Winemaking adds truth to the saying that beauty is only skin deep.
Apples and oranges. You’ve heard the expression used to describe comparing two things that are extremely different. It’s easy to associate this cliché with the difference between red and white wine because there really is a huge difference.
But there are also a few striking similarities. One of them even has to do with what grapes and apples have in common. Now that we’ve created a veritable fruit salad of allegories, read on to discover the main differences between red and white wine—besides the color.
We’ll start here because it’s only fair to satisfy the question we just brought up about what grapes—both red and white—and apples have in common. Skin color.
For the most part, if you peel any variety of apple, you reveal the same color flesh. The apple’s skin can be green, red, or yellow.
Similarly, when removed from their skins, both red and white grapes create a clear liquid when juiced. That’s right: red grapes do not produce red wine. Well, actually, they do—but only if you include their skins. And, this brings us to one of the most striking differences between red and white wines—which is how they’re made.
Nobody peels grapes before they start the process of winemaking. Imagine the time and effort this would take! However, during the production of white wine, the skin is separated from the clear juice. And while making red wine, the skin and seeds—and sometimes the vines as well as even leaves—are included in the juice fermentation process.
It’s known as maceration, and this is what causes the clear grape juice to turn red. It’s also a bit like brewing a cup of tea. A longer seep produces a darker brew. Longer maceration periods produce darker red wines, also resulting in more intense flavors.
It turns out that the secret to a wine’s complex flavors and bold personality lies in the grape skin. Does it surprise you, then, to discover that Cabernet Sauvignon grape skins are among the thickest to be found?
Wood vs metal
Fermenting with or without the skin might be the main difference between what makes a red or white wine, but what the juice from the grapes gets fermented in runs a close second.
We want our white wines to be acidic, zesty, and have floral aromas. We want our reds to be soft, rich, and velvety. At the start, the juice from both red and white grapes is somewhat unremarkable. You’d be hard pressed (excuse the pun) to taste and predict which will become a red or white wine.
The decider is oxidation. It causes red wines to lose their fruit and floral notes, and to take on smooth, nutty, richness. Winemakers encourage oxidation by using oak barrels to make red wines. Wood breathes. Winemakers reduce the exposure to oxygen during fermentation by using stainless steel tanks to make white wines. Metal does not breathe.
Back to the skin, again
Red wines are usually always described as having complex profiles. They make us think of berries, but then a list of secondary attributes that run the gamut from tobacco leaves to leather. Whites, on the other hand, tend to serve up a single citrus note, with maybe a secondary and more exotic tropical attribute. It’s not uncommon for someone to mention “pineapple” when talking about a white.
Red wines develop their profiles because of what exists only in the skins: tannins. Remember the apple? When you bite into an apple skin and feel your mouth pucker up, you’re experiencing the astringent phenolic compounds that make up tannins. These components are found in many plants, including grape skins.
Tannins extracted from grape skins during maceration are what create the foundation of the complex flavors we find in red wines. Tannins are also natural preservatives, which is why red wines can be aged much longer than whites.
Without tannins to impart complexity, white wines depend on developing the structure of acidity. The lack of tannins and oxidation creates higher amounts of acids, giving white wines their crisp, tart profiles.
They say beauty is only skin deep. Winemaking adds truth to this saying. When you remove the skin, you change more than the color of the wine you’ll make.