What wine appeals more comprehensively to the senses than Champagne? It sparkles in the glass; it hisses slightly in your ear; its fragrance varies all the way from nutty to ripe pears to freshly toasted brioche; it hits your palate with a fine effervescence; and a great Champagne teases your tongue with a cascade of sensations before fading away with lingering slowness. Every sense that a wine can reach, Champagne will. Many fine sparkling wines are produced worldwide, not least in Italy and California; but once in a while there is nothing like returning to a fine bottle of Champagne.
Galileo Galilei is best known for his novel way of looking at Earth’s place in the solar system and his consequent problems with the Vatican. But long before all the fuss blew up over Galileo’s cosmology, he had produced a remarkable work called Il sagiatorre (The Assayer). Published in 1623, it ranged broadly across the sciences, with a focus on vision. And the science historians Marco Piccolino and Nicholas J. Wade have recently pointed out how innovative Galileo’s philosophy of perception was. Among other things, Piccolino and Wade quote Galileo as claiming that “we should realize quite clearly that without life there would be no brightness and no color. Before life came, especially higher forms of life, all was invisible and silent although the sun shone and the mountains toppled.” Galileo was saying that while the physical attributes of the planet are present, they are perceptually nonexistent until they have been interpreted by our senses. This theory applies to wine as much as to anything else, and Galileo, who described wine as “sunlight, held together by water,” did not forget that fact. As he put it in Il sagiatorre, “A wine’s good taste does not belong to the objective determinations of the wine and hence of an object, even of an object considered as appearance, but belongs to the special character of the sense in the subject who is enjoying this taste.”
What Galileo was perceptively telling us was that, to describe what a wine tastes, feels, looks, sounds, and smells like, we need to understand how the senses work. Anyone who has ever attended a wine event knows the five S’s of wine tasting: See, Swirl, Sniff, Sip, Savor. The five S’s allow us to hit directly three of our five senses—sight, smell, and taste. This leaves us with two senses that we rarely associate with wine—hearing and touching. But ignoring them is a mistake. There are few things more satisfying than the classic Pop! of a Champagne bottle, however déclassé purists may consider it (they prefer an unostentatious hiss). More important, what a person has heard about a wine usually influences his or her perception of it. In fact, the multimillion-dollar wine advertising industry depends on this aspect of wine appreciation. As for that fifth sense, touch is also critically important in how we perceive wine—not through our fingers but through touch sensors in our mouths and throats. If we couldn’t feel the wine in our mouths, our experience of it would be incomplete.
Let’s start with vision. Color is critical to the appreciation of any wine, and the presence of pigments in grape skins may derive from the vines having evolved traits to attract birds (which have exquisite color vision). Eyes have evolved more than twenty different times among living creatures on this planet, but it is a good bet that birds’ eyes and our own have a single common origin, and they certainly have many functional similarities. This being so, it is reasonable to suppose that in some sense we too might be predisposed by our biology to be attracted to the various colors of the grape. Humans appear to prefer reds over blues, greens, and yellows, and how we perceive red is important in the formation of our preferences in wine.
Light has had a complicated history of study. It was thought by some to be a particle and others to be a wave; in fact, the best way to describe light is both as a wave and as a particle. But it is the wave nature of light that allows our eyes to detect specific colors. Things appear to have different colors to us because our eyes and brains can detect very small differences in reflected light waves over a very small part of the wavelength spectrum. Visible light ranges from a wavelength of 0.4 micrometers (0.4 millionths of a meter) at the violet end of the spectrum to 0.7 micrometers at the red end. White light is a mixture of all of these wavelengths. Different colors in between occupy specific wavelengths within the spectrum of visible light.
Our perception that wine and other objects have color comes from the wavelengths of light reflected from them or passed through them. Ambient white light is made up of all the colors of the spectrum—red, yellow, green, blue, indigo, and violet. When we see something as white, we are actually seeing all of the colors of the spectrum fused together. And how an object appears to us is determined by which portion of this rainbow of colors it absorbs, or reflects. For instance, when white light hits it, a red grape absorbs all the colors of the rainbow except the light at the red end of the spectrum. That is reflected, so red is what we see. Similarly, a so-called white grape (actually, a green or slightly yellow grape) absorbs all the colors of the spectrum except the light in the green and yellow range.
The reflected wavelengths impinge upon sensitive cells in the retinas at the back of our eyes. And the story from there on out is largely a molecular one. The retina is like a cornfield full of long, thin cells called rods and cones. These are connected to nerve cells that are “wired” to a region at the back of the brain called the primary optic area. The rods and cones lie in close proximity to one another, but are structured differently and support different populations of proteins, which in their most relaxed state are simple linear molecules that look like beads on a string.
