How can you differentiate between good and bad olive oil? The winning test, which allows you to evaluate the organoleptic characteristics of extra virgin olive oil, is tasting. A journey that engages all senses: sight, smell, taste and touch and helps you to recognize the attributes of olive oil according to the definitions developed by the International Olive Council (IOC).
During tastings, the IOC advises detecting the following: the possible presence of defects and their intensity; the intensity of the fruity aroma; whether the olives used were "green" or "ripe"; the intensity of the bitterness; the intensity of the spiciness.
Visual analysis
Visual analysis is generally not used to evaluate the quality of extra virgin olive oil. For this reason, the official color of oil tasting glass is blue or amber.
The visual aspect is taken into consideration only for some specific oils, such as the DOP ones.
However, it is always advisable to check the clarity of the product (a generally positive factor) and the presence of a deposit at the bottom of the container (potentially negative factor).
Olfactory analysis
The sense of smell allows you to perceive smells directly, via the nose, (which can be defined as aromas, perfumes or bouquets), and aromas in the mouth via retronasal smell using the channel that connects the throat with the olfactory receptors. When the oil is in the mouth, it releases a large number of aromatic molecules.
The combination of taste and retronasal smell usually determines the flavor of a food or drink. The sense of smell is particularly involved in the recognition of a flavor, in its absence, for example, due to a blocked nose, it is almost impossible to perceive the flavor of the food.
In the first phase of tasting, the sense of smell is used externally, i.e. the nose, to identify the mixture of different smells (aromas) that determine the specific characteristics of the product. An oil can evoke a "green olive fruitiness" if the scent recalls that of fresh or herbaceous fruits and a "ripe fruitiness" if it recalls the smell of sweet fruits.
These are the steps to perform the olfactory analysis directly(via the nose):
Oil loses its aroma and flavor with oxidation and heat. To try this first hand, heat some olive oil in a saucepan and taste it then compare it to unheated olive oil: the olfactory and taste differences will be significant.
This phase of tasting evaluates all sensations perceived when the oil is in the mouth: detecting both taste and aromas and tactile sensations felt in the oral cavity.
The typical tastes are bitter, sweet, salty, sour and umami (the fifth flavor of basic taste discovered in Japan in the early 1900s) and are perceived by different parts of the tongue despite some areas being more perceptive of specific tastes. For example, the bottom of the tongue appears to be more sensitive to bitterness.
The most common tactile sensations that are perceived when tasting food or drink are spiciness, astringent, temperature, density and fatness/greasiness.
The following are the steps to perform a tasting analysis:
Tip: To avoid the halo effect between the tasting of one oil and the other, it is best to drink some water or eat an apple slice in between tastings.