Virgin olive oil guided tasting at Jaén University

OliveOilTour Articles

Virgin olive oil guided tasting, led by Diego Fernández and Teresa Cotes, professors of the chemical engineering Department of Jaén University.

On the 16th of November 2011, we have participated in a guided olive oil tasting. It has been organized by Jaén University, during Science Week. The tasting was led by Diego Fernández and Teresa Cotes. They have developed the following points which we report below, in a question-answer format.

What is virgin olive oil?

Firstly the definition of virgin olive oil:
It is a juice* obtained from the fruit of the olive tree solely by mechanical means, without the use of chemical and/or biological means. Any other oil, for instance obtained from seeds, needs a refining process which, for this reason, cannot be considered “virgin”.

  • universidad jaen universidad jaen2

(*Initially the description of virgin olive oil as a juice may seem a little strange but bearing in mind that the olive is a fruit, it makes sense.  The olive is simply pressed in order to obtain the oil…)
Professional tastings are performed to separate olive oil into three grades or qualities. The classifications of virgin olive oils are: “lampante”, virgin and extra virgin.  Those with defects are called “lampante”, the next grade up is called virgin, and the oils which present excellent organoleptic (bouquet and taste) qualities are called extra virgin.

What is the process of elaboration?

The commonly used word is extraction or process. Professor Diego Fernández likes to emphasize the word elaboration because it also contains the will, dedication and care of the producer to create a high quality olive oil.
Olive oil is at its best when it is still in the olive, on the tree. From the moment the olive is picked it starts to loose properties. Olive oil does not improve with the time, unlike wine, but keeps on deteriorating.
This is why it is important to take care of the fruit so that it maintains an optimum quality during each step of the elaboration.  From the moment it is being formed on the tree and throughout its harvesting, extraction and storage each of these steps is controlled to obtain a top quality olive oil.

For example, hand collecting olives ensures that they remain in the healthiest condition and provides the gentlest handling of the tree. Nowadays there is a two phase extraction system which is the most advanced method.  Apart from being environmentally friendly, as it creates less waste, it makes a better quality olive oil as it dispenses with the need to add any extra water during the process. Equally, the sedimentation process (which lasts between twenty days to a month) is very important. Little by little, the small particles made of water and sediments separate and sink to the bottom of the vats. If this is not well done, the oil could get a defect called fusty/ muddy sediment (smell and taste of stagnant water). In all the steps it is very important to avoid the olive oil’s two worst enemies: light, which increases its oxidation, and heat.  At temperatures any higher than 28 degrees Celsius all the rich and healthy substances of the oil are destroyed, as they are volatile!

Why is extra virgin olive oil nowadays better than ever?

Many people are nostalgic towards the past and tend to think that everything used to be more natural, healthier and prettier. This can be true of some things but, to be a little objective, in the case of olive oil it was actually quite difficult to obtain an oil free of defects, mainly because of the working conditions and people’s habits.

The olives were collected with the “vareo” method of shaking the tree with long sticks which can damage them easily. The olives were then gathered up from the ground and squeezed into sacks where the air couldn’t circulate.  This caused fermentation to happen and, as they were so tightly packed, the olives started to burst open and get damaged. They were transported that way to the mill on a mule’s back; a journey which could take quite a time. In the mill, because the sacks were stored one on top of the other for a few days in the “trojes” (outside compartments), this caused the process of oxidisation and fermentation of the olives to continue. They were then crushed by huge mill stones which were turned by a mule and this was time consuming. The pressing was done with woven mats made of straw which were difficult to clean and finally the olive oil used to be stored in ceramic or steel vats with all the residue at the bottom.

Nowadays, sometimes methods like the “vareo” are still used, although most production is done using modern machines that are more efficient and cause less damage to the tree and its fruit. Fortunately 99% of Spanish producers use modern technology which guarantees a better quality olive oil. This is a far greater percentage than most of the other olive oil producing countries.

Let’s remember that nowadays, thanks to technology and research, it is possible to obtain a top quality olive juice, but most importantly, it is the dedication of the olive tree grower and the olive oil producer that makes the difference.

What are the health benefits of extra virgin olive oil?

Good quality extra virgin olive oil, apart from being a pleasure for one’s palate and enriching one’s cuisine, provides a wonderful fountain of health!
It is an antioxidant; thanks to its numerous polyphenols it fights the free radicals and delays the cell’s ageing process, it is an anticancer agent, it helps digestion, it is good for the circulatory system, it prevents oedemas, it fights bad cholesterol and helps to increase the good one, it protects the valve between stomach and oesophagus thus helping to avoid gastric reflux, etc.

How does a professional tasting take place?

During the tasting our nose and mouth are the main tools to appreciate the aromas of the oil. Savouring the oil in the mouth while inhaling it’s aroma through the nose enables us to sense the aroma in a retro nasal way while tasting it in the mouth. The combination of: aroma + tactile and gustative sensations = flavour.

Positive attributes

The first thing that we want to find in the smell and taste of olive oil is the olive itself. Depending on the degree of maturity of the olive, the aroma of the oil can be described as green fruitiness or mature fruitiness. The “green” can feel very fresh, like freshly cut grass, or a little more mature like a leaf or even more, like a stem.

Depending on the olive variety (263 in Spain), the oil presents different characteristics that can remind us of other fruits such as apple, banana or herbs such as rosemary, thyme, fennel, mint, sage, lemon verbena…
Sensations of bitterness, pungency and astringency are always considered good attributes. They show the antioxidant and healthy properties of the oil.

For example, the picual variety (the most cultivated in Spain and especially in Jaen’s region) can be distinguished by its taste and smell of tomato or tomato plant. It can also remind us of almond, as it produces astringency in the mouth. This may be either the green bitter almond or the peeled mature almond if the olives were ripe when picked. Olive oils from La Mancha, from Monte de Toledo taste of artichoke while those from the Tabernas Desert have a slightly spicy taste like chilli pepper because of the arid conditions where the olives grow. A Portuguese variety called galega produces olive oils that smell like wild berries and taste like raspberries or blackberries… In the Navarra area the empeltre variety reminds us of hazelnuts and walnuts.  The arbequina variety gives a sweet flavour that can be felt on the tip of the tongue…

Negative attributes / defects

When a professional taster tastes an olive oil, he/she wants to distinguish the positive attributes from the negative ones. If an oil has one of the following defects it cannot be considered virgin or extra virgin.  Consequently it would be classified as lampante and would need to go through a refining process in order to be consumed:

Winey, vinegary, acid-sour, musty-humid-earthy (from olives that have been picked on the floor), fusty/muddy sediment (oil which has been left in contact with the sediment that settles in underground tanks and vats), and rancid defect is due to a loss in the oil stability. The olives that have been injured by frost give a cooked flavour, as if the oil had been cooked.

During the guided tasting, we tasted two oils. The first one was defective, so we can train our palate to recognize the biggest defects that an oil can have.  The second one was delicious. It was from the Jaen area, with the Sierra Magina Designation of Origin and was made with freshly pressed picual olives! What a delight!

It is important to taste all types and qualities in order to learn how to differentiate between olive oils. Anyone can get to enjoy this art of tasting, with a little application, time, and especially with a lot of love for high quality extra virgin olive oil! Cheers!

Violeta, guide for OliveOilTour.