Tasting Extra-virgin Olive Oil
Professional Sensory Analysis
Below, we’d like to give you a short introduction to assessing the fragrance and flavor of extra-virgin olive oil using the panel test
How do you know if oil is good or not?
The best – official – way to assess olive oil is to have its chemical properties analyzed in a lab and do a panel test with judges who evaluate the attributes of virgin oils.
The Panel and the Chairperson
The panel is a group of 8-12 professional tasters.
This system of analysis is reliable because it can be repeated and reproduced.
This means that the final assessment must be:
- Repeatable: The sample analysis is done using the same method and the same lab.
- Reproducible: The sample analysis is done using the same method but different labs.
The tasters on the panel must taste the oil objectively, disregarding personal taste preferences and likes or dislikes.
The tasters must be careful and relaxed in their approach in order to properly assess their sensations.
The key figure is the panel chairperson, who is responsible for selecting, training and monitoring the other tasters.
The chairperson must be an oil expert who can recognize national and international varieties. It is their job to demonstrate the accuracy of the tasting method and the tasters’ skill.
1.Each oil sample must be placed in a blue glass
The first step is important to assess the oil’s color. Here, the focus is on the intensity and slight variances in the sensory qualities of the oil.
You might think that any oil with a nice bottle green color is good, whereas darker, yellowish oil is not as good.
Actually, color is not an indicator of whether the taste is good or not. Oil color is determined by a variety of factors.
For example, sometimes oil color varies based on when the olives were harvested. Green olives harvested just after they have ripened yield clear, bottle green oil, whereas mature olives yield yellowish oil.
In any case, color is not an indicator of flavor
The flavor and properties of each oil sample are the fruit of the entire olive-growing process, the olives themselves and how they have been processed and preserved.
2.Each oil sample must be warmed to 28°C / 82°F
The best temperature to taste oil is 28°C / 82°F.
During the panel test, the oil is placed on a plate that warms the glass to the desired temperature.
Higher temperatures may cause the oil to release volatile substances that can generate negative olfactory sensations.
However, lower temperatures would not render the aromatic structure of the oil volatile enough.
3. Before tasting the oil
To fully appreciate the sensory attributes of an oil, the tasters’ sense of taste and smell must be uncontaminated by other odors and flavors.
The rules of the panel test are:
- No smoking at least 30 minutes prior to the first taste
- No coffee at least 30 minutes prior to the first taste
- No eating one hour before tasting
1. Olfactory test
After the oil reaches the proper temperature, it is crucial to make sure that the glass remains covered until the moment the oil is tasted. Uncovering it would release the fragrance of the oil prematurely, thereby compromising the accuracy of the assessment.
The taster picks up the glass, takes off the cover and holds it up to their nose.
To fully and wholly appreciate all the oil’s olfactory attributes, the taster must inhale slowly and deeply several times, trying to perceive all the positive and negative attributes before moving on to the tasting phase.
2. Taste test
To appreciate all the subtle variances in the oil’s taste, the oil must be rolled around in the taster’s mouth so that it contacts all the taste buds.
Then, the oil is sprayed into the tasters’ mouth. It is important to hold the oil and not swallow it so that the various attributes move between the tasters’ sense of smell and taste while they breathe through their teeth to release the oil’s fragrance and appreciate all its attributes.
Assessment and score
After properly completing these two tasting steps, the tasters spit out the oil and begin assessing the persistence of the oil’s sensory attributes in the mouth.
Each taster’s assessment of each oil sample is recorded in the Extra-virgin Olive Oil Report.
This report contains two sections. In section one, the tasters note the intensity of their perceptions of the oil’s negative attributes and, in the second section, the intensity of their perceptions of the oil’s positive attributes.
Extra-virgin olive oil has no negative attributes, only positive ones.
1.The perception of the intensity of the oil’s negative attributes
The main negative attributes that come up during the taste test are:
- Fusty / muddy sediment: Olives were not properly stored after harvest, causing them to heat up and begin to ferment.
- Musty / humid / earthy: Olives were not stored in a cool, dry place and were left for days piled up in the heat.
- Winey / Vinegary / Sour: Oil that tastes a bit like wine or vinegar.
- Metallic: Oil that has had contact with the metal surfaces of the press for long periods of time.
- Rancid: Oil that has not been properly preserved and has oxidized.
2.The perception of the intensity of the oil’s positive attributes
- Fruity: This refers to the olfactory attributes overall and depends on various factors like olive variety and how the olives were stored before they were pressed, olive quality (i.e. if they are healthy and fresh, green or mature)
- Green: When the smell is typical of unripe fruit, like the smell and taste of green tomatoes, for example.
- Mature: When the smell is typical of ripe fruit, like ripe apples or pears.
- Bitter: A distinctive attribute of oil from green or ripe olives that resembles artichokes
- Pungent: An attribute that overwhelms the senses and is most strongly perceived in the mouth and throat.
All the oil’s attributes, both negative and positive, are recorded in a sensory and structural profile.
The goal is to identify the attributes of each oil sample and categorize it.
The panel chairperson determines the final assessment based on the tasters’ individual assessments and, using statistics, puts each oil into a category.
One question that always comes up regards the percentage of positive attributes that a good extra-virgin olive oil must have.
The table below shows the intensity range of the attributes followed by an explanation of what is considered good quality oil.
The positive attributes, like the negative ones, are assessed using the senses and get a score of 1-9 for their level of perceived intensity.
Remember that extra-virgin olive oil has no negative attributes. So, for now we’ll focus on the positive attributes.
You might think that good extra-virgin olive oil must have a high score both in terms of its fruitiness and in terms of how bitter and pungent it is.
For example, an oil with a fruity score of 9, bitter 9 and pungent 9 could be seen as a strong, intense, fragrant oil. However, actually, oil is only truly good and high quality when there is a balance.
If the positive attributes get the highest score in terms of their intensity, it would be difficult to clearly distinguish the sensory differences and the oil would leave an unbalanced taste in the mouth.
So, for example, excellent oil is intensely fruity compared to its bitter and pungent attributes.
However, there is no standard score for each attribute. What is ideal is that the overall sensation is pleasant and balanced.
We hope this brief overview of oil tasting and professional oil assessment has been useful.
If you’re interested in tasting your oil at home, click here for a fun, simple explanation of how to taste oil with your family, friends or even just for a new way to spend an evening!