The workhorse of visual sensing is the category of proteins known as opsins. The opsins anchor themselves to the cell by winding through the cell membrane seven times. This interweaving leaves parts of the beads on the protein string exposed on the outside of the cell, while others are on the inside. When hit by light of specific wavelengths, a specialized part of the outside beads causes the protein to flip, from a form called cis to a form called trans. These flips are incredibly precise, and correspond to the exact wavelength of the light that has hit the retina. The jolt causes a chain reaction within the cell, and this is transmitted as an electrical potential to the nervous system and on to the brain.
The membranes of our rod cells contain rhodopsins, a specific type of opsin. When monochromatic light (light of a very narrow wavelength) hits the retina, the rod cells are stimulated. At night, all light is transmitted to the eye as monochromatic, so rhodopsin is an important component of night vision. In contrast, our cone cells have a choice between four different kinds of opsins, giving us four different kinds of cone cell. These four opsins are conveniently named long-, medium-, and short-wave sensitive, or LWS, MWS, and SWS1 and SWS2. Each of the four types of cone cell in the retina is like a switch that triggers a specific part of the brain to recognize that a particular wavelength of light has hit the eye. The LWS opsin detects light in the red range, the MWS detects light in the green range, and the two SWS opsins detect blue and violet.
Because of the versatility of these opsins in detecting light of different wavelengths, most human eyes are sensitive to subtle changes in color. But they can see them only if the opsin proteins that detect the different wavelengths of light hitting them are working properly; and most people reading this book will probably know someone who is red-green colorblind. (One out of every eight males of European descent has this condition.) These individuals cannot discern between the red and green colors hitting their retina, and hence cannot tell the difference in color between a glass of red wine and a glass of crème de menthe (without smelling it).
Individuals with only two of the four cone cell opsins will have dichromatic color vision. Only light that has wavelengths that excite the two kinds of opsins will be visible. In fact, most humans are considered trichromatic, even though they have all four opsins. This is because one of the SWS opsins is blocked by absorption, and hence is rendered nonfunctional. In the past decade, vision specialists have started to find individuals (all female) who are truly tetrachromatic, with four fully functional kinds of cone cells. These individuals see arrays of colors that are orders of magnitude more bountiful than the shades and hues in the 136 Crayola crayon box. Researchers have estimated that the addition of the functional fourth kind of cone cell allows these individuals to discern from a hundred to ten thousand times more colors, hues, and shades than trichromats can.
Wine appears to be red when it is full of anthocyanins, the family of chemicals which absorbs a specific wavelength of white light. Over 250 different kinds of anthocyanins have been found in plants, and they act as light sponges. They sponge up light most efficiently at wavelengths of about 520 micrometers. This means that all the green and yellow light is absorbed, leaving light waves of above 620 micrometers to be reflected to our eyes. The flip side of absorbance is transmittance: if, for example, the light transmitted through a glass of wine had a wavelength in the range of 650 to 700 micrometers, the wine would be very red.
If we were all tetrachromatic, we would easily detect extremely subtle differences in color—and would have developed a complex vocabulary to suit. But most of us are not, and we haven’t. So, in compensation, precise technical ways of detecting colors and hues in wine have been developed. As a result, the science behind how light is absorbed in wine is quite advanced, and winemakers are beginning to pay attention to it.
There are three major components to a wine color. The first is intensity. This involves simple quantification of how dark the wine is as a result of absorbance of light at three different wavelengths. A sample of wine in a small glass container is placed in a spectrophotometer. This machine blasts light of specific wavelengths through the wine and measures the light that emerges. The amount of light that makes it through is proportional to the amount of light-absorbing chemicals (such as anthocyanins) in the wine. Light is sent through the wine around three points in the visible light spectrum: 420 micrometers (violet), 520 micrometers (green) and 620 micrometers (red). The wine color intensity is the sum of the absorbencies at these three wavelengths.
The second measure of visual wine quality is hue. This is a technical measure acquired by taking the absorbance measured at 420 micrometers and dividing it by the absorbance at 520 micrometers. This measures the ratio of violet to green matter in the wine, which experts think is important. The third and most commonly used measure for assessing color integrates absorbance data taken across a wide range of the spectrum incorporating three aspects of color. The first of these is clarity, or luminosity (L: the up and down axis in the figure), which measures how white or black the wine is. This term is scored on a scale of 0 to 100, and the wine is whiter if the L is closer to 100, and blacker if it is closer to 0. The other two axes shown in the figure are known as a and b. The a axis measures the redness or greenness of the wine (a positive value is red, and a negative value is green), and the b axis measures the yellowness or blueness of the wine (a positive value is yellow, and a negative value is blue). In this way, the spectrophotometer acts like an accurate all-seeing eye, rather like those tetrachromatic women. But the machine doesn’t have the aesthetic reaction to the colors that the women presumably have.
