Wine Faults and Flaws. Keith Grainger
growing season or inadequate extraction. Full‐bodied and concentrated reds, especially those from hot climates, will be deep or opaque in youth, and this suggests intense flavours and may be indicative of good quality. The colour intensity of red wines decreases with maturity, but the opposite is the case with aged whites. However, occasionally extremely deep‐coloured red wines can be surprisingly lacking in flavours. There are a few red varieties that have coloured flesh as well as black skins (e.g. Alicante Bouschet) but are surprisingly lightly flavoured. These teinturier grapes may, very occasionally, be used in a blend to deepen the colour of a wine that might be perceived as too pale.
Further, intense colours can sometimes indicate winemaking methods that have focused on colour, rather than flavour, extraction. Mindful of the association in the eyes of drinkers (and critics) of deep red wines and perceived high‐quality, winemakers can manipulate intensity, for example, by the addition of 8000 color or Mega Purple, concentrates made from grape skins and seeds. Thus, the taster is cautioned against drawing conclusions as to style or quality at this stage. However, a red wine that is paler than expected or white wine deeper than expected may be suffering from oxidation, which will be further evidenced by the colour, nose, and palate.
2.5.4 Colour
Many factors affect the actual colour of a wine, as well as its intensity. These include the climate and region of production, grape ripeness, the grape variety or blend of varieties, vinification techniques including any barrel ageing, and the wine's state of maturity.
2.5.4.1 White Wines
White wines can vary in colour from almost water clear to deep gold or even amber. Words used to describe colour might also include green, lemon, straw, and (almost always a signal of alarm) brown. Some white varieties such as Sauvignon Blanc generally produce wines at the green‐lemon end of the colour range. In contrast, others such as Gewürztraminer (which has a more heavily pigmented skin) usually give straw or gold colours. Whites from cooler climates often appear lemon‐green or lemon, and those from warmer areas may veer towards gold. Sweet wines such as Sauternes are usually gold, even in youth, and will deepen, perhaps even to copper with age. The colour of all whites will darken with time. The rate at which this takes place varies considerably depending on several factors, particularly pH and acidity (higher acidity slows down the process) and how well the bottle has been stored. Brown colours are certainly a warning sign of faults, either lightstrike or severe oxidation. Lightstrike, discussed in Chapter 6, is most likely in white wines that have been bottled in clear glass or pale glass and exposed to ultra‐violet light sources.
Of course, the taster will be aware that many wines made from white grapes are deliberately oxidised during the production process, e.g. Amontillado and Oloroso Sherries, and the tuilé and rancio wines from Rivesaltes in the Roussillon region of France. Oxidation, as a fault, is discussed in Chapter 5.
2.5.4.2 Rosé Wines
Of all wine types, rosé is the category that is made for visual appeal. Winemakers and marketing departments know that an attractive appearance is crucial to the drinker's perceptions of style and quality. The colour of rosé wines depends on several factors, particularly the production techniques, e.g. whether the colour is the result of skin contact in the press, a short maceration in the tank, or if the wine has been made by the saignée method. This technique involves draining juice from a vat of fermenting crushed red grapes before heavy colour extraction, perhaps after 6–24 hours or so. If the vat is bled after six hours the colour will usually be pale, whilst 24 hours will give a deeper coloured rosé, but the actual colour and intensity will depend on many factors, including climatic conditions and grape variety. There is a very wide range of possible colours and intensities for rosé wines from onion‐skin to pink or even orange. Any orange or brown tints should be regarded as a danger sign, indicating oxidation which even in its early stages will result in a loss of fruit, and bitterness on the palate.
2.5.4.3 Red Wines
Red wines can vary in colour from purple through ruby to mahogany. Purple is indicative of a young red wine, some being so intensely coloured that they appear almost to be blue‐purple. As the wine begins to age, the purple tones lighten to ruby, with further ageing to a warm brick red colour, and with full maturity possibly to garnet or even tawny. We may consider the colour of red wine on a scale that runs from purple, through ruby and garnet, to tawny. Red wines that have undergone lengthy barrel ageing, in which controlled oxygenation has been taking place, change colour and also lighten in intensity faster than those bottled early and aged in bottle. A good illustration of this is the contrast between a Vintage Port (not Late‐Bottled Vintage – LBV) of about 12 years old, following two years or so in vat, aged in bottle for 10 years and a 10‐Year‐Old Tawny Port, which has been matured in pipe (cask) and bottled when ready for drinking. This contrast is illustrated in Figure 2.4.
Figure 2.4 Vintage Port and Tawny Port.
A brown wine is tired, oxidised, and probably undrinkable. Red and white wines that are heavily oxidised are pretty much indistinguishable in colour.
2.5.4.4 The Rim and Core
The colour gradation from the heart or core of the wine to the rim, where it touches the glass should be noted. The greatest colour intensity is at the heart, but in the area approaching the rim, the colour is paler and different. For example, a wine that is ruby coloured at its core may gradate to brick red or garnet tones towards the rim, indicating maturity. As the rim of the wine touches the glass, the last millimetre or two will be water clear. The distance of the colour gradation will vary from just a couple of millimetres in a young wine to perhaps a centimetre or more in a mature example. Mature white wines too will have considerable gradation in colour approaching the final few millimetres of the rim, which again will be water clear. The colour of the rim should be observed (any hints of brown being a sign of possible oxidation), and the width of the rim noted, e.g. broad or narrow.
2.5.5 Other Observations
These may include, among other things, bubbles, petillance, legs/tears, and deposits.
2.5.5.1 Bubbles or Petillance
Bubbles are a key feature of sparkling wines, but a small amount may also be observed on still wines.
Still Wines
Occasionally, the presence of bubbles on a still wine could be indicative of a fault – either an alcoholic or malolactic fermentation (MLF) is taking place or has taken place in the bottle. This issue is discussed in Chapter 9. Cloudiness and/or presence of sludgy sediments might be a further indication of this. However, still wines in good condition may contain bubbles or petillance. Gases, namely carbon dioxide (CO2), nitrogen (N), and argon (Ar) may be used as a blanket at various stages of winemaking to prevent oxidation or other spoilage. Particularly if a very fresh style of wine is desired, it is common to flush the vats with one of these gasses. Bottles too may be pre‐evacuated of oxygen and gas sparged immediately before filling. Some of the gas (particularly CO2 which is highly soluble) may become dissolved in the wine – this does not generally detract from the quality, and can often add a sensation of freshness. Some wines, e.g. wines from the