Gary’s Corner

Photo by Ian McCausland

Tasting Red

By Gary Hewitt, DipWSET, CWE, FWS, Sommelier

It used to be easy: red or white? Then pink became de rigueur, orange made a long-awaited (centuries!) comeback, and some chemists came up with blue (don’t worry too much about blue!). Certainly, colours help us categorize wines, but there is so much more to wine colour than immediately meets the eye.

Where does wine colour come from? The answer seems most obvious for red wines: black-skinned grapes contain pigments called anthocyanins that range in colour from red to blue. The pulp of these same grapes, almost without exception, is colourless. Therefore, red winemaking usually involves crushing the grapes to break the skins and liberate the juice from the pulp to create a juice-and-solids mixture called must. The skins then macerate in the must during fermentation, but possibly also before and after fermentation, to extract the pigment.

The amount of colour extracted depends upon many factors, including grape variety, vintage conditions, and the aggressiveness of maceration. As examples: Cabernet Sauvignon grapes have thick skins packed with pigment capable of giving deep, almost purple wines, whereas Pinot Noir grapes have thinner skins with less pigment that yield less intensely coloured wines of a ruby hue; warmer vintages lead to greater ripeness at harvest, which results in deeper colours. Winemakers also have many techniques to manage maceration and extraction, from manually punching down the grape skin cap into the fermenting wine to adding enzymes to weaken the cells in the grape skins, and even using rotary fermenters that turn like cement mixers to continuously submerge the skins in the must.

Surprisingly, the narrow red-to-blue colour range of extracted anthocyanins cannot account for the huge colour diversity of red wines. In fact, the anthocyanins as they exist in intact grapes last only hours or days after the grapes are crushed. Long-term colour is created during winemaking when anthocyanins bind, in particular, with tannins to form pigmented tannins. These colourful compounds are further subject to ongoing chemical reactions that occur as the wine matures in the bottle. Bottle maturation leads to the loss of purple-red pigments and a gradual fading of intensity as pigment–tannin aggregates become too large to remain in suspension and literally drop out of the wine to form sediment.

The overall result of this complex milieu is that “red” wines span an enormous spectrum of purple-violet-crimson-rubygarnet-mahogany-brown. Saying that wine is “red” is akin to asking for “red” at a paint store—next thing you know, you’re staring at a chart with hundreds of choices.

Understanding the complexity of colour helps technical wine tasters decode the provenance of a wine in blind tastings. Colour gives clues as to the variety, vintage conditions/ climate, winemaking, and maturity of a wine. For example, a medium-intense garnet (orange-tinged ruby) colour may indicate a mature wine or a younger wine made from a variety such as Nebbiolo, which is highly likely to be from Piedmont in northwest Italy. When considered in the context of aromas, flavours, and wine structure, colour adds to the evidence that allows for remarkable pronouncements not only of what a wine might be but what it must be. (Ah, Dr. Watson, there is method to the madness of blind tasting.)

But wine colour is more than chemistry and technology— psychology too is afoot. For example, if white wine is coloured red with a tasteless food dye, tasters find berry and dark fruit traits typical of red wines instead of the citrus and tree fruit character of the underlying white wine. Experts are often more susceptible to this deception than untrained wine tasters. The result is explained by the manner in which our brain forms our perception of flavour. Prior experience, such as repeatedly tasting cherry or cassis in red wines, creates the expectation of finding these traits in a new red wine, and this expectation overrides the information that our senses are actually supplying.

Wine producers take advantage of this quirk of the mind because many consumers associate colour intensity with wine quality. Highly pigmented preparations, most infamously a grape-based concentrate called Mega Purple, are used by some winemakers to add colour (and possibly sweetness depending upon the amount added) but not tannin. The perception is of a more full-bodied, flavourful wine. Other winemakers, for the sake of authenticity, refuse to use such additives.

It seems that colour is an aspect of our whole-mind construct of wine and not just a minor detail or technical clue to a wine’s identity. So next time you look at a wine, satisfy yourself that it is red, white, or other, and then release your inner wine geek to decipher the clues or your inner muse to create colourful poetry. Let the wine meet your mind’s eye.