Three senses are primarily used to identify olive oils: olfactory, which refers to one's sense of smell; gustatory, one's sense of taste; and tactile, perceptible to the sense of touch. The following positive and negative attributes have been defined by the International Olive Oil Council. It should be noted that what might be defined as a negative characteristic may be a treasured attribute in another region or culture.

Fruity - In general, the fruity attribute refers to the fruity characteristics of the olive. Olive fruitiness is generally a result of the degree of ripeness of the olives when they were milled. Unripe fruitiness will tend to have more of a grassy characteristic while ripe fruitiness will tend to be less aggressive. Smelling the oil and exhaling through the nose after tasting the oil will help you perceive an oil's fruitiness.

In addition to olive fruitiness, olive oils can also have flavors reminiscent of almond, citrus fruit (lemon, orange, bergamot, mandarin or grapefruit, exotic fruit (pineapple, banana, passion fruit, mango, papaya, etc.), fig leaves, green pepper herbs, olive leaf, pear, pine nuts, soft fruit (blackberries, raspberries, bilberries, blackcurrants and redcurrants), fresh sweet red or green peppers, tomato leaves, natural dried vanilla powder or pods, or shelled walnuts.

Bitter - Bitterness is not detected by about 30% of people. Essentially it causes a reaction transient on the middle palate and on the sides of the tongue. Bitterness is a characteristic taste of oil obtained from green olives or olives turning color.

Pungent - Biting tactile sensation characteristic of oils produced at the start of the crop year, primarily from olives that are still unripe. Pungency starts in the mouth and had a delayed reaction in the throat. Pungency often causes a cough reaction and highly pungent oils are often referred to a "three cough" or "four cough" oils.

Note: When evaluating an olive oil, the positive attributes should be not only present but also balanced.

All negative attributes in olive oil come from either defective fruit, or poor processing techniques. Poor techniques can impart additional negative attributes like In addition to these negative attributes, olive oil can also have the following additional negative attributes : metallic (from contact with metals during processing), heated or burnt (from excessive or prolonged heating of the paste), greasy (due to residual petroleum grease on machinery), and earthy (from soiled or unwashed olives).

Fusty - Fustiness is the characteristic flavor of oil obtained from olives stored in piles which have undergone an advanced stage of anaerobic fermentation. In short, fustiness has a olfactory characteristic similar to dirty socks.

Musty-Humid - Mustiness is the characteristic flavor of oils obtained from fruit in which large numbers of fungi and yeasts have developed as a result of its being stored in humid conditions for several days. Olives stored in bins can mold very easily and very quickly. Thus, mustiness is a very common defect.

Muddy sediment - This is the characteristic flavor of oil recovered from the decanted sediment in vats and underground tanks.

Rancid - Rancid is the flavor which is imparted in an oil after it has undergone the process of oxidation. Since prolonged contact with oxygen is the rot cause of oxidation, rancidity is a common defect.

Winey-vinegary - This defect is essentially reminiscent of wine or vinegar. This flavor is mainly due to a process of fermentation in the olives leading to the formation of acetic acid, ethyl acetate and ethanol. This can result from windfall olives that have sat on the ground for some time of from olives that have been stored too long before milling.