Despite being odorless and tasteless, body is an important character in wine. It adds to, or detracts from, our pleasure in drinking. In blind tastings, body provides a clue as to varietal and regional origin. It is a key factor in wine and food pairing too, ideal matches being similar in weight. But what is body in wine and what do descriptions of body mean?

What is body in wine?

Body is the perceived thickness of a wine in one’s mouth. Think about how water feels in your mouth. Now think about vodka. Vodka feels more viscous than water because of the alcohol content. Maple syrup is much thicker than water because of dissolved sugar.

The amount of body in a wine is determined by the levels of alcohol, sugar, other soluble fruit extract (pectin, phenols, proteins, etc) and acidity. Perceived viscosity increases with the content of the first three elements. The acids in wine are less viscous than those other elements and the higher the  acidity the lower alcohol tends to be. Therefore, wines with a lot of acidity tend to be lower in viscosity than their lower acid counterparts. However, some high acid wines are also very high in sugar and can therefore be full-bodied.

Why does alcohol feel more viscous than water? The longer a molecule and the more easily it creates hydrogen bonds, the more viscous it will be. Water bonds readily but is the smallest of molecules. Therefore, water molecules aren’t easily “tangled” with others. Ethyl alcohol feels thicker because its molecules are larger and it also bonds easily.

To understand how these larger, easily tangled molecules create the sensation of viscosity, lets use an opposite example. Think of walking through a pool of chest-deep water wearing only a tight-fitting swimsuit. Now think about walking through the same water while wearing a lot of loose-fitting clothing. The water hasn’t changed, but it feels more viscous because your clothing is bulkier, more easily tangled and provides more resistance.

A water molecule. Water makes up the vast majority of a wine’s volume. Water molecules are relatively streamlined.

Ethanol is the primary alcohol in wine. Here’s an ethanol molecule. It’s much larger than water (these graphics aren’t to scale) and more easily snagged by others.

Describing Body in Wine

There is an assortment of semi-confusing (or entirely confusing) wine-speak descriptors for body. Without formal training or a secret decoder ring, quantitative descriptions such as “medium-plus” seem abstract. Qualitative comments—lithe, supple, luxurious, opulent—are poetic but only a little more helpful.

Here’s a table showing the five standard “quantitative” descriptors, their association with different types of milk—a convenient reference—as well as some common, creative descriptors. Some adjectives fall into more than one range. That’s because their use varies by varietal. Napa Valley Cabernet Sauvignon may be elegant at medium+ body whereas Beaujolais Nouveau may not. Some descriptors also have multiple applications. Feminine may refer to body in wine, but also to aromatics, structure and balance. There are also a lot more evocative celebrations of full-bodied wines than those of medium body or less. That’s indicative of both the relative scarcity of high-quality, light-bodied wines and of what critics tend to prefer.

The 5-point scale of wine body, from light to full, is useful but we have to remember that wine is analog not digital. In the real world there’s a smooth continuum of increasing weight from light through full. Terms such as medium+ express a range of possible viscosities, not a single specific consistency.

Not all these values have the same dynamic range either. “Medium” is narrow, in part to combat our natural tendency to play it safe by calling everything medium. “Light” is a smaller range than “Full.” That’s because there is a finite limit to how little body a wine can have but the ceiling for body is quite high. The ranges blend from one to the next. There are no absolute dividing lines between them.

Body changes with serving temperature; the warmer the wine the more viscous it is. Body also varies depending on the wine and the type of food, if any, with which it is paired. For example, very tannic wines will seem smoother but more full-bodied when eaten with a rib-eye steak.

Candidates for advanced wine certifications are required to pinpoint just one body designation for any given wine. Wine reviewers often use a two-step range for body in wine though, because they don’t know the conditions under which a consumer will be tasting. I often use the slightly more precise “nearly full-bodied” to indicate that a wine is on the border between medium+ and full.

One of my pet peeves is wine reviews which express a three-step range for a wine. I see this frequently, even from celebrated wine advocates. They’ll tell you a particular red wine is “medium to full-bodied.” Virtually all high-quality red wines from the New World, and most from the Old World, fall into that range. It’s like saying a particular breed of cat has fur. Not terribly illuminating.

Copyright Fred Swan 2016. Photo multimotyl: Wikimedia Commons. All rights reserved.