The touch of wine: what is that?
If during a tasting you are told about touching wine, make no mistake: it is not a question of dipping your fingers in your glass to judge its roughness directly by hand. We are talking here about touching with the mouth. In fact, the oral apparatus concentrates almost a quarter of the tactile sensors present on the human body (yes!), and this is what allows us to feel and appreciate the texture of the foods we eat. eats and drinks we drink.
For wine tasting, it's the same thing: the taste of wine is not only confined to its flavors and aromas but also takes on a whole tactile dimension. Let us guide you through this often underestimated and yet oh so important part of tasting.
The tongue loosens
There are tactile taste buds on the tongue, in addition to the well-known taste buds that identify sweet, salty, sour, bitter and umami. Rather concentrated at the front of the tongue, these taste buds are receptors that allow us to understand the geometry (i.e. the shape) of foods or drinks, their texture and their consistency. There are thus five types of receptors which react to different stimuli according to their function and are generally activated by movement of the tongue: touch is an active sense unlike taste.
This is why it is important to move your tongue when tasting a wine, to understand all of its tactile qualities, and not just the aromas and flavors. The thief lover of wine can then indulge in full awareness in tasting the haptic properties of his bottle (or better, of his flask).
Surface textures: vibration receptors
First, let's focus on appreciating the surface of the wine by placing the tongue against the palate and just letting the liquid pass through to assess its surface qualities: is it smooth, is it rough? What material does it remind me of to the touch: silk, velvet, canvas? Does it cause a feeling of dryness?
Certain taste buds identify the texture of the wine by the amplitude and frequency of the vibrations generated by contact between the tongue and the liquid. For example, we will say of a wine that it is silky if it is soft to the touch of the tongue, if the tannins seem to slide smoothly over the mucous membranes, reminiscent of the very fine mesh of silk causing little friction. Conversely, we will say that a wine is rough if the tannins give the impression of rubbing as if their surface were grainy: this is the sensation of harshness, generally linked to youth and immaturity. tannins.
Structure and consistency: pressure receptors
Then, we lower the tongue to the middle of the mouth to make the wine move and appreciate its weight, its density and its fluidity. The goal here is no longer to understand the surface but the depth of the wine: how is it structured? What does its consistency remind me or evoke?
The tongue is a muscle and you have to use it: by exerting pressure, these sensors allow you to understand the consistency of the wine. We can thus evaluate its viscosity: a sweet white will be thicker, more viscous than a dry white . Likewise, some red wines seem thick on the palate, denser, or even heavier. These are the receptors that transmit this information to us.
Geometry and conformation
Talking about the geometry of wine may seem a little absurd given that a liquid takes the shape of its container and yet we are preparing to do so. Some will prefer the term conformation which better evokes the way in which the wine settles in the mouth. We actually evaluate the spreading or tightening of the liquid which depends largely on how it reacts to saliva.
Some even talk about horizontal or vertical wines (kezako?). This is obviously an image to distinguish a wine which lines the entire mouth (which will be horizontal) from a wine which reacts with saliva in such a way that a cushion of drool forms and envelops the sides of the mouth. mouth. The wine then finds itself tightened in the center of the tongue and in this way it is “vertical”.
Obviously many geometric terms will rather have a metaphorical dimension of evocation. The classic round wine is not really round, we agree, but is a pleasant wine on the palate, low in acidity and low in tannin. We talk about roundness because it evokes the satisfaction of a wine which perfectly fits and coats the mouth without causing contraction of the taste buds... But look, is this a perfect transition?
Astringency: deformation receptors
Upon contact with certain substances, the mucous membranes tend to contract or expand and the sensation of contraction is particularly noticeable. Some like it, others hate it: it is the tactile effects of acidity or bitterness, for example, which act on both taste and haptic taste buds. This effect is well known under the term astringency, a notorious property of tannins which have a strong effect on tightening the mucous membranes.
Astringency therefore has little to do with taste and much more to do with touch. To evaluate the tannins of a red wine, it is important to keep the liquid in the mouth for a long time: their effect only appears several seconds after contact with the mucous membranes. For what ? Because the astringent effect of tannins is the result of an aggregation between them and certain proteins in saliva. Thus the time and the degree of salivation greatly influence the tasting and appreciation of a wine depending on the individual. If you produce a lot of saliva, you will perceive the tannic subtleties of a wine much better than the unfortunate person with a dry mouth.
Aging also has its importance: over the years the tannins depolymerize due to oxidation and therefore aggregate less, which basically means that by breathing too much, they simply lose their arms to grip saliva proteins. who catch their eye ( not for scientific purposes ). They then give the impression of being more pleasant, rounder in the mouth. They actually lose their astringency and gain subtlety.
Heat and tingling
Thermal receptors
The temperature of the wine is obviously perceived by the taste buds, which is why we estimate ideal tasting temperatures according to the qualities of the wines. But beyond the real thermal sensation, there is a thermal illusion captured by these receptors: this is particularly the case of the sensation of heating caused by ethanol (particularly in spirits) or very spicy wines. The opposite case also exists with, for example, menthol or eucalyptol which give an impression of freshness in the mouth.
Irritation receptors
We sometimes feel a spicy side in the wine: another tactile sensation that is well known to chili lovers. So spiced wines or spicy spirits (like a rum flavored with chili) will have this irritating effect on the mucous membranes. But it's not just a matter of jalapeño, carbon dioxide also activates these receptors (at a lower dose, of course) and this irritation can be felt when tasting sparkling wines.
