Panel Test: What It Is and How It Works.

 

The Tasting Glasses

 

Once again the purpose and the procedures of the Panel Tests are codifed by the International Olive Oil Council.

As stated in the COI/T.20/Doc. No 15/Rev. 10 2018:

“The purpose of this international method is to determine the procedure for assessing the organoleptic characteristics of virgin olive oil and to establish the method for its classification on the basis of those characteristics. (…) The method described is only applicable to virgin olive oils and to the classification of such oils according to the intensity of the defects perceived and of the fruitiness, as determined by a group of tasters selected, trained and monitored as a panel.”.

 

The IOC describes and codes every detail of the way a Panel Test has to be conducted: from the glasses to be used (their shape, colour dimensions ect), to the Test Room Installation, to the temperature of the oils tasted, the temperature of the room and so on.

 

All these details have the scope of standardizing as much as possible the evaluation process.

For example the IOC states that ideally the test should be held in the morning between 10 am and 12 am (although this rule in particular is in my experience rarely respected, due to working issues of the panel members).

Among the detailed codes of conduct for the tasters: “They must remain silent while performing their tasks.” and “They must keep their mobile phone switched off at all times to avoid interfering with the concentration and work of their colleagues.”

The Tasters as well as the panel leader are selected and trained according to a standardized method.

The Tasting room is standardized as well as the number of tasters componing a Panel (“Between 8 and 12 tasters are required for each test, although it is wise to keep some extra tasters in reserve to cover possible absences.”).

The key concept is that the IOC aims at reducing all the chances of human subjectiveness when it comes to judging a virgin olive oil.

So if you were to observe an official tasting session, it would really appear quite "dull". Each taster sits in silence in his/her cubicle. In the cubicle he/she will find the coded glasses containing the olive oil samples, the tasting sheets, a pen, paper napkins, a spittoon, sparkling water and possibly slices of green apple to bite if needed between each tasted sample. The panel leader controls that every thing takes place regularly and gathers the tasting sheets at the end of the session.Only when all tasters have concluded and handed in their tasting sheets will they speak and make comments among each other.

If you are interested in all the details of the Organoleptic analysis, here is the link to the documents of the IOC.



Extra Virgin Olive Oil's Positive Attributes

Today I'm talking about my favourite part of an Olive Juice; the part which makes me smile! Its positive attributes.

As you can see from the Tasting Sheet below (it's the same as the one of the previous post), they are three: “Fruity” (which is perceived through olfactory and retrolfactory sense), Bitter and Pungeant.



Once again, for the precise definition of the Attributes, I quote from the glossary of the IOOC :

Fruity: “Set of olfactory sensations characteristic of the oil which depends on the variety and comes from sound, fresh olives, either ripe or unripe. It is perceived directly and/or through the back of the nose.”

Within the Attribute of Fruity we can define "Green" (if the sensation reminds us of unripe olives) ore "Ripe" (ripe olives). It is not so uncommon that an Olive Juice presents both Green and Ripe flavours. Moreover there is a whole variety of descriptors of fruitiness (artichoke, green grass, ect.) which we will hint to in the following posts.

Pungent “Biting tactile sensation characteristic of oils produced at the start of the crop year, primarily from olives that are still unripe. It can be perceived throughout the whole of the mouth cavity, particularly in the throat.”

To this definition the only thing I need to add is that the type of "Pungeancy" that I personally prefer... that I consider most harmonic, is the one that covers the Whole top of the tongue, rather than the throat.

Bitter “Characteristic primary taste of oil obtained from green olives or olives turning
colour. It is perceived in the circumvallate papillae on the “V” region of the tongue.” ... Regarding Bitterness, I find that this attribute deserves some extra attention.


ALL Extra Virgin Olive Oils present some level of Bitterness measured in at least 1.
All too often I still hear people say things like “I tasted an EVOO that was no good because it was bitter”. These sorts of phrases make the hairs at the back of my neck stand up! A Fresh Extra Virgin Olive Oil has to have some level of Bitterness. Why? Because Extra Vrgin Olive Oil is nothing else than Olive Juice. And if you ever taste a Fresh Olive.... you will immediately notice that fresh Olives ARE a BITTER FRUIT.

