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