The International Olive Council (IOC) has developed a system for the objective organoleptic (tasting) assessment of olive oil in order to determine an oil’s quality and commercial trade value. This assessment method is based on panels of trained tasters recognizing the absence and/or presence of specific positive and negative (defective) attributes.
Desirable traits
- Apple/Green Apple: indicative of certain olive varietals
- Almond: nutty (fresh not oxidized)
- Artichoke: green flavour
- Astringent: puckering sensation in mouth created by tannins; often associated with bitter, robust oils
- Banana: ripe and unripe banana fruit
- Bitter: considered a positive attribute because it is indicative of fresh olive fruit
- Buttery: creamy, smooth sensation on palate
- Eucalyptus: aroma of specific olive varietals
- Floral: perfume/aroma of flowers
- Forest: fresh aroma reminiscent of forest floor, NOT dirty
- Fresh: good aroma, fruity, not oxidised
- Fruity: refers to the aroma of fresh olive fruit, which is perceived through the nostrils and retro-nasally when the oil is in one’s mouth.
- Grass: the aroma of fresh-cut (mowed) grass
- Green/Greenly: aroma/flavour of unripe olives
- Green Tea: characteristic of some unripe olive varieties
- Harmonious: balance among the oil’s characteristics with none overpowering the others
- Hay/Straw: dried grass flavour
- Herbaceous: unripe olive fruit reminiscent of fresh green herbs
- Melon: indicative of certain olive varietals
- Mint: indicative of certain olive varietals
- Pear: indicative of certain olive varietals
- Peach: indicative of certain olive varietals
- Peppery: stinging sensation in the throat which can force a cough (see pungent)
- Pungent: stinging sensation in the throat which can force a cough (see peppery)
- Ripely: aroma/flavour of ripe olive fruit
- Round/Rotund: a balanced, mouth-filling sensation of harmonious flavours
- Spice: aroma/flavour of seasonings such as cinnamon, allspice (but not herbs or pepper)
- Sweet: characteristic of mild oils
- Tomato/Tomato Leaf: indicative of certain olive varietals
- Tropical: indicative of ripe olive fruit with nuances of melon, mango, and coconut
- Walnut/Walnut Shell: nutty (fresh not oxidised)
- Wheatgrass: strong flavour of some green olive fruit
- Woody: indicative of olive varietals with large pits
Undesirable traits
- Acetone: aroma of nail polish remover, associated with winey defect
- Blue Cheese: aroma associated with muddy sediment defect
- Brine: salty taste indicating that oil was made from brined olives
- Bacon: smoky essence that may indicate oxidation
- Burnt/Heated: caused by processing at too high a temperature
- Cucumber: off flavour from prolonged storage, particularly in tin
- Dirty: oils which have absorbed unpleasant odours and flavours of dirty waste water during milling
- Dreggish: odour of warm lubricating oil caused by the poor execution of the decanting process
- Esparto: refers to straw-like material in mats occasionally used in older mills that may create a hemp-like flavour in oil
- Fiscolo: refers to coconut fibers in mats occasionally used in older mills that may create a hemp-like flavour in oil
- Flat/Bland: oils which have no positive or negative aroma or flavor characteristic of olive oil; may indicate presence of refined olive oil
- Frozen/Wet Wood: sweet, dry, and untypical aroma/flavor derived from olives which have been exposed to freezing temperatures
- Fusty: anaerobic fermentation that occurs when olives are stored in piles too long before milling
- Greasy: flavour of diesel or gasoline caused by equipment problems
- Grubby: flavour imparted to oil by olive fly damage to olives
- Hay-wood: flavour of dried olives
- Muddy Sediment: barnyard-like aroma caused by olives’ prolonged contact with dirt before or after milling
- Musty: mouldy, humid flavour created by wet olives that have been stored too long before pressing
- Metallic: oils that have had prolonged contact with reactive metal surfaces either during processing or storage
- Rancid: the flavour of oxidation that occurs as the oil ages, often described as “stale nuts”
- Rough: pasty, thick, greasy mouth feel
- Sour Milk: aroma associated with muddy sediment defect
- Stale Nuts: flavour of oxidised oils, rancidity
- Unbalanced: oils with overwhelming flavours of bitterness and pungency
- Vegetable Water: oils that have been stored in contact with the water content of the olive after processing
- Winey: sour/vinegary flavour caused by aerobic fermentation of olives during processing
- Vinegary: sour/vinegary flavour caused by aerobic fermentation of olives during processing.
- Yeasty: aroma of bread dough; associated with winey defect