I will never repeat this enough. EVOO has to be at least a little bit BITTER.

If the median of the Bitterness is comprised between 1 and 2 we can say that the olive oil is MILD or “SWEET” (but please notice its just away of speech... virgin olive oils are NEVER actually sweet.).
Between 3 and 6 we say that a EVOO is MEDIUM.


From 6 and above we say that it is “INTENSE” or “ROBUST”.

Again, independently from whether you like it or not, Bitterness is a positive attribute. And it is also (often) an indicator of the amount of Polyphenlos contained in the Olive Oil.


 
Moreover, Personal TASTE has to be distininguished from the Positive Attributes, we are talking about.

In fact, an EVOO might have high scores in all its positive attributes and might be completely free of defects, but it still might not be of your taste.

Personal subjective taste is different from the objective description which comes out as a result of a panel test.

 

Once you have identitfied the quality of an Olive Juice, by detecting and by measuring its Positive Attributes and (if any at all) its defects, then you are completely free to like it or not.

I am personally fond of Robust EVOOs. I love the way they enhance certain types of regional Italian recepies and I look forward to posting on possible pairings between Extra Virgin Olive Oils and food!
 
I hope you enjoyed reading and
Happy Tasting!!


The Negative Attributes

 

To decide whether a Virgin Olive Oil is acutally ExtraVirgin or not, the detection of defects, or negative attributes, is a keypoint.
The organoleptic analysis (tasting) is a powerful instrument to catch possible faults that can remain hidden from the chemical analysis. To tackle this aspect of tasting, I shall start by showing you the Official Tasting Sheet.



Tasting Sheet. Downloaded from: http://www.internationaloliveoil.org/estaticos/view/224-testing-methods (consulted on 19.03.2019)

 



 

This is the Tasting sheet used uniformly by all ufficial panel tests of the countries members of the International Olive Oil Council, to establish whether an olive oil is extra-virgin, virgin, ordinary virgin olive oil or lampante at a sensory organoleptic analysis.

On this page http://www.internationaloliveoil.org/estaticos/view/224-testing-methods

at the section ORGANOLEPTIC ASSESSMENT METHODS you will find all the useful (official) information about regulations on olive oil.I find especially useful the Glossary part.

I you don't have time to read throughout all the documents... I'm here for this! :-)

Here is a summary of what I think are the main traits to be remembered.

As you might see, the classification of Virgin Olive Oils made by the OOC (or IOOC) seems to be explicitly designed to be confusing for the consumer. My personal sensation is that it has been designed to be confusing in order not to penalize the Great Mass Distribution olive oils compared to the high quality etra virgin oils. But, again... this is my personal opinion.

The fact that I quote the OOC costantly is not synonym of agreement with the method. In fact I deeply believe that it should be changed. However the main Olive Oil Producers of the World are members of the Council and follow its classifications, so this what we have to refer to.

So, according to the IOOC (see link above): “ (a) Extra virgin olive oil: the median of the defects is 0.0 and the median of the fruity attribute is above 0.0;
(b) Virgin olive oil: the median of the defects is above 0.0 but not more than 3.5 and the median of the fruity attribute is above 0.0;



(c) Ordinary virgin olive oil: the median of the defects is above 3.5 but not more than 6.0, or the median of the defects is not more than 3.5 and the median of the fruity attribute is 0.0;
d) Lampante virgin olive oil: the median of the defects is above 6.0."

Therefore: To be classified as Extra-Virgin, an olive oil must be completely free of defects and must be at least a little bit fruity.

This is why learning to detect the defects is so important for us consumers!
 
