UNDERSTANDING THE PERCEPTION OF WINE

Jamie Goode, www.wineanorak.com

SYNAESTHESIA: THE JUMBLING OF THE SENSES

The Man Who Tasted Shapes (1993), Richard Cytowic

Michael Watson: “there aren’t enough points on the chicken.”

Flavor associated with shapes

Lexical synethesia the most common:words prompt experience of colors

What does it show us?

PERCEPTION OF FLAVOR IS MULTIMODAL

COLOR AFFECTS FLAVORWhite plates enhance sweet flavors, black plates bring out more savory flavors, and red plates reduce the amount that people eat

Experiment: artificial lighting, steak was actually coloured blue: result?

COLOR-SMELL ASSOCIATIONS

Avery Gilbert & colleagues (1996): 20 test odors

Asked people to describe them using color

Stable (2 yr) significant associations

Dematté and colleagues (2006): choose color to match odor - people consistent in their choices

People responded quickest to color-odor pairings with a strong association

Gottfried and Dolan (2003): visual cues help people identify smells when the picture matches the smell

COLOUR AFFECTS WINE PERCEPTION

Very hard not to let the colour of wine influence our perception

Will even lead us in our choice of descriptors

Morrot et al famous experiments with coloured wine

By the time we come to taste, we are already heading in a certain direction

How reliable are colour cues?

How do we deal with orange wines? With lighter reds? Is culture important here?

DIFFERENT AESTHETIC DOMAINS RELATED THROUGH EMOTION?Palmer & colleagues, Univ Calif Berkeley

Asked whether the color-music association is mediated by emotion

Choose best and worst color-music associations

Emotional ratings of color choices matched emotional ratings of music selections

Emotion may be mediating these associations

THE TONGUE

Five (six?) basic tastes:Sweet, sour, salty, umami, bitter (also fat?)

Touch: astringency, hot, cold, texture

Lubricated by saliva (complex mix of proteins/carbohydrates)

Flavor localized by sense of touch

HOW WE SMELL• Orthonasal and

retronasal olfaction• c. 400 olfactory

receptors• Each olfactory

receptor neuron has a single type

• So how do we distinguish 1000s of different smells?

OLFACTION: PATTERN RECOGNITION

Chirality: mirror images of same molecule can smell different

Carvone – can be spearmint or caraway

Deuterated analogs can smell different: eg Acetophenone

Pattern of activation: eg 3 million hairs, each with a mechanoreceptor – we recognize patterns of activation

Object recognition: eg Coffee – complex mix of aromas that can vary, yet we recognize coffees that are very different as coffees

OBJECT RECOGNITION

RECEPTOR SPACE VS PERCEPTUAL SPACE

Dimensionality of olfactory receptor space is not the same as that of the perceptual space

Receptor space: 400 receptors, the binding sites of those receptors, the downstream signalling

Perceptual space: influenced by evolutionary constraints: what our sense of smell needs to do for us to succeed

DESENSITIZATION AND CROSS-ADAPTATION

Desensitization: we can enter a room or a home and find it noticeably smelly, but after a while we get used to the smell.

Important ability: the strong smell would otherwise override more subtle smells.

Cross-adaptation: the process of adaptation to smell x causes some adaptation to smell y.

While desensitization is problematic for wine tasting, cross-adaptation is a greater hazard.

CLAUS WEDEKIND’S SMELLY T SHIRT STUDY

PERCEPTION: WE GET THE EDITED HIGHLIGHTS

CEO

minion minion minion minion

THE CAFÉ WALL ILLUSION

A PERFECT MAP

100% representation would be a terrible map

A perfect map is an abstraction that gives us just the information we need

THE ARTIFICIAL INTELLIGENCE APPROACH

How would you create and AI with the ability to perceive the world?

• Vision: a camera, face recognition etc.

• Sound: a microphone/recorder, speech recognition etc

• Chemical senses: measuring devices

• Touch: pressure sensors

CONSTRUCTING REALITY

Dreams and hallucinations: states of mind where we experience our own reality

Could these states reflect the ability of the brain to construct reality from limited sensory input?

Is what we experience of reality actually something that we construct around a skeleton of reality that we extract from the world around us?

PREDICTIVE CODING

Hot topic in neuroscience

Based on Bayesian statistics (Thomas Beyes)

We create a model of the world around us

Then refine that model by using error messages

OUR BRAIN CREATES ‘REALITY’

INDIVIDUAL DIFFERENCES

PROP TASTERS AND SUPERTASTERS

BITTERNESS

Humans have 25 bitter taste receptors

TAS2R38 - detects PROP - is just one of them

TAS2R31 detects the bitterness of artificial sweeteners acesulfame-K (AceK) and saccharin

TAS2R31 is responsible for detecting the bitterness of quinine and also corresponds to grapefruit liking

TAS2R3/4/5 can explain the bitterness that some people experience with alcohol

Bitterness is not a monolithic trait

THE ROLE OF SALIVA

Mainstream explanation for astringency perception is the delubrication hypothesis