The color axes for wine
So why would we want to know the color of a wine so exactly? For several reasons. First, the process of grape pressing and initial fermentation will have a huge impact on the overall color of a wine. Specifically, the amount of time the grape skins are in contact with the must affects the color of a wine, which in turn reflects how well the desired components of the wine have been extracted. This also has a direct effect on the fullness or body of a wine, so the winemaker can use color as a proxy for the heaviness or lightness of a wine. A wine in which color matches texture is a desirable commodity.
Winemakers have learned over the ages that color can also provide information on other important characteristics about the quality or texture or age of a wine. For example, the color of a wine is influenced by the amount of acid it contains. And for another, color is not a fixed attribute. As wines age, reactions occur among the various compounds and acids they contain: a red wine will usually evolve over time from a deep red to a tawny brown. White wines will tend to darken, until in really old wines it is sometimes difficult to know just from looking at a wine what its original color was. In addition, the vessel in which wine is aged may have an impact on the color, particularly if it is an oak barrel, which adds chemical complexity to the wine and affects its color as well as its aroma and taste. Finally, different blends of wines can be controlled precisely with careful color monitoring. And rosés benefit directly from the ability to assay color precisely.
The sense of smell is crucial to appreciating one of the principal features of any decent wine. And there are good reasons why wine tasters routinely smell a wine before they taste it. Our sense of taste is limited (we have five basic tastes), whereas our sense of smell is complex. Smelling a wine before tasting it can enhance the variety of sensations that can be extracted from a good wine, and can help the wine taster discern immediately the differences between a good wine and an excellent one.
Before getting to the specifics of how our noses work, we first need to understand the classic ways in which the nose has been used to appreciate and describe wines. Three terms are commonly heard in this context, aroma, bouquet, and odor, and each has implications for wine. Aroma refers to the fragrances that emanate from wine as a result of its basic chemical makeup. Bouquet, on the other hand, is used to describe the scents that arise from the processes of fermentation and aging: the products of the wine’s individual evolution. Odor is reserved for undesired smells and is usually meant to convey that something has gone wrong with a wine.
A developing wine is a potpourri of chemicals, such as sugars, phenols, and acids, and these can react with one another to produce new molecules. So the same wine will have a different smell at different stages in its development, although because most of these reactions occur early in the fermentation process, the major changes in aroma (and perhaps also in odor) will occur rapidly during this period. Changes in aroma slow down as fermentation proceeds.
The sense of smell is molecular, depending on the detection of particular molecules. And like all other molecules, those present in wine do not differ solely because of the different atoms of which they are composed. They also vary because those atoms are arranged differently, giving each molecule a characteristic size and shape. Imagine pouring a glass of wine. As soon as the bottle is uncorked, molecules from the wine start to float around in the air, though most stay close to the surface of the wine poured into the glass. There are billions of these airborne molecules, and there are hundreds of different kinds of them: alcohols, phenols, esters. Many of them float easily on the air because of their volatility, while others linger in the liquid and must be released by swirling the glass. At that point, our noses can begin to appreciate the complexity of the wine’s molecular makeup. In many ways, the air above a wineglass is like a box of jigsaw puzzle pieces waiting to be assembled into a coherent picture. This process begins in the nose, which rapidly sorts out the kinds and relative amounts of the molecules present, information that is then rapidly and efficiently analyzed by the brain.
So how is this done? Go to the mirror, tilt your head up a bit, and look into your nose. With a little light you can make out its lining, otherwise known as the nasal epithelium. If you could zoom in microscopically, you would see that this is covered in little hairs, known as cilia. The cilia are swimming in a thin layer (0.06 millimeters) of mucus that efficiently traps the compounds that emanate from your wine, allowing the cilia to get to them quickly. Once cells on the surface of the cilia come into contact with the compounds, a chain reaction occurs that is broadly analogous to what happens in the eye, though it is less well understood.
There are two major schools of thought among smell researchers. One view holds that the nose works using a lock and key mechanism. The compound comes in contact with the cilial cells, which have odorant receptors embedded in their membranes. Just as in the retinal opsins, part of these receptors protrudes outside the cell. When the compound comes into contact with an odorant receptor that has the right keyhole, it binds to the receptor protein. This causes the protein to change its shape, inducing a chain reaction in the cilia cell resulting in an electric potential that is duly transmitted to an immediately adjacent part of the brain called the olfactory bulb. Neurons in the bulb then interpret the kind of smell indicated by the original compound. Like sight, what hits our brains is what we smell.
A second possibility is currently championed by the biophysicist Luca Turin. Instead of the lock-and-key mechanism, Turin contends that the compounds we can smell vibrate, and different compounds vibrate in different ways. The vibrations cause the odorant compound to transfer an electron to the receptor on the cell surface of the cilia, triggering a response in the receptor that starts the chain reaction eventually detected by our olfactory bulbs.
