Understanding Acidity in Wine
What is acidity in wine and how does one taste it? Also, how acidic is wine? And why is acidity important? Answers to these questions and a few more will help you understand this core wine trait.
Knowing about acidity will help define what you like as well as understand the role of acidity when pairing wine and food.
Understanding acidity in wine
Acids are one of 4 fundamental traits in wine (the others are tannin, alcohol, and sweetness). Acidity gives a wine its tart and sour taste. Fundamentally speaking, all wines lie on the acidic side of the pH spectrum, and most range from 2.5 to about 4.5 pH (7 is neutral).
There are several different types of acids found in wine, which will affect how acidic a wine tastes. The most prevalent acids found in wine are tartaric acid, malic acid, and citric acid.
How to taste acidity in wine
Sit for a minute and imagine yourself tasting lemonade and pay attention to how your mouth puckers just from thinking about it. This sensation is how our mouths anticipate the acidity in lemonade. The next time you taste wine, pay attention to this specific puckering sensation.
After tasting several wines, you’ll create a mental benchmark of where the acidity hits your palate and you’ll also begin to notice that some wines (such as Riesling) tend to have higher acidity than others.
TIP: pH is a logarithmic scale, so theoretically, a wine with a pH of 3 is ten times more acidic than a wine with a pH of 4.
Sweetness decreases the sensation of acidity
The perfect way to contextualize how sweetness reduces the sensation of acidity in wine is to compare how you react to tasting a raw lemon to Coca-Cola.
Technically, they have the same pH (around 2.5), but since coke is sweet, it’s not as intense. This is why Brut sparkling wines taste dry but only have a few grams per liter of residual sugar.
Balancing acidity in food and wine pairing
When pairing food and wine, it’s useful to first take into account the tastes found in a dish (sweet, sour, bitter, salty, fat, umami, etc.) Your goal is to create a basic profile of the dish in your mind and then select a wine that complements those fundamental traits.
When working with acidity, you’ll notice that sweetness, saltiness, and fat balance the sour taste of acidity. This is why Champagne and French fries pair so well together (acidity + fat and salt).
Acidity in wine is important
As much as modern health has demonized acidic foods, acidity is an essential trait in wine that’s necessary for quality.
Great wines are in balance with their 4 fundamental traits (acidity, tannin, alcohol, and sweetness) and as wines age, the acidity acts as a buffer to preserve the wine longer.
For example, Sauternes, a wine with both high acidity and sweetness, is known to age several decades.
How climate plays into acidity in wine
Acidity is a perfect example of one of the fundamental taste traits that are affected by different climates (warm vs. cool).
When wine grapes are still green, they have very high acidity. As they ripen, the acidity tapers down, and the sweetness increases.
The perfect moment, of course, is when the grape is perfectly sweet, ripe, and still possessing enough acidity to make great wine. This is where climate comes in. A region that produces wines with naturally higher acidity will have either cooler nighttime temperatures or a shorter growing season.
The cool nights and cold weather stops the grapes from losing their acidity. In a region with a shorter growing season, there’s also the possibility that the grapes never quite get ripe enough, which results in both more tart and more herbaceous tasting wines.
Acidity in wine is complex
The topic of acidity in wine can go quite deep. For example, the type of acid present in a wine can also affect our perception of sourness. A great example of this is the difference between unoaked vs. oaked Chardonnay.
Often, during the aging process, a wine’s malic acid is converted to lactic acid (in a process called Malolactic Fermentation), which results in a smoother, less tart-tasting wine.
Another facet of wine that can be confusing is a wine’s total acidity. This is something that’s often noted on a wine tech sheet.
Total acidity tells us the concentration of acids present in wine, whereas the pH level tells us how intense those acids taste. For example, if you have a wine with 6 g/l total acidity and a pH of 3.2 it will taste more acidic than a wine with 4 g/l total acidity with the same pH level.
Image credits: Elle Hughes