Saliva contains proteins that lubricate the mouth, and tannins bind to these proteins and cause them to precipitate out

This strips the lubrication and we sense this change as astringency

People differ widely in their salivary flow rate. The more saliva, the less astringent we find tannins

People differ in their ability to replenish salivary proteins. As a result, some people are much more sensitive to astringency and like astringent foods and drinks much less

INDIVIDUAL DIFFERENCES (2)

Rotundone: AWRI recently identified this as the compound responsible for the peppery character in red wines, especially cool climate Syrah – 20% don’t get this

OR10G4 gene explains differences in responses to guiacol, a smoky aroma - might also explain the different reactions of people to 4-ethylphenol and 4-ethylguiacaol

OR2J3 gene influence how intensely people experience cis-3-hexanol, a grassy aroma

OR5A1 affect the way that the floral-smelling beta-ionone is experienced (with a genetic association that means that roughly a quarter of the population are insensitive to the violet/floral aromas found in some wines)

ANDROSTENONE AND ORD74Androstenone is a smelly steroidal compound produced by pigs that is described as sweaty, urinous, and musky by those who can smell it. Depending on the version of the OR7D4 gene people have, they nd androstenone unpleasant, or sweet, or they cannot smell it at all

Kara Hoover looked at sequences for OR7D4 in 2,200 people globally - Gene subject to evolutionary selectionInsensitivity to androstenone changes though adolescenceAbility to smell it can be induced by exposure - surprising for a trait that has a strong genetic componentThis suggests those who cannot smell it might still be able to detect it unconsciously, and that somehow this induces sensitivity, perhaps by a affecting the number of olfactory receptors that can detect it, so that more are made.

IMPLICATIONS

We are all different

Is it possible to segment people according to these differences?

Where does this leave wine tasting, judging and wine exams?

These individual differences are countered by learning

We must move beyond simple hedonics

‘Community of judgement’ – we decide together what is good

EXPERIENCE: NOVICES VERSUS PROFESSIONALS

Sommelier studies: using brains differently

The first wine that appealed to you: would it taste different today?

Heraclitus: no one steps in the same stream twice

Knowledge shapes the actual perceptive event: fMRI study - Presented with $5 wine (wine one, at its real price); a $10 wine (wine two, which was actually a $90 wine); a $35 wine (wine three); a $45 wine (wine one, at a false price) and a $90 wine (wine two, at its real price).

A correlation between price and liking: subjects preferred wines one and two when they were told they were drinking the higher-priced wines. Parts of the brain that experience pleasure are more active when subjects think the wine is higher priced

Our expectation as we approach wine—perhaps caused by sight of the label—will actually change the nature of our wine-drinking experience.

WINE TASTING IS ODD

Barry Smith, codirector of the Centre for the Study of the Senses at University of London’s Institute of Philosophy, comments:

“Serious wine tasters are trying to undo the brain’s work, which is a crazy thing to be doing. The brain has beautifully put all this information together for you below the level of consciousness, so it appears in your experience as an integrated unified whole. Then what tasters do is pull those bits apart again and make themselves notice them. What is the texture like? How ne are the tannins? What is the astringency? Which acids or sugars am I getting? How do the aromas persist? It is trying to look behind the curtain, by reflection from the top level. If they weren’t integrated, you’d have all that information lying around in bits: they would be there for you to notice separately. But the brain’s job was to find the thing that has got all of that together, and tell me how collectively it tastes. So wine tasting is odd.”

BROCHET’S WORK

Authors’ descriptive representations are based on the ‘types’ of wines

They are “prototypical” - specific vocabularies are used to describe types of wines, and each vocabulary represents a type of wine.

The range of words used (or lexical fields) are different for each author

Tasters possess a specific vocabulary for preferred and nonpreferred wines

Color is a major factor in organizing the classes of descriptive terms used by the tasters

Cultural information is present in the sensorial descriptions.

HOW DO NOVICES AND EXPERTS DIFFER?

Better at tasting? Or just better at using sensory information?

Jordi Ballester (University of Bourgogne, Dijon)

“Novices use basically bottom-up processes, which means that they take most of the information from the sample itself since they have very little information to bring to the tasting besides affective hedonic judgments.”

“In terms of detection (sensitivity), experts are not more sensitive than novices for alcohol or tannin perception. They do not have better olfactory equipment than novices.”

“Experts’ superiority is due basically to their improved cognitive ability, for instance, the ability of focusing on attributes that according to their knowledge would be relevant in a given tasting.”

EXPERTS VERSUS NOVICES

HOW WE TASTE WINE IN PRACTICE

THE LANGUAGE OF WINE

Linguist Guy Deutscher, Through the Language Glass (2010): how does language shape our perception?

Dominant, “nativist” view in linguistics: language is an instinct - the fundamentals of language are encoded in our genes, and are universal across cultures. People are born with a linguistic toolkit, hence all languages share the same universal grammar and underlying concepts.

Deutscher argues that cultural differences are reflected in language in profound ways.

Colors exist in a continuum, so when does blue become green? If two people have different languages in which color description is divided up in varying ways, will they experience the world differently?

