Κυριακή, 25 Ιουλίου 2010

Aroma & Flavour

Two basic organoleptic features, aroma and flavour, are the most important criteria for evaluating olive oil. Organoleptic control is achieved by specialized tasters according to the rules and standards determined by the International Olive Oil Council. Thirty minutes prior to tasting, these people are forbidden to smoke or use any perfume, deodorant, or even soap substances that may affect their final judgment. An hour before tasting, it is also forbidden to taste any food, and they cannot participate in the tasting process if they are taking any medication, have a cold, or are under psychological stress.

AROMA: Like wine, olive oil has a significant number of flavour and aromatic constituents. The natural aroma and flavour depends on the quality of the oil as well as the olive tree variety, the climatic and terrain conditions under which it grew, and the ripeness of the fruit. The greatest concentration of olive oil aromatic constituents is achieved during the period when the fruit changes from vivid green to slightly violet, heading towards black. Some of the aromatic constituents include aldeydes, carbohydrates, and aliphatic alcohols.

Flavours and aromas

Amending regulation 2568/91 of the EEC applies to all olive oil producing countries. This regulation helps us learn the wealth of flavours and aromas the different types of olive oil present.

Organoleptic valuation of virgin olive oil

* Olive ripeness: the smell and flavour of healthy and fresh olives, which have been gathered at the ripening stage
* Ripe: taste of olive oil produced from ripe olives, mostly without smell and with sugary flavour
* Unripe: taste of olive oil produced from unripe olives

Pleasant flavours and aromas

Gutierrez (1977) defines the following substances in olive oil that give it a special aroma and flavour:

APPLE: flavour that reminds one of apples

SWEET FLAVOUR: pleasant, not sugary

GRASS: reminds one of the smell of freshly cut grass

GREEN LEAVES: bitter flavour resulting from unripe olives ground with leaves and twigs

BITTERNESS: flavour produced from unripe olives or olives that have just started ripening; may probably be pleasant according to how intensely perceptible it is

ACRIDNESS: distinct sensation produced by certain olive oils that leaves a slightly acrid taste in the mouth

PUNGENCY: taste sensation of olive oils produced in the beginning of the producing season from mainly unripe olives; results from phenolic substances on the trigeminal nerve, which expand in the oral cavity

ALMOND: fresh or dried almond taste; can also indicate rancidity; results from sweet olives characterized by faint smell

FLAT or FAINT (musty): creates a faint impression; musty aromatic constituents

HAY: distinctive smell of certain olive oils that reminds one of grass

LEMON: flavour that characterizes few olive oils and gives the mouth the sour sharpness of citrus fruits

SORREL: a faint sour flavour of olive oils cultivated near lemon and orange orchards

PEPPER: distinctive piquant flavour of certain olive oils; sharp aroma

Unpleasant flavours and aromas

Oils with these characteristics are considered of low or poor quality:

RUSH: distinctive flavour produced from olives stacked in new bags made of fresh or dry rush

EARTH: distinctive flavour produced from olives gathered with earth or mud; may be combined with mould

MOULDY: distinctive flavour of olive oil kept too long in storage containers

WORM: distinctive flavour produced from olives severely affected by the chrysalides of “dakos”

METAL: distinctive flavour of olive oil that has been in contact with metallic surfaces for a long time

MILDEW: distinctive flavour of produced from olives that have become mouldy after prolonged exposure to dampness

RANCID: unpleasant flavour that indicates oxidization

MUSTY SMELL: distinctive flavour produced from advanced fermentation

BRINE: distinctive flavour produced from olives preserved in salt solutions

CUCUMBER: flavour that results from prolonged airtight storage, mainly in tin containers, or oils overheated during production

COOKED or BURNED: distinctive flavour of olive oils that have been overheated during crushing

DREGGISH: flavour resulting from storage in containers that have not been cleaned well after previous use

LUBRICANTS: unpleasant smell resulting from inadequate cleaning of extracting equipment

WALNUTS: unpleasant smell that reminds one of stale dried fruit