Wine Faults and Flaws. Keith Grainger
we have spat out the wine, and this action will help determine the ‘finish’ of the wine.
As we taste, chew, and dissect the wine in the mouth, before finally spitting, numerous sensations develop. This evolution is considered in stages. The initial attack is the sensation as the wine taken into the mouth. This is followed by the development on the palate where we perceive the flavour characteristics and intensity, and then the finish which comprises the final impressions of the wine including the balance. The length is a measurement of how long the sensations of the finish and aftertaste last. Tasters sometimes refer to the progressive sensations as ‘front‐palate’, ‘mid‐palate’, and ‘back‐palate’.
When assessing the palate of wine, we may consider the following headings:
Dryness/Sweetness;
Acidity;
Tannin;
Alcohol;
Body;
Flavour intensity;
Flavour characteristics;
Other observations;
Finish.
Faults that are or may be detectable on the palate are shown in Table 2.5. This list is not exhaustive.
Table 2.5 Faults detectable on palate of wine.
| Retro‐nasal, gustatory or trigeminal indicator | Possible fault | Refer to: |
|---|---|---|
| Musty, damp sack, wet cardboard | Chloroanisoles and Bromoanisoles | Chapter 3 |
| BAND‐AID® stables, animal, spicy | Brettanomyces (Dekkera) related faults | Chapter 4 |
| Burnt, bitter, dried‐out | Oxidation | Chapter 5 |
| Rotten egg, garlic, cooked cabbage, skunk | Excessive sulfur dioxide, volatile sulfur compounds, reduced aromas | Chapter 6 |
| Marmite (Vegemite), wet wool, wet cardboard | Light strike | Chapter 6 |
| Vinegar, nail varnish, solvent | Excessive volatile acidity, ethyl acetate | Chapter 7 |
| Thin body, metallic, non‐tannic bitter finish | Atypical ageing | Chapter 8 |
| Vomit | Lactic acid bacteria associated faults, (including mousiness) | Chapter 11 |
| Bacon, smoky bacon crisps | Smoke taint | Chapter 12 |
| Peanut, earthy, bell pepper (unexpected) | Ladybug (Coccinellidae) taint Brown marmorated stink bug (Halyomorpha halys) taint | Chapter 13 |
| Prunes, burnt, overcooked fruitcake | Heat damage | Chapter 14 |
2.7.2 Sweetness/Bitterness/Acidity/Saltiness/Umami/Trigeminal Sensations
Although highly sensitive, the receptors of taste buds can only detect five basic tastes: sweetness, bitterness, saltiness, acidity, and umami (the savoury taste of some amino acids). These are the non‐volatile compounds present in wine (although acetic acid is volatile). The fifth basic taste, umami, has only been recognised in the western world in 1985 and has only appeared in wine tasting notes in very recent years. There are claims of a sixth basic taste, the bitter, chalky taste of calcium, and other basic ‘tastes’, but such claims remain highly controversial. Trigeminal sensations, i.e. those detected by the trigeminal nerve, have recently come to be regarded in some quarters as yet another basic ‘taste’. However, these are not ‘tastes’, but sensations, e.g. the cooling effect of menthol/mint, or astringency. Of the five basic tastes, saltiness (comprising mainly sodium chloride) is usually not important in wine. The sensory cells of the tongue convert the detected tastes into electrical signals and send them to the brain's taste cortex. Until the late twentieth century, it was generally accepted that different parts of the tongue detect these basic tastes, and many wine‐tasting books and human biology texts still illustrate a diagram of the tongue detailing these areas. However, this concept has been discredited, largely by the work of Linda Bartoshuk when at UC Davis. For this chapter, I will rely on the approach that defined areas of the tongue are more sensitive to the individual basic tastes. It is not disputed that the ‘traditional’ areas of detection identify the tastes, only that the other areas do not. It is also accepted that the centre part of the tongue is considerably less sensitive to the basic tastes. There are tactile sensations of the wine that are also detected in the mouth, on the cheeks, teeth, and gums. These include tannin, body and alcohol, and the trigeminal sensations.
2.7.3 Dryness/Sweetness
Before discussing perceptions of sweetness, it is pertinent to visit the topic of grape sugars briefly. Grapes contain glucose (grape sugar) and fructose (fruit sugar) which will be completely or partially converted by the action of yeasts to ethanol and carbon dioxide during the fermentation process. If there is insufficient natural sugar in grapes to produce a balanced wine with the required alcoholic degree, in some countries the winemaker may add sucrose to the must, a process generally known as must enrichment or chaptalisation. There can be no doubt that the process reduces a wine's concentration. In theory, any added sucrose should be fermented to dryness. The purpose of chaptalisation is not to produce wines with sweetness. However, in practice, most fermentations cease before total dryness, as discussed below. At the time of writing, chaptalisation remains permitted in the more northerly zones of the European Union (EU), and incredibly is sometimes undertaken even in ‘good’ years when grape ripeness should not be a problem. For example, 2016 is generally regarded as an excellent year in Bordeaux, but chaptalisation of vats of Cabernet Sauvignon, Cabernet Franc, and Petit Verdot was permitted, and undertaken, in many districts. An alternative to chaptalisation is the addition of concentrated grape must which is comprised largely of glucose and fructose.
Sweetness, if any, in a wine will be particularly detected on the tip of the tongue. It is important to remember than we cannot smell sweetness (sugar is not volatile), although the nose of some wines may lead us to expect that they will taste sweet. This may or may not be the case. For example, a wine made from one of the families of Muscat varieties may have a fragrant and aromatic nose reminiscent of sweet table grapes, but the wine may be bone dry when tasted. Other characteristics can also give an illusion of sweetness, in particular, high‐alcohol levels (although sometimes too much alcohol can lead to a bitter taste), and vanillin oak. Thus, a high‐alcohol wine that has undergone oak treatment can mislead the taster into perceiving that it is sweeter than the actual level of residual sugar. Pinching the nose whilst rolling the wine over the tip of the tongue can help the novice overcome any distortions that the nose may be giving. However, the acidity of the wine also impacts on the taster's perception of sweetness. The higher the acidity, the less sweet a wine containing residual sugar may appear to be.
Thresholds