We asked Nancy Ash, one of the most respected tasting experts in the U.S., to write this page for The Olive Oil Source. We think it is the best description of tasting olive oil we have read. Here is what she recommends.
If a picture is worth 1,000 words, then how many words is a taste worth? In order to appreciate the range of flavors in olive oils, one must go beyond reading about oil and be willing to experience the act of tasting it.
What factors determine the taste of olive oil?
Flavors in olive oil are determined by a wide range of factors including the type of olive (varietal), ripeness at harvest, growing conditions (climate, soil type), crop maintenance (irrigation, pest control), handling of fruit from tree to mill, and the milling process itself. For example, oil made from predominantly unripe (green) olives contain flavors described as grassy, artichoke, or tomato leaf, whereas riper olives tend to yield softer flavors often described as buttery, floral, or tropical.
The above descriptions are associated with good olive oil quality, but trained tasters also learn to identify negative characteristics. 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 prior to milling), certain milling conditions (unsanitary equipment, excessive heat), and improper or prolonged storage after milling (oxidation). An oil that is determined to have flavor defects is not of genuine extra virgin quality; according to the International Olive Council extra virgin oils must meet both chemical and organoleptic (flavor) standards that include the absence of flavor defects.
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, salt, sour, bitter, and umami (the flavor of protein). All other information that we think of as flavor is actually perceived by smelling food through the back of our nostrils (retro-nasally) while it is in our mouths. To illustrate this fact, think about how little flavor we perceive when we have a cold – this is because one cannot smell food retro-nasally when one’s nose is stuffed up.
When tasting olive oil, much of the oil’s characteristics are perceived through the sense of smell. Though most people enjoy olive oil with other foods, the following steps allow us to focus on the olive oil’s flavor without distraction:
- Pour a small amount of oil (about 1 tablespoon) into a small tapered (wine) glass.
- Hold the glass in one hand and use your other hand to cover the glass while swirling the oil to release its aroma.
- Uncover the glass and inhale deeply from the top of the glass. Think about whether the aroma is mild or strong. You may want to write down descriptions of the aromas that you detect at this point.
- Next you slurp the oil; this is done by sipping a small amount of oil into your mouth while “sipping” some air as well. (When done correctly, you will make that impolite noise that would cause you to be scolded when you were a child!) Slurping emulsifies the oil with air that helps to spread it throughout your mouth - giving you the chance to savor every nuance of flavor with just a small sip of oil.
- Finish by swallowing the oil and noticing if it leaves a stinging sensation in your throat.
Each of the above actions focuses our attention on a specific positive attribute in the oil. First we evaluate the olive fruit aroma (fruitiness) by inhaling from the glass. When the oil is in our mouths we further evaluate the aroma retro-nasally as well as determine amount of bitterness on our tongues. Lastly we determine the intensity of the oil’s pungency in our throats as we swallow it.
Is color an indicator of an olive oil's flavor or quality?Perhaps you noticed that the oil’s color is not addressed during sensory assessment. The reason is that contrary to the common belief that golden oil is mild and dark green oil is robust, color is NOT an indicator of either the oil’s flavor or quality. In fact, in scientific assessments, we sample from specially designed blue glasses that obscure the color of the oil. Tasting from a dark glass prevents us from having preconceptions about the flavor of the oil before we actually smell or taste it.
TRY THIS EXERCISE
Once you are comfortable with the above tasting method, try the following exercise. Select three oils labeled as extra virgin, including an inexpensive imported brand from the supermarket. In between samples, clean your palate by eating a small piece of tart, green apple (preferably Granny Smith) and then rinsing your mouth with water. Consider the following as you evaluate each sample:
- Is the aroma pleasant or unpleasant?
- Is the aroma mild, strong, or somewhere in the middle (we’ll call that medium)? When assessing the second and third oils, note if the aroma’s intensity is weaker or stronger than the previous sample.
- Note 3 words (or phrases) that describe the aroma.
- Is the oil bitter, which is primarily sensed towards the back of the tongue? Would you describe the bitterness as mild, medium or strong? Is the intensity of the bitterness in balance with the intensity of the aroma?
- When you swallow the oil, how does it feel in your throat? Did the oil leave a mild impression, or did it sting your throat or make you cough? Is the intensity of the oil’s pungency in balance with the oil’s aroma and bitterness?
When you have completed the above exercise, take a few moments to review your notes. What were the characteristics that you enjoyed the most? Were there any characteristics that you didn’t enjoy? How did the supermarket brand compare to the other oils? Even without an experienced taster sharing their thoughts about the oils with you, there is much you can learn by tasting olive oils on your own.
Using this same tasting method, you can sample another set of oils on another day, and still be able to compare your responses to the first set; this is how we build our personal olive oil “vocabulary”. You will begin to recognize flavors and may even discover which varietals produce the flavors you prefer. You will learn to compare the level of intensity for fruity aroma, bitterness and pungency, and will begin to identify oils as mild, medium and robust (intense). It’s a good idea to organize your tasting notes in a binder so you can review your past tasting experiences with new ones.
Worldwide over 1,000 varieties of olives are grown, which should give consumers a wide range of flavor possibilities. Taste is personal, so not everyone will agree on which varietals, and other factors, produce the best oil. However, tasting oils in a methodical fashion will help to educate your palate, and you will be able to select oils with flavor characteristics that you enjoy and enhance your meals.