) and why due to the climate. Explain why and how titration can be used to determine the relative acid content of wine. If you could help answer my question i would be very grateful.
Answer: Hi, Amanda! Thanks for your question! I’ll do my best….
The main grape acid is tartaric, a relatively strong acid, unlike most fruits. It’s followed by malic (found in lots of fruits and vegetables) and there are trace amounts of lots of different acids. We have an article on wine components, including acid, at goosecross.com.
Generally, white wines are higher in acid than reds, for aesthetic reasons. Sweet wines should be the highest of all, to offset the sweetness, or the wine will be cloying.
Cool climates usually produce wines of high acid compared to warm climates because heat causes the sugar to go up and the acid to go down. A Chardonnay from Burgundy, France is almost always higher in acid than a Napa Valley Chardonnay because of the difference in climate. Imagine trying to ripen tomatoes in a cold climate–they will be quite tart!
Titration is a simple color-change test. I’ve paraphrased this from a wine text: Titration is the process of determining the concentration of a substance, such as acid, in a solution by adding a carefully measured standard reagent (usually sodium hydroxide) until a reaction (change in color) occurs due to the presence of an indicator (phenolphthalein). Most home winemakers buy inexpensive kits to do this.
I hope this helps you. Are you studying wine making?