Sensory Analysis EVOO

Professional Sensory Analysis System

This is a concise introduction to the evaluation of the olfactory and gustatory qualities of EVO oil by a Panel.

How can one determine the quality of an oil?

The most official method to assess the quality of an oil is through laboratory analysis of its chemical properties and a Panel Test, where a group of judges evaluates the characteristics of virgin oils.

The Panel and Head Panel

The Panel is composed of professional tasters, typically numbering between eight and twelve experts.

The analysis system is deemed reliable as it guarantees repeatability and reproducibility.

This entails that the final assessment of an oil is based on:

Repeatability: the analysis of the same sample using the same method in a single laboratory.

Reproducibility: the analysis of the same sample using the same method across different laboratories.

The panel of tasters is required to objectively sample the oil, excluding personal taste and pleasure from the evaluation.

Thus, it is essential to work in a calm and focused manner to accurately assess the sensations experienced.

The Head Panel plays a pivotal role, tasked with the selection, training, and oversight of the tasters.

As an expert in oils, capable of identifying both national and international varieties, their duty is to affirm the reliability of the tasting method and the tasters' expertise.

The conditions for oil tasting stipulate that each oil sample should be presented in a blue glass. 

This initial step is crucial as it allows the focus to be on the oil's sensory qualities, such as intensity and nuances, rather than its color. It's a common misconception that a vibrant green hue indicates superior quality, while a darker, yellowish color suggests inferiority. 

However, the color of the oil does not necessarily reflect its taste quality, which is influenced by various factors. For instance, the color may differ based on the timing of the olive harvest; oil from green, freshly ripened olives will have a clear, greenish tint, whereas oil from more mature olives will appear yellower. 

Regardless, the color is not an indicator of taste. The flavor and characteristics of each oil sample are the culmination of the entire olive production process, encompassing everything from the quality of the olives to the methods of processing and storage.

In a Panel Test, the oil is heated in a saucer to reach this temperature. Going beyond this temperature might result in the release of volatile compounds, causing undesirable smells. On the other hand, temperatures below this ideal point may suppress the release of the oil's aromatic compounds.

The temperature for oil tasting is 28° C. 

Before oil tasting, it is crucial to ensure that your sense of smell and taste are not influenced by other odors or flavors to fully appreciate the oil's taste qualities and olfactory properties. 

The Panel Test mandates the following guidelines:

• Refrain from smoking for at least thirty minutes before tasting.

• Avoid drinking coffee for at least thirty minutes before tasting.

• Do not consume any food one hour prior to tasting.

Oil tasting involves a sequence of actions aimed at assessing the oil's scent and taste. This process includes heating the oil in a glass to liberate the aromas, swirling to check the viscosity, sniffing to detect different notes, savoring to distinguish the flavors, and cleansing the palate between different samples.

1. Olfactory Examination

Ensure the oil is at the ideal temperature and keep the glass covered until the moment of tasting to prevent the premature release of aromas, which could affect the accuracy of the evaluation.

Hold the glass, remove the cover, and bring it to the nose.

Inhale slowly and deeply several times to fully capture the complexity of the aromas, identifying both positive and negative attributes before proceeding to taste.

2. Gustatory Examination

To discern all the flavor subtleties, move the oil around your mouth, ensuring it touches all taste receptors.

Nebulize the oil in the mouth without swallowing, allowing the aromas to transition from olfactory to gustatory senses. Draw air through the teeth to release the oil's full spectrum of aromas for a comprehensive assessment.

Evaluation and Scoring

After the precise completion of the two tasting phases, the oil is released, and the evaluation of characteristics based on the persistence of aromas in the mouth commences.

Each taster's assessment for every sample of virgin oil is recorded on a document titled "Virgin Olive Oil Flavor Profile Sheet."

This sheet is split into two parts: the first assesses the intensity of perceived defects, and the second gauges the intensity of perceived positive attributes.

Extra virgin olive oil is characterized by the absence of negative attributes and the presence of only positive attributes.

1. Intensity of Defect Perception

The primary defects identified during the sensory analysis of an olive oil sample include:

- Soot/Heat (a flavor that develops when olives are improperly stored post-harvest, leading to overheating and fermentation)

- Mold/Moisture/Earth (a flavor indicative of oil from olives not kept in cool, dry conditions, but rather left in warm, piled conditions for extended periods)

- Vinous/Acidified/Acid (a flavor common to oils that have a wine or vinegar-like taste)

- Metallic (a flavor that suggests metal, usually caused by prolonged contact between the oil and the metal surfaces within the mill)

- Rancid (a flavor typical of oils that have been improperly stored, leading to oxidation)

2. Intensity of Perception of Positive Attributes:

- Fruity: This encompasses the set of olfactory sensations which depend on factors like the olive variety, storage methods post-harvest, and the quality of the fruit, indicating whether the olives are healthy, fresh, green, or ripe.

- Green: This odor is typical of green fruits and is identified by the scent and taste reminiscent of green tomatoes.

- Ripe: The scent of ripeness is noted when olfactory sensations are akin to those of ripe fruits, such as apples or pears.

- Bitter: A characteristic flavor of the oil derived from green or ripened olives, it may evoke the scent of artichokes.

- Pungent: A 'stinging' sensation that fully engulfs the senses, particularly noticeable in the mouth and throat.