Olive oil, history, processing, characteristics of a great product

Last updated on
Olive oil
(Image by Marge Nauer from Pixabay)

Olive oil: it must have acidity in a percentage lower than 0,8% when the extra virgin, the label must show all the characteristics.

How olive oil is obtained

It is obtained thanks to the pressing of the olives, a purely physical operation without any addition of external additives, to be considered olive oil.

Monounsaturated fats

It demonstrates particular organoleptic qualities, and holds a good percentage of monounsaturated fats (healthline.com), which help the transformation of LDL (Low Density Lipoprotein) cholesterol into the blood, a possible cause of vascular obstruction, with HDL (High Density Lipoprotein) cholesterol.


Fossil traces of the olive tree, trace its presence even before the presence of the human being.
Its confirmation is also known in ancient legends, as well as cited in Sacred Texts such as the Bible, Koran and Torah.

About 8.000 years ago, Syria probably cultivated the olive tree to get the oil that could be obtained from the fruits.

The Phoenicians and the Greeks contributed significantly to the spread of olive trees and their cultivation on the Mediterranean coasts, crops destined to grow over time.

Used as a currency

The Ancient Romans had the tribute to be paid for various territories, object of their conquest, paid in olive oil.
It was the Romans who developed tools for squeezing olives, and studied techniques for its conservation, perfecting them over time.

The different uses

The olive oil accompanies the human being from its early history, not only for food but also finding a valuable outlet in body care, in massage, in beauty care, also useful for cleaning and hygiene.
Examples are Aleppo soap and Marseille soap.

Several archaeological findings have demonstrated the existence of tools suitable for harvesting olives, for pressing them, giving a very significant historical importance to this fruit for human life.

Its importance in history

The importance that this product covered for ancient populations was truly admirable.
In Ancient Egypt it was considered a gift from the Gods, the Jews used it to anoint their kings, and it was the Greeks and the Phoenicians who built ships used to transport large quantities of olive oil, crammed into huge amphorae.
It therefore also had an enormous value of trade and wealth.

The classification by the Ancient Romans

The Ancient Romans had already classified olive oil in different qualities, based on the degree of ripeness of the fruit at the time of pressing.

Oleum ex albis ulivis
Obtained from green olives.

Oleum viride
Oil obtained from olives with a more advanced stage of ripeness.

Oleum maturum
Obtained from ripe olives.

Oleum caducum
Oil produced from olives that have fallen to the ground.

Oleum cibarium
Which was usable thanks to dried olives.

The olive tree

The olive tree is an evergreen tree, with an average height of 7, 8 meters, but there are even taller specimens, well over 15 meters, whose circumference of the shrub can reach, in the largest specimens, over 5 meters.


The white and particularly fragrant flowers, mignole, develop cluster inflorescences that appear in the ripening period called mignolatura, in April or May.

The fruits of the olive tree, drupes, fleshy, oval fruits, at first take on a green color, then later a purplish-red, ending in black.

The ripening of the olives takes place between October and December and depending on the quality they can be used for pressing, or for food consumption as a fruit.

Prince of the Mediterranean
The olive tree represents the typical tree of the Mediterranean climate par excellence, so much so that the Mediterranean region is delimited precisely, in the western and northern part, by olive groves.

Processing of olives

The extraction of oil from olives is distinguished in several steps.


It is carried out in the mill, it breaks the pulp and the stone of the olives, torn with the use of the muller, the millstone with stone wheels, or with the modern hammer mill.

A paste is therefore produced made up of crushed pulp and stone, the traditional pressing uses granite millstones.

With the most modern hammers, it is possible to obtain a more uniform paste, managing to crush more olives in less time; however, this causes overheating of the pasta which can cause organoleptic alterations.

Therefore, the granite grinder does not guarantee the same production capacity as modern plants in the same space of time.


It consists of a constant reshuffling of the olive paste, thanks to continuous handling; this procedure helps the drops of oil to join together to increase their volume, facilitating what will be the squeezing.