Whichever mechanism is the right one, the ability to discriminate between the many different odorant molecules that hit the nasal receptors comes from having a huge variety of receptors. With sight, there are only four different kinds of cone cells. But the human genome contains around nine hundred odorant receptor genes, found in the hundreds of different kinds of cilia in the nasal passage. And this is why our noses can interpret with such clarity the hundred or so different compounds that wines may give off, in a mind-boggling array of combinations.
Asking, with the comedian George Carlin, “What wine goes with Cap’n Crunch?” might not actually be as trivial as it sounds. In fact, many people spend a lot of time worrying about which foods go best with which wines. This concern is not frivolous: the tastes in wine interact closely with all the other substances competing for the attention of our taste buds.
The process begins with the tongue. Take a glass of a nice, deep-red wine—for example, a young Cabernet Sauvignon. Sip it, let it bathe your tongue, and look in a mirror. Your tongue will resemble a field of little purple mushrooms or a mass of small purple pegs. These pegs are called fungiform papillae, and, though it’s not apparent to the eye, they are not all alike. Each papilla is made up of between 50 and 150 cells. At the tip of each bunch of cells there is an opening called the taste pore. Little hairs (microvilli) protrude from this pore and come into contact with the molecules emanating from the substance we have put in our mouths. The microvilli are actually cells that bear receptor proteins for the molecules that convey taste.
Our sense of taste has fewer receptor types than does our sense of smell. There are five major kinds of taste: salt, sweet, bitter, umami (or savory), and sour. Bitter, sweet, and umami tastes are detected in the same general way as smells. Thus, items that taste bitter and sweet emit their own characteristic small molecules. These are shed from items placed into the mouth, and interact with the appropriate receptors on the microvilli. This causes a chain reaction in the interior of the cell that is transformed into an electrical impulse. In turn, this impulse is transmitted by nerve cells out of the receptor cell and to the brain. Salt and sour, on the other hand, are thought to operate through a different set of interactions. Instead of binding to a receptor protein, salty and sour molecules change the concentration of electrically charged ions, and hence change the action potential of the membranes in the microvilli. These action potentials are in turn sent to the brain for interpretation, just as the action potentials from sweet, umami, and bitter tastes are.
Not long ago, it was thought that four distinct regions of the tongue tasted different things. Thus, bitter-taste detection was believed to take place at the back of the tongue; sour at the middle of the tongue toward the sides; salty on the edges of the tongue toward the tip; and sweet at the tip. And this way of thinking about taste regions on the tongue led some wineglass makers to reengineer their glasses according to principles that are now in question. The claim was that different-shaped wineglasses delivered fluids to specific parts of the tongue or mouth, and thus to particular taste detectors. Accordingly, manufacturers touted their products as enhancing the taste of wine drunk from glasses specifically designed for Chardonnays, say, or for Cabernets. One company claims that one of its glasses directs wine to the center of the tongue, while another delivers to its tip. The corresponding recommendation is that the former should be used for wine of intermediate acidity, and the latter for wines of higher acidity.
There may be some truth to such claims. But two discoveries have conspired to cast doubt on them. First, molecular analysis of the different taste receptors in the tongue has debunked the notion that this organ is partitioned into taste regions. The field of fungiform papillae on the tongue is made up of a heterogeneous distribution of papillae that detect the five different tastes without reference to region. The brain doesn’t care where on the tongue a food or beverage hits. Second, the fifth taste, umami, has thrown a wrench into the works. Umami is involved in how we taste small molecules called glutamates. These occur in wine, and yet the “region-specific theory” of taste on the tongue has no umami region.
Drawing of a tongue showing the rough surface of the tongue where taste receptors reside. One of the early theories of tongue taste receptors suggested that the receptors for four of the five kinds of taste were localized on the tongue. But this theory has been dropped.
How we combine the tastes and styles of wine and food has recently become big business, though basic commandments about combining food and wine have been around for decades. The first commandment is never to consume wine with garlic, spice, vinegar, or raw fruit. These foods tend to overwhelm the subtle taste of wine. And if you think about the receptors in your mouth that transmit taste sensations to your brain, the prohibition is easy to understand. Garlic, spice, vinegar, and raw fruit are all full of molecules that will react easily and strongly with the receptors of your tongue, leaving few receptors available to register the taste of wine. Something similar applies to other strong or greasy foods, such as pungent Stilton cheese or fatty foie gras. According to the second commandment, you will have to pick your wine carefully for these—sweeter wines, such as Port and Sauternes, respectively, are usually recommended. The third commandment is never to drink white wine with red meat or red wine with fish. That injunction was always on shakier ground, and nowadays, when it’s not unusual for a chef to poach a filet of turbot in red wine, it is entirely negotiable. The basic challenge in drinking wine with food is to match the precise flavors and textures of the wines and foods involved.
