Welcome to the fourth part of Tasting like a professional. We have looked at the method, at sight and at smell. Now the wine finally lands on the palate, and here the analysis becomes both more tangible and more demanding. For while the aroma can intoxicate us with its complexity, it is on the taste that the wine's architecture reveals itself: how the components carry one another, where the balance lies, and how long the impression lasts.
The important caveat first: much of what we call taste is in reality aroma perceived retronasally through the sense of smell. The tongue itself only registers the basic tastes. The rest comes from above, via the nose, while the wine is in your mouth. That distinction is crucial when you want to assess structure precisely and not confuse fruit aroma with sweetness, or oak with tannin.
What you will learn
- How to assess sweetness, acidity, tannin, alcohol and body individually
- What balance means in practice, and why the components affect how one another are perceived
- How finish and length are judged, and what they tell you about the wine
- Why most of what we call taste is actually aroma
The measurable components
The tongue perceives five basic tastes: sweet, sour, salty, bitter and umami. Umami is the meaty, broth-like taste linked to glutamates and certain amino acids. In the wine itself, however, it is primarily sweetness, acidity and bitterness (from phenols) that you can read on the palate. Salt and umami occur in some wines, but are subtle.
It is worth remembering that humans have relatively few taste receptors compared with the enormous repertoire of the sense of smell. We have around 2,000 taste buds, each built up of specialised cells, while the olfactory epithelium holds something on the order of five million olfactory neurons. This is why retronasal aroma is so dominant in our experience of taste. When you assess the structure, it is about consciously isolating what the tongue actually senses from what the nose delivers.
Sweetness
Sweetness in wine comes from residual sugar, that is to say glucose and fructose that has not been converted to alcohol during fermentation. Note that a ripe, fruit-driven wine can seem sweeter than it is. It is the aroma that fools you. Hold it dry and reserved against the front of the tongue and ask yourself whether there is actually sugar present, or whether the impression comes from ripe fruit aroma and glycerol, which gives fullness and a slight softness without being sugar.
Tannin, acidity and alcohol
These three are the wine's backbone, and they deserve to be assessed one by one before you judge the whole.
Acidity
Acidity is essential for the wine's life and freshness. Too much makes it sharp, too little makes it flat and dull. The most important organic acid in the grape is vinsyre (tartaric acid), followed by æblesyre (malic) and citronsyre. In cooler climates the grapes typically hold relatively more æblesyre in relation to vinsyre, while warmer climates give a different ratio. Malolactic fermentation converts the sharp æblesyre into the softer mælkesyre and thereby lowers the overall perceived acidity. When you taste, register the acidity as salivation along the sides of the tongue and as the wine's drive and spring. A wine without sufficient acidity falls apart, no matter how lovely the fruit is.
Tannin
Tannins are condensed phenolic polymers with a strong affinity for proteins, and it is precisely that affinity which creates the puckering, astringent grip in the mouth. They come from skins, stems and seeds, and catechin makes up the bulk of the grape's tannins. Assess tannin on two axes: quantity and quality. Does the grip feel rough and dry, or is it fine and ripe? Remember that alcohol affects the picture, because a higher alcohol concentration reduces the interaction between tannin and protein and can thereby make the tannins seem a little softer.
Alcohol
Alcohol in wine is ethanol, formed when yeast converts sugar. In table wines the level typically lies around the middle of the spectrum, while sweet and fortified wines lie higher. You sense alcohol as warmth at the back of the palate and in the throat, and it also contributes to the body's fullness. An important nuance: alcohol functions as a co-solvent together with water and helps draw out the wine's substances, but at very low concentrations volatile aroma compounds are released more easily. For the taster, this means that alcohol can both lift and mask aroma depending on the level. Burning warmth without corresponding substance is a sign of imbalance.
Body and balance
Body is the sensation of weight and fullness in the mouth, and it comes from the sum of dissolved substances: alcohol, glycerol, residual sugar and extract (proteins, tannins, minerals and more). Glycerol is in fact the most abundant compound in dry wine after water and ethanol, and it contributes noticeably to the round, slightly oily sensation without adding sweetness in the classic sense.
Balance is the central concept, and in practice it is a question of how the components carry and counter one another. Acidity balances sweetness. Tannin is balanced by fruit and alcohol. Alcohol is balanced by acidity and substance. No single component should stick out and dominate, unless the wine style specifically calls for it. A wine with high acidity can perfectly well be in balance, if there is sufficient fruit and substance to counter it. It is the relationship between the parts, not the absolute levels, that decides whether the wine holds together.
Here it is also relevant to remember the role of umami, even though it belongs in the food-and-wine context. Umami-rich dishes (aged cheese, charcuterie, mushrooms, tomato, shellfish) can make a wine taste more bitter, more tannic and more acidic, and at the same time blur fruit and sweetness. That illustrates the point about balance nicely: the perceived structure is not a fixed quantity, but something that shifts with context. The wine's own acidity, sweetness, salt or a touch of oak can counteract umami, while very tannic, oaked red wines are often a poor match for that kind of dish.
Finish and length
Finish is what remains once the wine is gone: the taste, the texture and the aroma that linger retronasally. Length is how long it lasts. Both are best judged by deliberately staying silent after spitting or swallowing and then counting how long a positive, coherent impression lasts.
Two things are worth separating. First, the length itself: a short finish disappears quickly, a long one lingers. Second, the quality of the finish: is it fruit and freshness that remains, or is it rough tannin, burning alcohol or a bitter aftertaste? A long finish is only a virtue if what lasts is pleasant and in keeping with the rest of the wine.
Note what dominates the aftertaste. Does the acidity stay and keep the wine fresh? Do the tannins tighten up at the last moment? Or does everything fade softly into a harmonious conclusion? The finish is often the most honest testimony to a wine's class, because it reveals whether the balance holds all the way, or whether something falls apart at the end.
In short
- The tongue only reads the basic tastes. In wine it is especially sweetness, acidity and bitterness. Most of what we call taste is aroma perceived via the nose.
- Assess sweetness, acidity, tannin and alcohol individually before you judge the whole, and be careful not to confuse ripe fruit aroma with actual sweetness.
- Body is the sum of dissolved substances, including glycerol, alcohol and extract.
- Balance is about the relationship between the components, not about their absolute levels.
- Finish is judged on both length and quality. A long finish only counts if what remains is good.
Frequently asked questions
How do I distinguish between sweetness and fruitiness?
Sweetness is residual sugar, which the tongue registers, typically towards the front. Fruitiness is aroma, which you perceive retronasally via the nose. A dry but very ripe wine can seem sweet because the intense fruit aroma tricks the brain. Try holding the wine in your mouth and focusing on whether there is actually a sugar sensation, or whether the impression disappears when you concentrate on the tongue itself.
Is a long finish always a sign of quality?
Length is often a good sign, but only if the impression is positive. A finish dominated by rough tannin, burning alcohol or bitterness is long in the wrong way. So always assess both how long and what lingers.
Ready for the next step?
You now have the tools to read a wine's structure, balance and finish. But what do you do when something is wrong? When the acidity tips over into vinegar, or when the bouquet takes on an unwanted sherry-like note from too much acetaldehyde? In the next part, Wine faults recognised in the glass, we look at how you identify the most common wine faults and what lies behind them.
Do take what you have learned out into practice and taste your way through a couple of bottles with a focus on the structure alone. And then remember that, for all the analysis, the best pairing is still the wine you like with the food you like. Drop by our selection when you want to put the theory to the test in your own glass.