Glasdstone - Studies on Homer and the Homeric Age (1858) - paucity of Homer’s color vocabulary, and the fact that blue was almost entirely absent. Black had 200 mentions, white 100, red fewer than 15, and yellow and green fewer than 10 each. Nothing was described as blue.

Philologist Lazarus Geiger looked at other cultures and found no reference to blue—not even in describing the sky. The only exception was Egypt, which by coincidence was the sole culture able to produce a dye colored blue.

SAPIR AND WHORF

The most famous version of linguistic relativity is the Sapir-Whorf hypothesis, named for linguist Edward Sapir and his student Benjamin Whorf. It states that the way we think is affected by the language we use, and someone with a different language will think and see the world differently. Each language represents reality differently, so we all perceive reality differently.

TASTING NOTES: THE TURNING POINT

Work done by the enology department of the University of California, Davis, in the 1970s and 1980s

In 1976, Maynard Amerine and Edward Roessler published a manual for the sensory evaluation of wines. Their goal was to replace vague and fanciful wine terms with a set of more precise words, shifting from the likes of “masculine,” “naive,” “harmonious,” and “presumptuous” to a standardized vocabulary that was more analytic in nature.

This led to the wine aroma wheel, by Ann Noble. This was a major step forward in pushing “winespeak” in a more scientific, rigorous direction

THE FLAVOR OF WINE

RECONSTITUTIONEXPERIMENTS

LIKING AND IDENTIFYING

OUR TASTES ARE ADAPTABLE

MERE EXPOSURE

Sylvain Delplanque and colleagues (2015)

Gave participants several odors, and asked them to rate each odor’s pleasantness, intensity, and familiarity.

Neutral and mildly pleasant odors showed an increase in pleasantness ratings

Unpleasant and very pleasant odors remained unaffected by frequency of exposure

John Prescott and colleagues – attention matters for mere exposure for odor

Identification task: different smells were chosen either to be targets (the team would draw the subjects’ attention to them) or nontargets (the subjects’ attention was not drawn to them)

Mere exposure works only when we pay attention (eg experts’ wine vocaublary)

LEARNING TO LIKE

“When I was a novice taster, I tasted lots of great white Burgundies and thought this was the epitome of white wine. I remember reading about Condrieu as one of the world’s great white wines. So I rush out, buy this expensive Condrieu, put it in the fridge, get ready: I am very excited. And I open it up and I do not really like it. I was surprised. I thought: why do people like this? I was disappointed in me as much as in anything else. Then I was talking to someone a little more experienced in wine. They said: don’t you love that bitter apricot kernel flavor? Don’t you like the oiliness of it? I suddenly went back in my mind and thought that is exactly what it tasted of. It was oily and fatty and had this bitter apricot character. I thought: that is right. They said: it is really good with salty seafood. I suddenly could put all those things together in my mind. Without changing how I remember it tasting, I thought: I want to try that again. Now thinking of it, with those descriptions and with that way of articulating and expecting it to be like that, I loved it. Now it is one of my favorites.”

SMALL SHIFTS IN OUR RESPONSES CAN HAVE TELLING RESULTSMatthew Kieran, Professor of Philosophy and the Arts at the University of Leeds:

“Small refinements in the same discriminatory capacities and responses can radically affect our experience and appreciation of art works [and wine, equally] in ways we are all familiar with. I once thought of the work of Mondrian’s late to middle period as good graphic design, nice but flat arrangements of line and color, and was puzzled as to why people thought his work particularly valuable as art. Yet once I was able to see some of these pictures as representing abstracted projections of pictorial space the structure of my experience was transformed and my evaluation inverted radically from thinking them no good to rating them pretty highly.”

DAVID HUME, ON THE IDEAL CRITIC

“One person is more pleased with the sublime; another with the tender; a third with raillery. One has a strong sensibility to blemishes, and is extremely studious of correctness: Another has a more lively feeling of beauties, and pardons twenty absurdities and defects for one elevated or pathetic stroke. The ear of this man is entirely turned towards conciseness and energy; that man is delighted with a copious, rich, and harmonious expression . . . Comedy, tragedy, satire, odes, have each its partisans, who prefer that particular species of writing to all others. It is plainly an error in a critic, to confine his approbation to one species or style of writing, and condemn all the rest. But it is almost impossible not to feel a predilection for that which suits our particular turn and disposition. Such preferences are innocent and unavoidable, and can never reasonably be the object of dispute, because there is no standard, by which they can be decided.”

BRINGING IT ALL TOGETHER

How should we approach wine tasting?

Any assessment or rating of a wine is a personal experience: we bring a lot to the tasting experience

Our perception is something we have created based on the chemical properties of the wine

Any score or assessment is a property of our interaction with the wine, and does not belong to the wine

Learning together brings our perceptions closer together

Our perception changes with experience

IMPLICATIONS

Multimodal perception of wine shows us that wine isn’t just about taste and smell

The stuff around wine matters a great deal

It doesn’t just influence our liking: it is part of the perception itself

The wine is a whole, and we should make better use of global descriptors