So the real test is to determine the combinations of food and wine that will best enhance the taste of both. And understanding the five basic taste receptors and how to stimulate them will open the way to more enjoyable and appropriate combinations. So, for instance, if you are eating a salty dish, you might want to stay away from a wine that stimulates the salt receptors. But also keep in mind that if you eat salty food and drink a sweet wine, that wine will taste sweeter than usual. This is because the salty food will have blocked the majority of your salty-taste receptors, and the tongue will ignore the salt in the wine, even as it is detecting all the sweet molecules. Your available receptors will taste only sweet, which will thereby appear to be much more intense than if you had started with a clear palate. When eating sweet food, on the other hand, an acidic or heavy-textured wine might be best. Chefs have become creative in their wine and food pairings in recent decades, but whether we recognize them or not, successful pairings will invariably draw on the invisible chemical principles of our taste receptors.
Glasses of different shape do direct fluids to different parts of the tongue, although it is not clear whether this attribute of the glass has much effect on the taste of the wine it contains. But where the wine hits the tongue is not the only purpose of differently shaped wineglasses. Even informal experimentation will prove that the glass enhances the sensory experience.
One of the most important features of a wineglass is its thickness, an attribute that underscores the importance of the sense of touch in the overall experience of drinking wine. A thick, clumsy, rounded rim will blunt the experience of drinking any wine, however expensively engraved the cut-glass receptacle may be. A thin, cleanly ground rim, on the other hand, will impart a degree of definition not obtainable any other way.
Also important is the size of the glass’s bowl. Direct experience of a wine comes not only through taste but also through smell, and wines need space to oxidize and expand in the glass, and to release the aromatic and volatile molecules that will stimulate the olfactory receptors. Larger glasses have more than an edge here, especially for red wines. The glass also needs to be shaped in such a way that it can trap and concentrate the rising molecules for appreciation by the nose. It is more debatable whether red wineglasses need be the enormous balloons favored by some who attend commercial wine-tasting extravaganzas, or whether specific varietals need to be savored from glasses of different sizes and shapes.
But what we can affirm is that while compact receptacles such as the tulip-shaped 7¼-ounce (215 ml) official glass of the French Institut national des appellations d’origine et de la qualité may reduce clutter at tastings, and produce a level playing field, they are not big enough to bring out everything a wine has to offer. A better general solution is the similarly shaped but larger (12 ounce, or 350 ml) all-purpose glass in thin crystal available relatively inexpensively from several manufacturers. Some insist that red wines demand an even larger or more open bowl. With your own unique sensory anatomy, only you can decide by trial and error which glass—or range of glasses—is right for you. Fortunately, there are many choices.
One type of wine clearly demands a glass of specialized shape: the sparklers. In the past few decades the spill-prone open goblet, supposedly modeled on Marie-Antoinette’s breast, that ensured the most rapid possible dissipation of the bubbles in Champagne and other sparkling wines, has been largely abandoned. The tall, narrow flute has eclipsed this cumbersome vessel; it provides maximum visual satisfaction in watching the bubbles rise, and it preserves them for a longer period of time. Still, elegant and compact as the flute is, it has its critics. An excessively narrow flute, it is argued, will dull the aromas of a sparkling wine and accentuate its acidity. Accordingly, many experts advocate tulip flutes, which are broader in the beam than regular flutes and have a somewhat wider opening. Our favorite is a broadish flute with a hollow stem, which lets the drinker enjoy watching the bubbles rise all the way from its foot.
As Gérard Liger-Belair reveals in his engaging Uncorked: The Science of Champagne, those bubbles—which are composed of carbon dioxide gas that had been in solution, under pressure, before the bottle was opened—require impurities on the glass in order to form. A bubble needs to nucleate in a vacuity that is at least 0.2 micrometers across, and nowadays, with advancing technology, manufacturing defects in the glass itself are typically smaller than this. So in theory, if the flute were perfectly clean, not a single bubble would form in Champagne. All the gas would escape directly into the atmosphere from the surface of the liquid, rather than rising in those mesmerizing bubble streams from below. Hurrah for imperfection!
Having considered the senses we come to the brain, the hugely complex organ within which all that sensory information is processed and synthesized. We don’t just taste with our senses, we taste with our minds. And our minds are routinely affected by a host of influences of which, quite often, we are not even aware. Both our senses and our common sense can be led astray by any number of extraneous factors originating in what we know, or think we know, about the wine we are drinking. Figuring out how our minds work in such complex domains as the evaluation of wines—which are, among other things, economic goods—is the province of neuroeconomics.
To study the relationship between consumer preference and, for example, the cost of wine, neuroeconomists typically set up blind experiments, in which the subjects are unaware of the parameters of the experiment. Researchers at the Stockholm School of Economics and Yale University recently conducted a double-blind experiment—in which both the subject and the experimenters with whom they come into contact are unaware of the parameters involved—upon this relationship. Their sample of over six thousand subjects included experts, casual wine drinkers, and novices. The experiment was simple. Subjects were asked to taste a succession of wines and rate them as Bad, Okay, Good, or Great. The wines ranged in price from $1.65 to $150, and the subjects were not told the cost. The responses for each wine were tabulated, and statistical analyses applied. Now, the average wine buyer might have hoped that this experiment would show that the price of a wine is correlated with its quality. This would certainly simplify life. But the researchers discovered that “the correlation between price and overall rating is small and negative, suggesting that individuals on average enjoy more expensive wines slightly less.”
