Acidity Levels in Wine

Acidity in wine is one of the four fundamental traits of a good wine (Acidity, Tannin, Alcohol and Sweetness). For a wine to be considered “good,” each of these traits must be in proper proportion or ‘balance’ to each another. If there’s too much of one part, the wine will be off. And, if there’s not enough of a specific component, the wine will be lacking.

So, the acidity of a wine must play its own fine balancing act. While there are no magic “right” numbers for the level of acidity in a wine, there are generally accepted ideals. But, as usual, personal taste is still the simplest determining factor.

As a quick review, pH is a measure of acidity and is a logarithmic scale. So, a pH of 3 is ten times more acidic than a pH of 4 (the lower the pH the more acidic).

Wines lie on the acidic side of the pH spectrum, and most range from 3 to about 4.5 pH. This is compared with water, which is neutral, with a pH of 7 (not acidic), milk at a pH of 6.7, coffee at 4.5-5.0, and lemonade at 2.6 (very acidic).

Acid is important in wine because it acts biologically as a preservative. A red wine with a pH of 3.5 to 4 protects against most spoilage bacteria allowing it to age over years rather than months and allows it to develop deeper more complex flavors. In white wines there is generally stronger acidity with the pH being between 3.0 to 3.5.

In addition to the pH level of a wine, its “Titratable Acidity” or “Total Acidity” (TA) is another way of measuring acidity. And, this is a measure that usually appears on a wine’s Tech Sheet that is generally available on-line from the winery.

Most red wines will have a total acidity of about 0.6 to 0.7% TA that converts to 6 to 7 grams/Liter (g/L) – that is 6 to 7 grams of acid per liter of wine. A white wine will have a higher TA between 6.5 to 7.5 g/L

• Dry White Wines – 6.5 – 7.5g/L

• Sweet White Wine – 7 – 8.5g/L

• Dry Red Wine – 6 – 7g/L

• Sweet Red Wines – 6.5 – 8g/L

• Sherry – 5 – 6g/L

So, keep those taste buds perked up and see if you can detect an acidic wine (e.g., Sauvignon Blanc) over one that is not (e.g., Viognier), or a wine where the acidity is out of balance with its other components. Cheers!

Ever Wonder? Why is a Wine Said to be "Refreshing?"

There are a lot of terms that are thrown around regarding wines. And, one that you may hear about in the warmer months is “refreshing.” But, what exactly does it mean for a wine to be considered refreshing?

Well, in a word, it’s acidity.

Acid is a natural component in a grape. But a wine maker is looking for just the right balance between the grape’s acid level and its sweetness before harvesting the grapes. The sugar in a grape is what is converted to alcohol during fermentation and the acid is what gives the wine it balance, flavor and mouth-feel.

Have you ever noticed after sipping a lemonade that it can make your mouth tingle and give you a mouth- watering sensation? Well, it’s the acidity of the lemon that gives you that mouth-watering sensation. You may also experience a mouth-watering sensation when sipping your favorite cola drink. In both cases, acid is the primary factor in the sensation in your mouth or the “mouth feel.”

So, now that you know that it’s acid that causes a wine to be described as “refreshing,” what are some higher acid wines? In general, they are going to be the light-bodied white wines but rosés and sparkling wines can also be refreshing.

Here’s a brief listing of high-acid white wines:

• Sauvignon Blanc

• Pinot Gris (Pinot Grigio)

• Albariño

• Chenin Blanc

• Grüner Veltliner

• Riesling

• Vinho Verde

By no means is this an exhaustive listing of high-acid white wines, but these are the best-known ones.

So, acid is just one of the four fundamental traits in good wines. Next time we’ll take a quick look at the other three. Until then, Cheers!

Malolactic "Fermentation" of Wine - Not

The flavors in wine come from three things - the grapes, fermentation and aging. We've explored the flavors from the juice of the grape, the flavors from the grape skins, seeds and stems and we've seen that the yeast can affect flavors during fermentation. But, there's another process that affects a wine's flavor and it's often called Malolactic Fermentation.

But, getting right to the point, this is not a fermentation. It's actually a process in which one type of acid in the wine is converted to another type of acid. So, it is more correctly a Malolactic Conversion, not a fermentation.

In this conversion process, a tart acid that naturally forms in wine, malic acid, is converted to lactic acid. While the tart malic acid can yield flavor sensations much like a tart green apple, the lactic acid is much softer and creates a richer mouthfeel that is often called buttery and can make a wine seem velvety smooth.

Most red wines undergo malolactic conversion while only some white wines, notably Chardonnay, undergo malolactic conversion. This process is most often performed shortly after the end of primary fermentation and just prior to the aging process.

And, speaking of the aging process, we'll explore the flavors that are imparted to wines as they age in next week's blog. Until then, Cheers!