Tasting Olive Oil

In order to categorize an olive oil, the taste is as important as chemical analysis. Olive oil is the only food required to undergo a trained and approved panel test to prove its category statement.

To be able to label an olive oil as Extra Virgin, there must be no defects in its taste and must at least just perceptibly fruity.

Flavor defects in olive oil are associated with problems with the olive fruit (olive fly, frozen conditions), improper handling of olives during harvest (dirt, wet fruit, prolonged storage before milling), certain milling conditions (unsanitary equipment, excessive heat), and improper or prolonged storage after milling (oxidation).

The first step in learning how to taste olive oil is to understand how our senses work. Perception of flavor relies on both our senses of taste and smell. The ability to taste is quite limited; receptors on our tongue can only discern sweet, salty, sour, bitter, and umami. All other information that we think of as flavor is actually perceived by smelling food through the back of our nostrils (retronasally) while it is in our mouths.

Knowing the facts above, we undergo this process:

1) Pour two tablespoons into the cobalt blue olive oil tasting glass, or a glass for white wine or a glass for cognac.
2) Cover the bottom of the glass with your hand to help the olive oil warm up while simultaneously covering the top of the glass. This will help release the aromas and flavors of the olive oil.
3) Swirl the glass for a couple of minutes and allow the olive oil to reach all.
4) Release the hand covering the glass. Instantly sniff a couple of times the olive oil and then take a deep breath to sense the fruity attribute.
5) Sip a small amount of the olive oil. Close your mouth well and draw in air through your teeth, delicately first and more intense after, while breathing out through your nose. Here you must sense the bitter attribute.
6) Now you can either expel the olive oil or continue by swallowing the olive oil to sense other things about this olive oil.
7) Right after you swallow the olive oil, the phenols of olive oil will start a reaction in which you will feel as a tingle in your throat and might be as strong as to make you cough 1-2 times. This is the pungent attribute that is absolutely normal to happen and it is proof of olive oil quality.

Finally, here are some common attributes of olive oil:

A) Positive:

• Astringent: dry and puckering mouthfeel created by tannins mostly appearing in bitter and robust olive oils
• Buttery: creamy, smooth sensation on palate
• Floral: perfume/aroma of flowers
• Forest: fresh aroma reminiscent of forest floor, NOT dirty
• Fresh: good aroma, fruity, not oxidized
• Fruity: refers to the aroma of fresh olive fruit, which is perceived through the nostrils and retronasally when the oil is in one’s mouth.
• Grass: the aroma of fresh-cut (mowed) grass
• Green: aroma/flavor of unripe olives
• Harmonious: balance among the olive oil’s characteristics with none overpowering the other
• Herbaceous: unripe olive fruit reminiscent of fresh green herbs

B) Negative:

• Acetone: the aroma of nail polish remover, associated with the winey defect
• Blue Cheese: aroma associated with muddy sediment defect
• Burnt/Heated: caused by processing at too high a temperature
• Cucumber: off flavor from prolonged storage, particularly in tin cans
• Dirty: oils that have absorbed unpleasant odors and flavors of dirty waste water during milling
• Flat / Bland: oils which have no positive or negative aroma or flavor characteristic of olive oil; may indicate the presence of refined olive oil
• Frozen / Wet Wood: sweet, dry, and typical aroma/flavor derived from olives that have been exposed to freezing temperatures
• Fusty: anaerobic fermentation that occurs when olives are stored in piles too long before milling
• Grubby: flavor imparted to oil by olive fly damage to olives
• Haywood: flavor of dried olives
• Muddy Sediment: barnyard-like aroma caused by olives’ prolonged contact with dirt before or after milling
• Musty: moldy, humid flavor 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 flavor of oxidation that occurs as olive oil ages, often described as “stale nuts”
• Rough: nasty, thick, greasy mouth feel
• Unbalanced: olive oils with overwhelming flavors of bitterness and pungency
• Winey /vinegary: sour flavor caused by aerobic fermentation of olives during processing

Sources:
http://www.internationaloliveoil.org/
http://www.wikipedia.org
http://www.oliveoilsource.com