To explore this relationship further, researchers at the California Institute of Technology set up an experiment in which they examined not only the dynamics of preference but also which regions of the brain might be controlling such preferences, in light of cost. To localize these, they turned to a technique known as functional magnetic resonance imaging (fMRI). The tough part of using this method on taste judgments is that the subject has to lie completely still, so the researchers had to devise a pump-and-tube system (a long way from those crystal glasses) to deliver the wine to their subjects. Then the researchers threw a complication into the study that allowed them to pinpoint whether knowledge of price affected perceptions of taste.
Pricing Data in Caltech Neuroeconomics Experiment
Offering |
Price |
Price revealed to subject |
1 |
$90 |
$90 |
2 |
$90 |
$10 |
3 |
$35 |
$35 |
4 |
$5 |
$5 |
5 |
$5 |
$45 |
First, they bought Cabernet Sauvignon from three different vineyards: an expensive $90 bottle, an intermediate $35 bottle, and a rock-bottom $5 bottle. Their subjects were all young males (aged twenty-one to thirty) who both liked and occasionally drank red wine, but were not alcoholics. They placed the subjects in their MRI machine, connected the delivery hoses, and told them they were going to taste five different kinds of Cabernet Sauvignon. For each of the offerings the subjects were told the notional cost of the wine (as listed in the table), and then the wines were pumped into the subjects’ mouths in a predetermined sequence, for a set amount of time. Subjects were then asked a series of questions designed to determine their preference for each of the “five” wines. The experiment confirmed that perceived wine cost was a heavy factor in choosing preferences. But the real revelation was that a region of the brain called the medial orbitofrontal cortex was hyperactive in every one of the subjects while he was making his choice. It seems that we all use the same part of the brain to make decisions about wine, at least when money is involved.
This experiment clearly showed that the subjects’ preferences for the wines used in the study were strongly influenced by what they believed the wines had cost, and that this calculation was processed in a specific part of the brain. That’s a start. But the subjects were relatively young and naive about wine tasting, and one might legitimately wonder whether an expert wine connoisseur would have been tricked in the same way. This experiment has not been performed yet, at least with an fMRI machine. But it seems likely from the literature that prior knowledge is a significant factor in most people’s appreciation of a wine.
The psychologist Antonia Mantonakis and her colleagues looked at preconceived notions from another perspective. Before giving the subjects wine to taste, the researchers first planted in their subjects’ minds either the notion that they had previously “loved the experience” of drinking wine or that they had “got sick” from it. Whether the subjects actually remembered their earlier drinking experiences in either way was irrelevant to the experiment, since virtually everyone has had experiences of both kinds at some time in their wine-drinking lives. What was important was the initial suggestion offered to the subjects. And the outcome was perhaps to be expected: people who were given the positive suggestion were more influenced by it in rating the wines than those who were received the negative one. Clearly, the tasters’ responses were affected by extraneous factors, and the researchers concluded, logically enough, that if wine retailers wished to appeal to their customers’ personal experiences of wine, they should try to call up the most pleasant possible associations.
Neuroeconomists have also been able to demonstrate by experiment something that has long been understood from anecdotal experience—namely, that our perception of wine is influenced not only by what is in the bottle but also by what we see on the label. Researchers in Barcelona and Paris conducted blind experiments in which they evaluated the role of the shape and color of the label in forming consumers’ preferences for wines. Although both variables were significant in consumer choice, the colors of the labels were less important than their shapes, or the shapes printed on them. The most successful labels were brown, yellow, black, or green (or combinations thereof), with rectangular or hexagonal patterns. You might ask whether preconceived notions of cost might have affected the outcome of the experiment. But since the researchers also discovered that there was no correlation of cost with label preference, the experimenters felt confident that their conclusions were valid.
Does how much you know about wines in general influence how you perceive a specific wine? And what is the value of a name? To assess at least the first question (getting at the second would presumably have been too expensive), researchers gathered experts, moderately informed wine drinkers, and novices, and presented them with an advertising campaign for a particular wine, a Zinfandel, before the tasting. The variables in this case were the quality of the wine as assessed by external experts and the preferences of the subjects. In all cases, the experts were unswayed by the mock advertising campaign, while the novices were influenced by it in making their choices. But what was most interesting was the reaction of the moderately informed wine drinkers. These subjects chose the same wines as the experts if, before issuing their judgments, they were allowed to consider both the ad campaign and what they knew about wine. Given time to consider their choices, they were able to set their preference based on the quality of the wine. But if rushed and not allowed time to think, they turned in the same results as the novices.
