Understanding wine terms: What is acidity?
One of the most common questions we hear from our students in Oslo Wine School is “Why do we comment on acidity and why is it important in wines”. So here our wine expert Jane Nisbet Huseby will explain the concept of acidity.
How does acidity feel in a wine?
Acidity in wine gives you that lovely refreshing mouthfeel, that sensation that makes your mouth water and makes you want to have another sip. It´s an essential component in wine and ensure that wines also work well with food pairing.
Where does the acid come from?
Grapes contain two main acids, tartaric acid which is a strong acid present in many citrus fruits, and malic acid which is much weaker and commonly found in apples. These two acids develop in the grapes during the growing season and are carried over into the finished wine. Sometimes the malic acid is converted into softer lactic acid during winemaking for example often in Chardonnay to create more buttery tones.
How do I know how much acidity is in a wine?
Wine experts use a scale to measure acidity in a wine from including low, medium and high acidity. Grape varieties naturally have varying levels of acidity. For example, Riesling, Chenin Blanc and Sauvignon Blanc always have a high acidity, whilst varieties such as Pinot Gris and Muscat Blanc have naturally quite a low acidity. A wine which is very mouth-watering will be classified as having a high acidity, whilst a wine with a soft almost flat mouthfeel and very little mouth-watering effect has a low acidity.
Why do wine experts asses a wine´s acidity?
The level of acidity in a wine is a key component for assessing a wine´s quality and its ability to age. However, this is also used in context with the concentration and complexity of the fruit on the palate and the length of the finish of the wine. For example, despite its high acidity, a simple Riesling that costs perhaps 120 kr will not have the same aging capacity as a high-quality Riesling that costs more than 500 kr. such as a from a VDP Riesling producer.
Acidity is also key for retaining freshness and assisting ageability in sweet wines such as Coteaux du Layon, Trockenbeerenauslese, Tokaji Aszú and Sauternes. However, it´s worth noting that some wines can age beautifully despite having a low to moderate acidity, for example high-quality wines made from Pinot Gris and Gewurztraminer from Alsace.
