The primary and only thing to remember about wine tasting and marking is that it is a very personal activity. It does not matter what others (even experts) think, it should reflect your views on what you think about the wine. However there are some useful guidelines which should be followed and these are set out in the marking sheets issued to members and are amplified below.
There is no such thing as a correct score. The only thing that matters is how a particular wine rates for you. Wines are marked out of 100 points, an internationally agreed scale. The points are split up between Appearance (15), Nose/Aroma (40) and Taste (45). These are the maximum points you could award in each category and if you did that it would come to 100 and an absolutely perfect wine, which does not exist. So in each category you scale your points downwards, depending on how short of perfect the wine falls.
Appearance should only be marked down if the wine is cloudy, watery or of a colour that is unattractive to the taster, so generally if appearance is good you will give the wine between 15 and 12 points.
When awarding points for Nose/Aroma the taster should first smell the wine in the glass without moving it. Secondly the wine should be smoothly swilled in the glass, holding it firmly by the stem or base, releasing further aromas and flavours that may not have been initially evident. In this way the taster will appreciate the full potential aroma of the wine. It is highly unlikely that a wine would score the maximum , but an average score for an average wine could be expected to be around 30, or a bit more, much depending upon the taster’s personal preference. See how the wine runs down the side of the glass when you have swilled it. The more pronounced these legs, as they are called, are, the higher the alcohol level of the wine.
The mark for Taste is again a matter of personal preference, as described above. Use as markers wines that you as the taster have previously enjoyed. However, unless a wine is clearly deficient in flavour, body, or the balance between acidity and fruit, it should not be marked down harshly. Similarly, a wine that delights the taster with its complexity, depth of flavours, fruit and smooth tannins, should probably not be awarded the full 45 points, as perfection is unlikely to have been achieved. Depending on your view of the wine, a score of 42 to 31 is likely to be awarded. 30 or below means you have definitely found fault with the taste.
The main thing is that it all adds up to your own view of the wine tasted. You will eventually achieve your own personal view about wine and even without the aid of the above breakdown will rate a wine as 81,85, 89 points or more. If you decide to rate a wine as say 85 points and another that you feel has an edge on it at 89 do not waste your time trying to search for differences. You simply find one is better than the other and you could just as easily have given it 88 or 90.
Enjoy your tasting.