The results of the initial experiment prompted the researchers to repeat it with only novice wine drinkers. But now, before the tasting began they educated their subjects for twenty-five minutes about wine and its quality. These novices turned in the same results as the moderately informed group had done in the first experiment; and in this case, too, the key factor in judging the quality of the wines correctly was allowing the subjects to think about what they had been told in the training session.
On one level, experiments like these show that advertisers are learning more and more about what influences our choices in wine, and that they are going to find ever-subtler ways to influence people to buy their products. Consumers thus need to be on guard, because it is clear that how one experiences a wine is affected by a host of factors, some of which might seem to be irrelevant. (Mantonakis and her colleague Bryan Galiffi even showed that consumers significantly tended to prefer the products of wineries with hard-to-pronounce names!) The good news in all of this, though, is that if you educate yourself on what constitutes a good wine and you use this knowledge as a standard when tasting a new wine, you will more often than not be able to judge its quality accurately.
By the time you’ve swallowed a sip of wine, then, it will have engaged all five of your senses. In fact, a great wine is capable of delivering one of the richest multidimensional sensory experiences you will ever have—also, regrettably, one of the most expensive. Indeed, however you may score or describe the color, the clarity, the nose, the taste, and the mouth-feel of a wine, the end product will inevitably be summed up by just one number: the price. Although price and expectation go hand in hand, price and quality do not necessarily do so. It’s a confusing market. So it’s hardly surprising that a profession has grown up around the sensory evaluation of wine as an aid not only to its production, but to its consumption.
Once upon a time, the top wine critics were English. They were, by and large, aesthetes who celebrated wine as part of a much larger total experience of life. They tended to describe the wines they evaluated in relatively abstract and stylistic terms: a wine was aristocratic, lean, restrained, or voluptuous. Eventually they began ranking wines by awarding stars to them (usually between 1 and 5), and then, as the profession became a little more focused, by adopting a 1 to 20 scale. Those rankings were a bit like the 1855 Bordeaux classification described earlier: they had a tendency to reinforce a hierarchy that already existed.
Then came the Americans, led by Robert Parker. A lawyer by training, Parker started his career as the world’s most influential wine critic by publishing a wine newsletter, and he became well known when he was faster than most of his rivals to single out 1982 as a classic vintage in Bordeaux. After this triumph, his Wine Advocate newsletter began to circulate widely in the trade.
Like his British counterparts, Parker carefully described the wines he rated, although he used a different vocabulary, based less on style than on a wine’s immediate impact on the taste buds. Suddenly, wines were jammy or leathery; they tasted of herbs, olives, cherries, and cigar boxes. But the most important ingredient of Parker’s formula was to rate wines on a scale of 50 to 100, exactly as his readers had themselves been rated for their performance in high school. No wine could score below 50, and between 50 and 60 a wine barely rated mention. A wine that scored between 70 and 79 was merely average; it had to score in the high 80s to merit serious attention. Here was a scale with which all Parker’s readers could identify, and although detractors railed (correctly) that such a finely graduated scale was ridiculous, there is no doubt that Parker has a highly discriminating palate and knows a good or interesting wine when he tastes it. What’s more, when he established his newsletter he deliberately eschewed commercial sponsorship, and he paid for all the wines he tested. This was not true of Wine Spectator, a magazine that, after a lean start on newsprint, today rivals the glossiest of glossies in its production values, driven by lavish advertising, principally of high-production wines in the mid-to-upper segment of the market. Wine Spectator uses Parker’s 50 to 100 scale, recommending only wines scoring above 75. Unlike Wine Advocate’s practice, however, Wine Spectator’s wines were usually evaluated by committee, at least until some of its leading lights became minor celebrities in the wine world, averaging the scores of several tasters.
The numeric scale gives wine ratings an aura of impartial objectivity. But, as human beings, Parker and the editors of Wine Spectator remain creatures of preference. Rating something as diverse as wine by such a system is a bit like asking someone to rate blues and yellows on the same preference scale: it can be done, but where each color tone will score entirely depends on which appeals more to the viewer. Still, there is enough agreement on what makes a wine great, or better than another, that a several-point spread will usually mean something significant to most people.
So the Parker rating scale caught on quickly. No longer did the wine buyer have to decrypt a critic’s lyrical description to decide whether he or she would actually like the wine described; now it was as simple as picking a wine that Parker had rated over 90. In turn, this meant a huge surge in demand for the wines that Parker liked, and prices for them rose accordingly.
Several years ago, as wines he had been accustomed to drinking regularly skyrocketed out of his financial reach, one of us rather sourly remarked to a wine merchant that he, at least, must have been happy with the Parker-driven price rises, which had presumably increased his margins. “Not at all,” he replied. “If Parker gives it over 90 I can’t buy it, and if he gives it less, I can’t sell it.” In its way, this is just as sad as the remark once made to us at a dinner party by an excessively affluent guest who declared that he only drank “the greatest” wines. Life, he said, was too short to drink anything else. It turned out that what he meant by “greatest” was actually “highest-scoring” and “most expensive.” Well, if ever a strategy were designed to cut people off from the captivating variety that is the most intellectually entertaining and sensually rewarding aspect of drinking wine, this must surely be it.