When using a mechanical crusher, this operation also serves to divide the water from the oil, formed during the fast pressing of the olives.


During the pressing, the division between pomace, vegetation water, and oil is carried out in the olive paste.
The paste is placed on filters, vegetable or synthetic fiber discs, and thanks to the pressure that is applied increasingly, it lets the oil escape, going to retain the pomace on the filters.

Separation of water from oil

The definitive separation between oil and water, a percentage always remains, is obtained by leveraging the different specific weights between water and oil.

Oil whiches is then left to settle for a certain period, a few months so that it can deposit any impurities on the bottom, or small particles of water that could not be previously divided.

Product features

The olive oil, to be considered Virgin, or ExtraVirgin, must have very precise quality standards to match these characteristics.

The current legislation in Italy, in fact, defines Virgin Olive Oil obtained from the fruit through purely physical operations and without any addition of additives.

Sensory evaluation

The sensory evaluation of the olive oil food product is subjected to subjective evaluations by each individual called to evaluate.

The most difficult task of the evaluation is to obtain the greatest number of concordant objective evaluations, to establish a reliable judgment, which will then be final.

Given the subjectivity of sensory perceptions, which can also differ greatly from subject to subject, this evaluation is carried out on a large number of people, so that the results obtained can be as reliable as possible.

It is also possible to obtain excellent evaluations by employing a small number of people, about 15: people, however, well trained in evaluating the oil, who have demonstrated good sensory abilities, therefore able to draw up satisfactory olfactory and gustatory opinions, of the product being evaluated.

The tasters

The selected testers are asked to estimate the quality of the olive oil subject to evaluation, trying to better establish the nuances and organoleptic defects of the product.

The evaluation of the tasters

The evaluations are carried out independently, separated from each other, with the help of a guide card (Panel Test) where they assign a score with values ​​from 1 to 9 for each characteristic expressed by the oil.

Average of the evaluation score

An average of the total score obtained is then drawn up, and if the error calculation on the average is reliable, the resulting average value expresses the evaluation of the organoleptic (sensorial) qualities.

Attribution of organoleptic characteristics

Olive oil always has pleasant characteristics.

Harmonious fruity
It can be considered harmonious fruity, with an aroma that recalls the scent and taste of fresh fruit, at a balanced level of ripeness.

Intense fruity
With the same characteristics as above, but characterized by greater intensity.

Green fruity
The aroma that is obtained from the still-green fruit.

Ripe fruity
Characteristic obtained from ripe fruit, with a light aroma and sweet taste.

Tired fruity
Or dull fruity, where the expressed aroma has little developed organoleptic characteristics since, at the time of processing, the disappearance of the aromatic components from the olives has already begun.

The sensations it expresses
All these characteristics are sensations expressed by the olive oil and by the intensity of the harmony of the fruit .
They can recall to the senses the scent of apple, freshly cut grass, or express a sweet, bitter, sour, spicy scent.

Defects and possible causes

There may be several reasons why defects can be found in the product, which ruin the organoleptic characteristics and their perception.

The fruits
They can originate from fruits, which then affect the evaluation, recalling the aroma of the earth to the sensory perception, possible when the olives have not been properly washed.

Or mold, which develops in places unsuitable for storing olives, where they can also undergo a rise in temperature, which deteriorates their taste.

The oil mill
Defects that can also arise from the mill, an oil that gives off a metallic scent, for example, can be typical of new plants, or at the beginning of seasonal pressing.

The filters
Or where the oil is produced with inadequately cleaned filters, or excessive overheating during processing.

Bad conservation
Finally, defects attributable to poor conservation, exposure to sources of heat, light, etc. where the oil oxidizes or remains in contact on its own grounds for too long, developing harmful fermentations.

Olives varieties

Each product belongs to a well-distinguished variety of olives, which characterizes it decisively.
Often, it is not so easy to recognize and distinguish the different varieties of olives, relying only on sensory perception, because the differences are really small.