Here are the main and most common defects:


Fusty/muddy sediment :“Characteristic flavour of oil obtained from olives piled or stored in such conditions as to have undergone an advanced stage of anaerobic fermentation, or of oil which has been left in contact with the sediment that settles in underground tanks and vats and which has also undergone a process of anaerobic fermentation.”(from COI/T.20/Doc. No 15/Rev 10 2018 paragraph 4.1 – http://www.internationaloliveoil.org/estaticos/view/224-testing-methods -consulted on 19.03.2019).

 

... This is the typical odour that used to be present is old traditional mills.

Luckily in quality, modern mills this odour is not to be felt anymore, however in the back of many of them you might find an area where the left-overs of the olives are collected to be taken away and used to make pomace oil or fertilizers. If you manage to reach that area, you will notice that there the air is pervaded with a pungeant smell. That is exactly the odour of muddy sediment.

Also another odour which in my mind is related to Fusty is rotten fruit. Fusty/Muddy sediment is for my experience the most common defect that can be found.

 

“Musty-humid- earthy” "Characteristic flavour of oils obtained from fruit in which large numbers of fungi and yeasts have developed as a result of its being stored in humid conditions for several days or of oil obtained from olives that have been collected with earth or mud on them and which have not been washed.“ (cit.)
 
...Luckily I have felt this defect extremely rarely. In fact nowadays quality farmers and producers tend to have great care of their olives and the culture of pressing the olives quickly after the harvest is becoming a more and more a commonly accepted practice in Italy. Is is extremely rare nowadays that a farmer would keep its olives for a week or longer sitting before pressing them and very importantly: modern mills all wash the olives well before pressing them.



“Winey-vinegary” "Characteristic flavour of certain oils reminiscent of wine or vinegar.”
...Even in this case, nowadays in Italy this defect is quite rare. 

 

“ Acid-sour”  “This flavour is mainly due to a process of aerobic fermentation in the olives or in olive paste left on pressing mats which have not been properly cleaned and leads to the formation of acetic acid, ethyl acetate and ethanol.”

... This defect was for me the easiest to learn and detect. However it is normally very detectable at the first sniff. I noticed that already at the second sniff, I tend to not feel it as strong. This is why concentration on the first sniff is so important.

“Rancid” “ Flavour of oils which have undergone an intense process of oxidation.” 
Even if the term “rancid” is often used in every days speech. Actually the defect “rancid” is not as common (in my experience) as Fusty. It is often typical of old olive oils so its presence might be an indicator of not-freshness or even of an olive oil wich results from a blend between an old one and a fresh one.  Moreover it was for me not so easy to detect at the beginning.



Rancid Defect reminds me at times of the scent of dried-wall nuts or of the odour of seasoned salame.

“Frostbitten olives (wet wood)“ "Characteristic flavour of oils extracted from olives which have been injured by frost while on the tree.”

...This defect is for me quite easy to detect because of the description of “wet-wood” added to it. It is not common, since the harvest Europe is done in Autumn when the temperatures aren't below freezing temperatures. However there have been some years when exceptional frosbites have arrived early and damaged the olives causing te insurgence of this defect.

 

For what concerns the other descriptors of negative attributes. I must say that some are extremely rare and are mostly related to old-fashioned ways of pressing the olives or of storing them. For example the defect of "metallic" or "cucumber" can be related to a wrong storage method in tin cans which have not been seeled properly. The defect of "heated or burnt" is in Italy also quite uncommon and can be caused by something gone wrong in the mill system if the temperature has risen clearly over the 28°C during pressing or malaxation.

The sentor of "Dry Hay" is often related to Rancid defect therefore can show an Oxydation defect.

 

A very important point is that, once we have assessed the presence of a defect, this does not mean that we don't like to Olive Oil. Defining the presence or absence of certain attributes is very different from loving or not loving an olive oil. In some situations a virgin olive oil can have a hint of a defect but still be much more appreciable than a Supermarket-Shelf  Ordinary Olive Oil which is free of defects but also of any kind of positive scent! This is why, together with the defect we Always have to keep in mind the positive aspects of an Olive Juice... which will be the topic of the next post!

 

Please let me know if you found this post clear and/or useful and if you would like to read more of these.

 

Happy Tasting!!