Wine Q&A – Part 2
Q: Why are some wines not suitable for vegetarians?
Normally this is because of the agents that have been used to ‘fine’ or clarify the wine, which can be animal derived products like isinglass (from fish) or gelatin (which can be derived from animal bones). There are alternative fining agents like PVPP, a synthetic agent, and Casein which is made from milk (so not suitable for vegans). Vegetarian-suitable wines normally carry that information on the back label.
Q: What kind of wines improve with age?
This is a big topic. Generally, only more expensive wines will age successfully: most wines costing less than £10 are made for short-term cellaring only. But this does not mean that all expensive wines are guaranteed to improve with age: that depends on many factors including the grape variety, the region where the wine was made, the style of wine, and crucially, how well it is stored. Traditionally, Cabernet Sauvignon-based wines from Bordeaux have improved with cellaring – the tannins have softened and the wines have become increasingly harmonious. Other Cabernet Sauvignon wines from elsewhere can be long-lived too, but sometimes wines made from much riper grapes in hotter climates, without the same levels of tannin and acidity, age a little less well for example.
Q: What makes a wine sweet?
There are a variety of methods for making sweet wines. These vary from cheap and easy (stopping fermentation with some sugar remaining and topping up with sweet grape juice), to some of the most labour intensive and expensive processes in the wine making world. At the other end of the scale, Botrytis cinerea, or ‘Noble rot’, is a fungus which can attacks grapes leaving the grapes shrivelled and unsightly, but tasting deliciously sweet and rich. Some of the world’s greatest sweet wines including Sauternes from France and Trockenbeerenauslese from Germany are made with these grapes. Late harvest wines are made from grapes left on the vine long after they are ripe, the sweetness building into the late autumn. Icewines are an extreme form of late harvest, the grapes left on the vine into winter until they freeze. When crushed, the water content is dispelled as ice leaving a thick, lusciously sweet wine. Fortifying with spirit is another way to produce a sweet wine: fermentation converts sweet grape juice into dry wine by converting sugar to alcohol. But if you add spirit half way through, the fermentation stops, leaving lots of sugar behind. This is how sweet wines like Port, Rivesaltes and Australia’s liquor Muscats are made.
Q: How do you make rosé?
In Champagne it is allowed to mix some red wine with the white Champagne, but for almost all table wines rosé is just a light red wine: red wines take their colour from the skins of dark grapes during pressing and fermentation – the dark pigment is in the skins, not the grape juice. If you remove the skins from the press or fermentation tank after a short time and continue to ferment without them, then only a little colour is leached and the wine has many of the properties of a white wine. That’s rosé.
Q: What is the difference between Vin de Pays and Appellation Controlée?
Another big topic, but basically these are two French systems for classifying and controlling wine production. Traditionally Appellation Controlée (AC) was for the best quality wines of specified regions, and wine would only qualify if following strict rules imposed by the AC authorities. Many winemakers wanted to experiment, growing different grapes or making wines with different methods, which gave rise to a new geographical control and classification called Vin de Pays, which was more flexible. Though seen as a ‘lesser’ classification, VdP wines can be of very high quality and can be expensive. Recently, it has been annouced that Vin de Pays is being replaced with Indication Geographique Protégée (IGP).
Q: Why do some wines give me a headache?
Clearly higher alcohol wines can be the source of this problem, but some people have a sensitivity to sulphur in wines, and yet others to histamines, which can be found in red wines in particular.
Q: What does “corked” mean?
Not that there are little pieces of cork floating in the wine, but that the wine has been affected by a chemical called TCA (2,4,6-trichloroanisole). TCA can be created in a wine if there is a mould present on the oak tree bark used to make the cork, and can be detected as a musty smell and off-flavours. Many producers have switched to screw-caps and other synthetic closures mainly because of this problem.
Q: What country produces the best value wines?
This is very difficult to say and depends a lot on interpretation. Quality-to-price ratio is all important: cheap doesn’t necessarily mean good value, and some would argue that cheap wines are rarely good value. Certainly the lower cost of land and production in countries like South Africa, Argentina and Central European countries results in less expensive wines, but then the huge, automated wineries of Australia and California or the modern facilities in France’s Languedoc or Spain’s La Mancha allow them to compete head on too.
Q: How much wine constitutes a ‘unit’ of alcohol?
It’s a common misconception that one glass of wine equals one ‘unit’. The unit in which alcohol is measured for those advocating healthy consumption is actually 10 millilitres of pure alcohol. So to work out how many units are in a glass requires you to know how much alcohol is in the wine, and how much wine is in the glass. For example, a ‘large glass’ is commonly 250 millilitres. If it is a wine with 14% alcohol, it actually contains 3.5 units, not one: the formula is millilitres of liquid (250) x alcohol (14) divided by 1000.