What is the Difference Between Olive Oil Grades? How is EVOO made? What do the different grades mean?
The other day, I was trying to figure out what the heck the difference is between extra virgin olive oil and virgin olive oil. Is it a First Press versus a Second Press? Is regular Olive Oil refined and therefore not as good for you? Well, I was wrong on all accounts.
Olive oil produced in Europe has the following classifications applied by the International Olive Council in Europe (IOC) (see Resources below). America has had their own olive oil standards since 1948 that are well below the IOC’s. This has meant that olive oil producers could send us “extra virgin olive oil” that did NOT meet the IOC standards. But that is all going to change in October of 2010, when the US olive oil standards are revised to be in line with the IOC’s standards (see Resources below) .
European Olive Oil Standards (and US Standards as of Oct 2010):
Virgin means the oil was pressed with no chemical treatments involved.
Extra Virgin Olive Oil (EVOO) - This oil is made by pressing olives to extract the oil - no chemical treatments were
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| Extra Virgin Olive Oil |
involved. It must have less that 0.8% acidity and be judged to have superior taste. By the way, if you take a sip of your EVOO, you should feel a tingle at the back of your throat (wait a few seconds for it) -- the tingle is from an anti-inflammatory substance called oleocanthal -- the more tingle you feel, the better your EVOO is!
First Pressed - If the Olive oil says “First Pressed” - now-a-days, it just means pressed rather than extracted from other methods. (In the past, extraction was from olives pressed between mats - the first press was a better quality oil, and the second press would yield oil that needed to be refined.)
Virgin Olive Oil (VOO) - This is not the second press! If the olive oil’s acidity is more than EVOO but less than 2%, and has been judged to have a good taste, then it is classified as VOO.
Olive Oil (OO) - this is usually a blend of refined oil and VOO. See “refined oil” below.
Refined Oil - most poorer quality olives need some form of refinement to remove the strong taste and the high acidity. A process using charcoal to filter the oil is used. Temperatures can be high - reaching up to 470° F, however no solvents are used.
Cold Pressed or Cold Expeller Pressed - regular pressing of olives produces friction which can cause very high temperatures. When olives are “Cold Pressed” - the heat is monitored so as not to be greater than 120° F. These oils retain more nutrients. If the heat is not monitored then the oils were just “Expeller Pressed“.
Organic - This will be the healthiest oil yet as there will not be any pesticides or herbicides used in the growing or processing of the oil.
Olive Pomace Oil - solvents (mostly Hexane) are used to extract oil from the remaining product after virgin oil has been pressed, it may be heated, and then refined This oil has only neutral flavor.
Hexane - Hexane is made from petroleum. It can cause dizziness, and with long-term exposure - nerve damage. The problem with these solvent extracted oils is that some of the solvent remains in the oil. It is also more toxic to the environment when used in the manufacturing process because it is released into the air -- the EPA regulates the emissions of hexane as it contributes to smog problems. (See Resources below)
Lampante Oil - this is NOT suitable for human consumption - its name comes from its olden time use in oil-burning lamps.
Country of Origin Labeling
You should see the country of origin listed on all domestic and imported olive oil. Even OO that has been blended will list the multiple countries of origin on its label. This is because the US has adopted a “country of origin” labeling for all its food on Sept 30, 2008. Also, the IOC ruled that starting in July 2009, all their EVOO and VOO will be labeled stating the of country of origin.
Shelf Life of Olive Oil
Olive oil has a shelf life of 12 to 18 months.
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| generic extra virgin olive oil |
Is It Safe to Cook with Extra Virgin Olive Oil?
Smoke Point of Olive Oil
The smoke point of an oil is the point in frying when you can visibly see smoke rising from the pan. This is not desired as it is changes the flavor and decomposition of the oil occurs releasing free radicals. (Free radicals are unstable molecules which destroy other molecules and are responsible for aging and tissue damage.)
- EVOO has a smoke point from 365-400°F (see Resources below)
- OO has a smoke point of around 200°F
Your stove’s temperatures:
Low Heat = 300° and lower
Medium heat = 325-375° F
High Heat = 400-450° F
Can Cooking with Olive Oil produce Trans-fatty Acids (Trans fats)?
The short answer is NO - Virgin olive oils are highly monounsaturated oils (55-85% of which is Oleic acid) which do not oxidize as fast as polyunsaturated oils, and remain stable (does not go rancid) at high temperatures and do not easily become hydrogenated (creating Trans fats). However, deep frying will hydrogenate olive oil in miniscule amounts - but you will get more amounts if you re-heat it repeatedly, like they do in commercial operations for making French Fries, etc.
Resources:
- International Olive Council (IOC)
- New US Standards for Olive Oil
- Smoke Point of Olive Oil from the Olive Oil Source
- EPA Hexane Rules
- Supermarket Extra Virgin Olive Oils by "Cook's Illustrated"