Parker has always preferred lush, powerful, in-your-face wines like those produced in the Rhône Valley or in the Merlot-dominated regions such as Pomerol and Saint-Émilion that lie to the east of Bordeaux. And so pervasive did his influence become that producers all over the world began to use the technologies available to them to produce alcoholic, fruit-forward wines that would score high on the Parker scale. Out the window went ideas of terroir, replaced by a search for the wine that would score a perfect 100 on the Parker scale. An analytic laboratory was even established in Sonoma that, for a fat fee, advises all comers on how to produce a Parker 90+ wine.
The world is not a static place, however, and the Internet has changed the rules of the game yet again, allowing a huge chorus of pundits a voice and simultaneously creating a more perfect market that has taken away much of the thrill of the chase. In what we can presumably take as a nod to the times, even Parker not long ago sold a stake in his newsletter to Singaporean interests. But there is no doubt that Robert Parker’s precise attention to numbers and his detailed criticism caused fine winemakers worldwide to pay extra attention to both the growing of their grapes and their winery procedures, and it contributed to a general rise in standards that was also driven by improvements in technology.
However high those standards might have been, though, this dynamic also promoted a growing worldwide uniformity of style, leading many to lament the increasing “globalization” of tastes in wine. If you have not seen the movie Mondovino, do so: its production values may not be the greatest, but its message—that the soul of wine is being lost as an internationalized mass market develops—comes straight from the heart.
Another effect of globalization has been to turn certain varietals into stars, sidelining the rest—although some, such as the Galician Albariño and the Campanian Aglianico, are making a comeback in boutique circles. As recently as the 1950s, few vignerons outside Burgundy were growing Chardonnay or Pinot Noir grapes, and the bulk Chablis and Hearty Burgundies that then accounted for so much of California wine production had never seen a Chardonnay or Pinot Noir vine. But nowadays, if you browse the wine list of any decent restaurant you will almost certainly find both varietals on offer from a bewildering array of vineyards around the world, while you will probably look in vain for a Savagnin. Yet although Pinot Noir character always contrives to shine through even in inferior versions, Chardonnay is remarkably responsive to circumstances. In different hands and places it can produce entirely different wines, making Chardonnay in a sense the ideal globalized varietal.
And of course, the fact that to the high scorers went the high prices was not lost on winemakers. In a world in which technology made almost anything possible, and the high numbers and big money often went to alcoholic fruit bombs, the winemakers duly followed, in a process lucidly captured by Paul Lukacs in his excellent history Inventing Wine. But for every action there is an equal and opposite reaction, and it is a rare pendulum that swings only one way. Some knowledgeable commentators are beginning to predict a shift in wine drinkers’ preferences toward leaner, less alcoholic, more elegant wines, in which the balance has shifted toward structure and away from the fruit. We won’t be sorry to see such a shift take place, although we wonder how it will fit in with climate change, something we’ll discuss in Chapter 12.
Those nostalgic for the days when even people of modest means could occasionally afford a top bottle of wine might not think any development entirely bad if it lessened demand for better wines, and consequently lowered their prices. But at the same time winemakers need an incentive to lavish on their product the labor and investment necessary to achieve optimum results. Standards have improved as the returns on making good wine have risen. Nostalgia aside, the average table wine of our youth wasn’t a patch on its modern counterpart, and it is not so long since most wine was rather pitiable stuff, the main attraction of which was that it was relatively safe to drink and/or got you tipsy.
This is good news for the average wine drinker who has just started exploring wines, or who can contrive to forget what he or she used to drink. Just as well, because the most expensive and highly reputable wines are becoming more and more significant as investment vehicles. In an avaricious world in which lucrative returns on capital are becoming harder to find, not only extravagantly wealthy individuals but even major hedge funds are buying prestige wines for their appreciation potential. What this means in practice is that much of the production of the top wines may increasingly disappear straight from the château (to avoid fakery problems) into climate-controlled storage, where it is likely to stay, occasionally changing hands at auction, until it is well past its prime.
Unfortunate as this may sound to those who think of wine drinking as a conduit to some of the most refined pleasures in life, it is hardly more tragic than the collecting and serving of wines purely as prestige items. This is increasingly happening all around us, as top wines become fashion accessories used to impress instead of being appreciated for their intrinsic qualities. The trend is accelerating, as vast quantities of top wine flood into affluent new markets where wines have not traditionally been drunk or enjoyed, and where, as the neuroeconomists understand so well, a bottle is likely to be appreciated far more for its price and label than for its contents.