A study is then carried out on the seeds, their shape, and the flowers produced by the olive tree.
Based on the different degrees of ripeness of the olives, and the techniques used for pressing, the product obtained is divided into different types.

The denomination

The denomination of the olive oil must respond to very specific parameters established by decrees of the European Community.

1) For Extra Virgin Olive Oil means an oil obtained with the sole mechanical pressing at low temperatures, where the acidity (expressed as oleic acid) is less than 0,8% and an organoleptic score of the Panel test is equal to, or higher, at 6.5.

2) Virgin Olive Oil, the same as above for the pressing, with acidity lower than 2% and organoleptic score equal to or superior to 5.5.

3) Olive Oil, it is refined and virgin olive oil is added to improve its taste, the degree of acidity must not exceed 1,5%.

How to choose and buy

The quantity of olive oil required by the Italian market is greater than the production of olives possible on the National territory, therefore, even Italian producers make purchases of olives from other areas of the Mediterranean area.

The quality obtained and offered is of an excellent level, the only qualitative limit is imposed by the expense.

Product information on the label

The important thing is that the product carries all the chemical parameters resulting from laboratory analyzes on the label.

Beyond the subjective tastes to which one oil can be subjected instead of another, certain values ​​must be respected.
The parameters indicated in the paragraph on the denomination above may be useful.

The more data on the product label, the greater the guarantees that the producer can provide, and the higher the quality of the oil, the greater the pride of the producer to show a whole series of data obtained from the analyzes chemical.

Always check the price, and the real content, it is right to doubt an oil that is too cheap, but just as much an excessively expensive one.

Packaging date and expiry date, no later than 24 months after bottling, are basic indications.

An Extra Virgin Olive Oil will show off on the label to have an acidity lower than 0,3%.

The fat content is almost identical in all types of oil, with the difference that olive oil contains an optimal presence of acidic composition, and antioxidants, as well as vitamins.

It is the best type of oil to use in frying.

The price ratio

A product of this type, made as it should, cannot cost too little, for a whole series of logical reasons: quality of the olives, harvesting, selection, etc.

So, although there are products often offered at bargain prices, when that is the case, because pomace and other olive by-products are added together with the oil.

• The price of olive oil, and extra virgin olive oil, also changes according to the vintage, due to the olives available for each vintage.

The packaging

The best packaging for this product is the dark glass bottle, which protects it from possible light alterations.
Metal cans, too, can be valid.

The one packaged in plastic bottles, sometimes even transparent, I do not think is so precious to keep, ergo I would never buy it.


It is good to keep the olive oil at temperatures ranging between 12 and 24°C (53,6°F to 75,2°F) , away from heat sources, and from exposure to light.

Quick answers

What is the acidity of olive oil?

Is that parameter that establishes the quantity of oleic acid fat present, lower this level, higher is the quality of the product. Is a very delicate parameter, which cannot be done distinguish by taste, but only with chemical analysis.
For this reason many oils do not clearly show this value, because of quality rather low.

How much does olive oil cost per liter?

Good question. We can risk a cost of 10.00 € per liter for a quality product, which you can lower to 8.00 € approximately, and go up to 15.00 €. It also depends on the vintages, just like the wine.
These indicative prices are valid for the consumer, to the prices of origin of the oil in the tank, to the wholesale, must be added at least 2.00 € for each liter.
When is obtained only from Italian olives, the price tends to rise compared to products where olives from other Mediterranean countries are used.

What a difference there is between Olive Oil and Extra Virgin?

I refer you to the paragraph that explains the differences between Olive Oil, Virgin Olive Oil, and Extra Virgin Olive Oil, as regards the legal regulations.
The taste, on the other hand, is purely subjective, and a quality product even when not Extra Virgin, it is always a valid, tasty food with properties; healthy to the organism.


Felice Amadeo - af1.it
Since 2006 I have been working with the internet, writing content and managing the site. I've been using WordPress since 2013.
As I got older, I found that I like to wear the hat.