The three positive attributes of oil, the ones that must be present in a true extra virgin, are fruity, bitter and pungent.
An oil is more prized the more it displays a [b]fruity[/b] aroma, i.e. an olfactory-gustatory plant sensation that can recall healthy, fresh olives picked at the right degree of ripeness, green grass, tomato, artichoke, aromatic herbs. It is a pleasant sensation, which can be more or less “green” or “ripe”.
[b]Bitter[/b] is the basic taste characteristic of oil obtained from green or turning-colour olives. If you try chewing an olive just picked from the tree, you immediately perceive an intense bitter sensation: it is therefore reasonable to expect that [b]extra virgin oil[/b], by definition extracted only by mechanical means from olives, should be [b]at least somewhat bitter[/b]. [b]Pungent[/b] is the sharp tactile sensation characteristic of oils produced at the start of the olive season, mainly from still-green olives, perceived in the throat.The presence of bitter and pungent is proof of the presence in the oil of [b]natural antioxidants beneficial to our health[/b], so it is very important that extra virgin oils be bitter and pungent (to a variable degree depending on cultivar, extraction method and freshness).
Unpleasant sensations, i.e. defects, that can be found in an oil are numerous, and there is a common vocabulary used by all tasters to describe them. The main defects are:
– [B]fusty (heated)[/b]: sweetish, putrid sensation due to anaerobic fermentation of olives piled up for a long time before processing;
– [B]mouldy-humid[/b]: flavour that comes from olives picked up off the ground that have reacted with micro-organisms such as fungi and yeasts and/or that have been stored for days in humid environments;
– [B]fusty sediment (“morchia”)[/b]: the oil acquires this defect if it is not filtered well and remains for a long time in contact with the sediment (bottom sludge);
– [B]winey-vinegary[/b]: hint of wine or vinegar due to aerobic fermentation of the olives;
– [B]metallic[/b]: defect of oil that has been in contact for a long time with unsuitable metal surfaces;
– [B]rancid[/b]: due to an oxidative process caused by poor storage;
– [B]vegetation water[/b]: defect caused by contact of the oil with vegetation water;
– [B]earthy[/b]: defect deriving from olives picked with earth on them, or muddy and unwashed;
– [B]grubby[/b]: typical of oils obtained from olives heavily attacked by the olive fly;
– [B]hay-wood[/b]: characteristic odour of oils coming from dried olives.
