Olive oil is not the same and it is not only useful, but necessary, know classification and differences. Olive oil is an essential resource for our power. Almost everything on the market comes from the great basin of the countries of the Mediterranean Sea. Spain, Italy, Greece, Tunisia is among the largest producers, as we have already told in the article “ITALIAN OLIVE OIL: A EXCELLENCE TO DEFEND AND TO PROMOTE".
But how many types of olive oil are commercially available? And how do you choose the olive oil best suited to our needs? For a healthy and safe food, it is always necessary to buy an oil with the brand a protected designation of origin (DOP) or indication of protected origin (PGI)?
To answer these questions we must first deepen olive oil classification, under current legislation in Italy and Europe. To understand classification and differences of olive oil, you should know that not everything is produced in the same way. Three are in fact the olive oil production methods, that according to these methods, It is classified in olive oil obtained by mechanical pressing, Refined olive oil and pomace olive oil.
Of all the products of olive oils, only 4 are shown in commerce: l & #8217; olive oil, the virgin olive oil, olive oil and olive-pomace oil.
OLIVE OIL OBTAINED BY MECHANICAL PRESSING
At the olive oils obtained from the mechanical pressing belong to three types of oil: extra virgin, virgin and lampante virgin olive oil. For mechanical pressing means a natural method of extraction of oil from olives that does not require the use of chemicals to extract the oil. Olive oil is understood to be "cold extract” when the temperature, during the process of extraction and processing, does not exceed 27 degrees centigrade. The temperature control is essential to avoid that the oil loses some organoleptic characteristics synonymous with quality, such as fruit and vegetable.
Extra virgin olive oil
Also called oil "Evo", extra virgin olive oil is the best oil you can buy, both from an organoleptic point of view, both the healthy. Is’ even the most expensive product. Extra virgin olive oil is obtained from the pressing of fresh olives, by mechanical or physical processes (pressure or centrifugal). It has a free acidity equal to or less than 0,8%: means that out of a hundred grams of oil contains 0,8 grams of oleic acid. The acidity is measured with chemical laboratory instruments. The lower the acidity, the higher the quality of the product. To classify an oil as extra virgin olive oil, we must subject it to organoleptic tests (panel test).
In order to pass the exam organoleptic, olive oil must have precise olfactory: fruity (Lightweight, medium, intense), It must have a bitter and spicy taste. It should have no defects (the median of the defects must be equal to zero). The main defects of olive oil is rancid, reheating, the Winey, la morchia, the mold. They depend on several factors, which they are mainly related to the quality of the olives, the manner and timing of collection. But also to work in the mill and conservation.
The PDO extra virgin olive oil or PGI
The extra virgin olive oil can have different quality marks: DOP, PGI or Organic, which are synonymous with a higher quality oil. Typically, an oil under the trademark designation of origin has an acidity of between 0,2% and 0,3%. The law does not oblige producers to indicate the level of acidity on the label. Those who choose to indicate it, It can only indicate the maximum acidity provided at the date of minimum durability. The acidity indication must be accompanied by other indications. Peroxide value (It must be as low as possible; the maximum limit for the extra virgin is 20 milliequivalents of active oxygen per kilo), wax content and absorption of ultraviolet light (parameter "delta k").
Virgin olive oil
Is’ a marketed oil and is obtained from the pressing of olives by mechanical or physical processes. Its free acidity (grams of oleic acid per one hundred grams of oil) should not exceed 2%. It has minor flaws the organoleptic (panel test). The median of the defects must be greater than zero or equal to 3,5. The fruity median is equal to zero. The virgin olive oil is one of the types of oil that can be sold, but in fact it is almost absent from the shelves of supermarkets. A shame, because it would be a very suitable oil to be used in cooking.
Lampante virgin olive oil
Obtained from the pressing of the olives, It has a free acidity greater than 2%. It does not have suitable characteristics for consumption but is intended for refining. It has obvious flaws, taste and unpleasant smell. For this reason, It must be chemically treated, industrially, to eliminate the organoleptic defects. Is’ obtained from very low or poor-quality olives.
REFINED OLIVE OILS
In the commodity classification of olive oil are then refined olive oils. These oils are extracted in the course of an industrial process that uses chemicals and solvents. subsequently, They are chemically treated. That's why we talk about "refined" oils” or "adjusted", ie treated so as to correct or limit the defects: excessive acidity, defect rancid, color and odor. These oils can be admitted to the human food consumption only after having undergone a chemical refining process which comprises decolorization, deodorization and deacidification.
Refined olive oil
It comes from the industrial processing of virgin olive oils obvious, which they are subjected to deodorization processes, deacidificazione, discoloration. Is’ a colorless oil, odorless and tasteless. Its free acidity may be equal to or less than 0,3%. It is not marketable. From oil refined olive, mixed with virgin olive oil, you get olive oil that you find on the market.
The olive oil should not be confused with the extra virgin olive oil. It is derived from the combination of refined olive oil and virgin olive oil (not clear). You can market. In other words, It is a mix between a virgin olive oil and an oil which has undergone a chemical process of correcting defects (chemical and organoleptic). The acidity is equal to or less than 1%. Usually, virgin oil is added to the oil refined olive until you get the colors back, the smells and the desired flavors.
The law does not require the indication of the minimum percentage of virgin olive oil (or even extra virgin olive oil) that is added to the oil refined. Usually, this percentage is between 5% and l’ 8% (this means that the rest is refined oil). But the best olive oils also come to 30%. The label shows "a mixture of refined olive oils and virgin olive oils". Olive oil is used by the industrial-grade companies for the conservation of foods in oil: vegetables, tuna, etc. Olive oil is suitable to be used as oil for frying. This is because it contains a high percentage of monounsaturated fats, that they are more stable at high temperatures.
POMACE OLIVE OIL
Yet, the classification of olive oil comprises the pomace. A compound obtained by the dry residue of the pressing of the olives in the crusher. The residue consists of skins, Pressed pulp and kernels. Is’ a secondary product in the processing of olives, that contains a percentage of oil comprised between 3% and 6%. This residual oil is extracted by mixing the dried pomace with a solvent (hexane), which dissolves the oil contained within the squeezing residues. The solvent is separated by distillation and the oil is subjected to refining processes, to correct deficiencies.
The European law allows to market pomace oil only after appropriate processes. Then, pomace oil passes through three stages of processing, to get to the last stage, which makes it suitable for consumption. The residue oil is also found application in the industry of cosmetics and the exhausted pomace it can be used as a fuel (pellet) or as a fertilizer in agriculture.
Oil crude olive pomace
Obtained from olive pomace by chemical processes that extract the oil, thanks to solvents, distillations and washes. It is not a marketable or edible oil, but it must be refined.
Oil refined olive pomace
It is obtained from crude pomace oil which is subjected to the refining process. The acidity is less than or equal to 0,3%. It is not marketable and is not edible.
Olive pomace oil
It derives from the combination of refined olive-pomace oil and virgin olive oil. It can be commercialized. The acidity is equal to or less than 1%. It has a high smoke point, which allows it to withstand high temperatures. The olive-pomace oil is, then, suitable for frying food. Its acidity allows it to better withstand other oils (such as extra virgin) Prolonged frying.
NOTE: Standards applied in the European Union.
Reg. CEE n. 2568/91
Reg. why. 1513/2001
Reg. why. 1234/2007
Reg. why. 640/2008
Reg. UE n. 1348/2013