Photo by Christine Isakzhanova on Unsplash
We know that wine is a lovely drink made from fermented fruit, but what exactly is in a bottle of wine?
Water
Wine is usually comprised of 80-90% water that is directly extracted from squeezed grapes. In rare instances, water may be added to dilute the wine when the alcohol content (or potential alcohol) and/or phenolics become excessive. However, this practice is quite uncommon.
Alcohol
Between 10% and 15% of wine consists of alcohol, specifically ethyl alcohol (also known as ethanol), which is the primary alcohol component in wine. Other alcohols, such as glycerol and methyl alcohol (also known as methanol), may also be present in wine. Why is alcohol significant in wine? It imparts a “body” and “weight” to the palate, providing a tactile sensation as the wine’s elements linger in the mouth. Ethanol plays a crucial role in your nose as well, as it evaporates rapidly and carries the wine’s aromas up to your olfactory receptors.
Acid
The amount of acid in wine typically ranges between 4 to 8 grams per liter (g/L). To put this in perspective, a bottle of wine is 750 ml or 3/4 of a liter. Thus, a typical bottle of wine has 3-6 gm of acid. This level can vary based on the style of wine, grape variety, and region of production.
Tartaric acid is the most common acid found in wine.
Sugar
Most wines, including common varieties like Cabernet Sauvignon, Chardonnay, and Merlot contain less than 4 g/L of residual sugar or less than 3 gm. Glucose and fructose are the two simple sugars that can be found in equal amounts in the grapes. At harvest, grapes typically contain about 15 – 28% sugar. These sugars are highly fermentable, and the yeast converts these sugars into ethanol, making grape juice into wine.
Phenolic Compounds
This gets a bit technical, so hang in there. Phenolic compounds are tiny molecules, called polyphenols and phenolics and they can really make a difference in wine. Some of these compounds include anthocyanins, flavanols, tannins, and vanilla. We know that vanilla aromas and flavors come from oak barrels and tannins come from the skin, stems, and seeds of the grapes. But, the other compounds affect the wine’s color. Anthocyanins are the ones that give red wine its color. The more anthocyanins there are and the less acidic the wine is, the redder it will be. Flavanols are yellow pigments found in white wines. These compounds are sensitive to light, which helps wine look more golden in warmer climates compared to cooler climates.
So, there you have it! Wine is primarily composed of water, along with some alcohol, acids, sugar, and phenolic compounds. When a wine tastes ‘off,’ it’s typically due to an imbalance in these components. Acquiring the right balance is challenging, which is what makes winemaking such a captivating art. Cheers!