GENETICS: How Inherited Taste Sabotages Recommendations

See also this update: Genetic science shows why wine reviews and taste profiles miss the target for recommendations


Some people hate the taste of raw tomatoes.

Others get positively hostile if you try to feed them cilantro.

Broccoli bashers abound.

Liquorice loathers understandably shy away from foods seasoned with fennel and anise seed.

What does this have to do with wine preferences?

Only everything.

INDIVIDUAL PREFERENCE VS. RATING

One of the things that keeps being missed by readers in my daily News Fetch featured wines is the fact that these selections are wines that I personally prefer. Other people may loathe the ones I love. Conversely, I cannot stand many wines that are highly rated by the critics.

For more reasons than we’ll discuss in this article, trying to find personally enjoyable wines by relying on experts and numerical ratings presents a fundamental barrier to consumer wine choice and purchasing.

Please don’t misinterpret this as a call to abolish critics, ratings and scales. Those serve useful, enjoyable and entertaining purposes for many people.

However, among the more valuable lessons that came from creating and testing the SavvyTaste Facebook App was that users were highly enthused by expressing wine preferences as opposed to ratings. I’ve withdrawn that app because the lessons have been learned and are being applied differently.

GOOD TASTE? TASTES GOOD.

Preference is simple: you like it or not. Rating, on the other hand, implies — but fails to establish — an objective, all-encompassing, quality judgement.

And while judgement serves professionals and enthusiasts well, it sends a very large part of the consumer market running for the beer and booze aisles.

To steal (and riff on) the old StarKist tuna slogan:

Consumers don’t want a wine with good taste, they want one that tastes good. (To them.)

Failing to satisfy that desire has probably hurt wine sales more than any other single factor.

GENES AND INDIVIDUAL TASTE PREFERENCES

Like most things in life, taste preferences result from both nature and nurture — and, often, the two working hand in hand.

The genetics of human taste complicates wine selection more than most people realize.

As anyone who has had a head cold knows, taste depends upon smell.

Smell, in turn depends upon tiny structures called Olfactory Receptors (OR). Of course, ORs, are formed because your genes direct their growth.

That’s the simple part. It gets complicated when you realize that every human has between 900 and 1,000 genes that code for Olfactory Receptors. This represents 3 to 5% of all genes in the human genome.

In the average person, this translates to roughly 350 different types of ORs.

What’s more, not everybody has the same number or even the same set of 350 receptors

COMPLICATION PILED UPON COMPLICATION

Things get more complicated.

Each Olfactory Receptor can be triggered by multiple smells (odorant molecules).

Plus, an odorant molecule can trigger multiple ORs.

In addition to the odor responses, each type of Olfactory Receptor can respond not only to the identity of the odor, but to its intensity as well.

Finally, there exists a huge range in people’s ability to detect odors. This is called the “Odor detection threshold.”

This means, for example, that the same types of olfactory receptors involved with the ability to detect the scent of almonds could vary widely from person to person. Some may miss the “almond notes” in the bouquet of a wine or have those notes diminished. And that could change their overall perception of fragrances they experience.

PROCESSING … PROCESSING …

All those olfactory signals and amplitudes must be carried to the brain by nerves which have been formed through individual genetics.

Then, at the brain end of the nerve, all those signals be collected and processed by a part of the brain which has been formed with its own gene variations.

Finally, all that triggering and signalling and processing must filter into conscious perception which is a product of genes, experience, culture and education.

Given all this, it becomes a miracle that any two of us can ever agree on what fruit it is that we think we smell in the bouquet of wine. And no wonder that we disagree so often.

TASTING COMBINATIONS

Taste buds and genes get piled on top of the hundreds different types of Olfactory Receptors. The genetics of taste bud research seems to lag behind the sense of smell.

Other than the agreement that we detect sweet, sour, bitter, salty, and umami I have had trouble finding out how many genes and receptors are responsible.

However, one study (see below), notes that there are 20 to 35 different genes that encode receptors for the bitter taste.

Again, individual genetics determines the mix, sensitivity and number of taste receptors.

The number of combinations and permutations of all the genetic variations in both taste and smell can number into the billions or trillions. It is likely that no two people experience the same wine exactly the same way.

DEVELOPMENT AND EXPERIENCE

One final totally non-linear complication to lay on top of all the unpredictables: science has found that what a mother eats and drinks during pregnancy can permanent affect the taste preferences of her child. Finally, life exposure to tastes can change preferences as well.

EDUCATION, CALIBRATION, EVALUATION …

Education can bring some order to this world sensory chaos.

By studying with experts who can teach students that a wine they are sampling is tannic or over-ripe, a calibration takes place. That calibration then becomes the basis for evaluation and rating.

This works well for experts and enthusiasts, but not so much in helping consumers find a bottle of wine they prefer.

… HOMOGENIZATION …

Wine education is necessarily calibrated against a standard derived from a lot of people who talk to and study with each other. As a result, they come to a consensus that certain wines have certain characteristics and balances they consider desirable.

But taste in wine tends toward style trends just like shoes, hemlines and fashion runways. Parkerization was a trend. So, too, the current reaction to Parker style in which many critics tout austere wines with little fruit at all. The same might be said for proponents of “natural” wine.

Each taste group calibrates among themselves and results in a homogenization of what is judged “good” or “bad.”

It is worth noting that professionals and experts themselves are often inconsistent and their ratings flawed: An Examination of Judge Reliability at a major U.S. Wine Competition

… PERCEPTION

Education, calibration, evaluation and homogenization all neglect the central point of this exercise: perception.

Perception is rooted deeply in consciousness. Take an example from daily life and physics: any group of people can look at a swatch of red cloth and (unless someone is color-blind) agree that the color is red. A physicist can measure that particular color of red and produce an absolute determination that it is of a given frequency and wavelength.

But no one can determine whether the group members are experiencing — perceiving — the color the same way. Most likely they are not.

Unlike the frequency of a particular red, there is no absolute objective measure of “bitter” or “sweet.” No absolute “tastes good!”

No absolute “tastes bad!” Just individual perceptions.

Tomato, cilantro, broccoli, liquorice, almond.

It’s true that expert recommendations can often be a rough starting map toward finding one’s taste preferences — but only if one’s genetic makeup, culture, development and education are sufficiently similar to the expert’s.

Because experts have calibrated themselves within a narrowly grouped subset of taste, consumers who are not so related will often find the recommendations frustrating and useless.

EMBARRASSMENT & REVELATION

The consumer feedback from SavvyTaste revealed a lot of people who were embarrassed to admit that they preferred Cupcake Cabernet to a Bordeaux first growth.

During its operation as an experimental tasting system, SavvyTaste did succeed in connecting a number of people who preferred Cupcake Cabernet to a Bordeaux first growth. They then shared other recommendations.

Those people who shared a taste for Cupcake Cabernet (and could get over the social embarrassment of admitting it online) often discovered that while they agreed on Cabernet choices, their individual taste preferences diverged when it came to whites or other red varietals.

Tomato, cilantro, broccoli, liquorice, almond.

PERSONAL PREFERENCE RULES … SYSTEM NEEDED

Personal preference rules. What is needed is a way for them to become an efficient wine recommendation system. This series of posts will conclude with how that can be done.


Further reading:

Molecular Genetics: “The sense of smell: genomics of vertebrate odorant receptors

Journal of Cell BiologyThe cell biology of taste

Why We Like What We Like

<a href=”https://www.livescience.com/10457-smell.html”>How We Smell</a>

<a href=”https://academic.oup.com/chemse/article/42/3/177/2992865″>Simplifying the Odor Landscape</a>