Olive oil facts
Types of olive oil
Olive oils fall into many categories, depending on factors such as extraction methods and acidity The International Olive Council (IOC), an intergovernmental organisation that officially governs about 95% of global olive oil production, classifies olive oil as follows:
- Extra virgin olive oil: Extracted using exclusively mechanical methods within 24 hours of harvesting to avoid fermentation. During the whole process, the temperature cannot exceed 27°C. Further, the free acidity of the oil may not exceed 0.8%. There should be no defined sensory defects. As well as chemical quality control, extra virgin olive oil must also pass a rigorous testing by a panel of experts who evaluate its organoleptic properties. Extra virgin olive oil is the highest-quality olive oil on the market.
- Virgin olive oil: Also extracted solely by mechanical means. The upper limit of free acidity is 2% and there can be some sensory defects. However, the oil must still be judged to have a good taste.
- Lampante olive oil: While this type of olive oil is also extracted using mechanical methods, it is not for human consumption; in the past, it was used in oil lamps.
- Refined olive oil: Obtained by refining lampante oils using physical and chemical methods. While the free acidity is less than 0.3%, this type of oil cannot be sold to consumers.
- Olive oil: Obtained by mixing refined olive oil and virgin olive oil, resulting in a free acidity of less than 1%.
- Crude olive pomace oil: Extracted, using a solvent, from pomace, the residue of the olives left after the mechanical extraction of olive oil. This type of oil cannot be sold to consumers.
- Refined olive pomace oil: Obtained by refining crude olive pomace oil by physical and chemical methods, resulting in a free acidity of less than 0.3%. This type of oil cannot be sold for consumption.
- Olive pomace oil: Obtained by mixing virgin olive oil and refined olive pomace oil. This type of oil has a free acidity of less than 1% and is fit for consumption. However, it cannot be described as olive oil. While it has a neutral taste and is not favoured by aficionados, it does have the same oil composition as regular olive oil and a relatively high smoking point, making it usable for cooking.
Storing your olive oil
While extra virgin olive oil is relatively resistant to oxidation, thanks to the fact it is rich in antioxidants, prolonged exposure to light, heat and oxygen can affect the quality of the oil.
Consequently, always store your olive oil in a place protected from direct sunlight and heat – in fact, the ideal temperature for storing olive oil is between 12°C and 18°C. The best containers are dark-coloured glass bottles – glass does not affect the taste of the oil and is recyclable – or stainless steel containers. The container’s cap must also be airtight. Never store you oil in a transparent glass jar without a sealing cap unless it is for immediate consumption.
Extra virgin olive oil should be consumed within 18 months of the bottling date.
According to EU Regulation 1169/2011, an extra virgin olive oil label must possess the following information:
- Net quantity
- Best before date
- Conditions of storage and use
- Place of origin
- Nutritional values
In addition, the label may have additional information:
- Cold pressed or cold extraction: The temperature of the oil has not exceeded a certain temperature during the extraction process – for extra virgin, the limit is typically considered to be 27°C (80°F), although there is, in fact, no reliable international standard that everybody follows. In Europe, however, EU regulations only allow oils extracted in conditions where the temperature did not exceed 27°C to use the term cold extraction. Moreover, in Europe, the term cold extraction means that the extraction process has used centrifugal force, while the term cold pressed means that the pressing was entirely physical. Outside Europe, this distinction is not applicable.
- First cold: The oil has been extracted during the very first pressing of the olives (first) and temperature has not exceeded a certain limit during the process (cold). In effect, cold in this case does not mean no heat whatsoever, as it does in some parts of Italy. During the harvesting season, the temperature is so low that extracting oil would not be efficient without some heat – the point is not to exceed a certain temperature so as not to alter its flavour and healthy properties.
- While the label may indicate where the oil was bottled or packed, this does not guarantee that it was produced in the same country – the oil may originally be from another country or a mixture of oils from more than one country.
- Often, high quality extra virgin olive oils indicate the acidity, although this is not required. The lower the acidity, the more likely it is to be proudly displayed.