Acidity – What is It & How Important is it in Wine?

The acidity of a wine is one of its most appealing characteristics, enhancing its refreshing, crisp qualities as well as enabling wines to be paired with foods so successfully. It complements foods in a palate-cleansing, refreshing manner.

Acidity is usually tasted as soon as it comes into contact with the sides of your tongue. The taste sensation of acidity can be described as a ‘tart’, ‘sour’, ‘lemony’, ‘hard’, ‘crisp’, ‘bright’, ‘fresh’ and sometimes ‘minerally’.  When you think of acidity, it probably also conjures up images of lemons! One of the easiest ways to think about acidity is to imagine drinking a glass of lemonade, made from freshly squeezed lemon juice. That pucker, and the lingering impression of crispness and refreshment is due to the higher amounts of acid in the drink.

With wine, when you take that first sip, you may find the wine is refreshing yet slightly tart, and the word “crisp” quickly comes to mind. So if you love this sensation then what you’re enjoying is a wine with an obvious or higher acidity.

There are 2 different types of acid in wine, tartaric acid and malic acid. The main acid present in grapes is tartaric acid. The main type of acid present in lemons is citric acid, which does actually taste lemony! Malic acid is the main acid found in apples, and interestingly, the best types of apples to cook with, are those with high acidity levels!

In grapes and wine, as well as tartaric acid, there are smaller amounts of malic acid, and citric acid naturally present. When a wine goes through malic lactic fermentation, then the amount of malic acid decreases in the wine, and the amount of lactic acid increases, as the malo lactic bacteria metabolise the malic acid producing lactic acid. The end result of this acid conversion, is that the wine is less acidic when tasted, and has a smoother, softer mouthfeel.

In general, white wines have a higher acid level than red wines. Acidity gives wine its crispness on the palate. A dry wine, both a white and a red wine, needs good levels of acid to provide liveliness and balance; sweet wine needs acidity so it does not seem cloying. Too much acidity will make the wine seem harsh or bitter; too little and the wine will seem flabby and dull.

There are time during the winemaking process when we may need to add more tartaric acid to a wine to make it better balanced, especially if it’s been a hot growing season as the acid level in the ripe grapes is then much lower. The tartaric acid that we buy from our suppliers has been reclaimed from the winemaking process, which is pretty cool! It is a natural product, reclaimed, re-used and recycled through the winemaking cycle again.

An important point to remember is that your perception of acidity, as with other flavour components in wine, should not be considered independently. Sweetness and acidity, for example, balance each other. A wine high in acidity that also has a bit of sweetness will seem less acidic. Tannin and acidity, on the other hand, seem to reinforce each other. A big, tannic red that is also high in acidity will seem even more tannic and/or acidic.