What is Extra Virgin Olive Oil?
Extra virgin (EV) olive oil is the oil extracted from fresh olives using a mechanical process without the use of excessive heat or any form of additives or solvents. Provided that the olives are free from disease and they are processed into oil without delay using a clean mill they should produce an olive oil that has an aroma and flavour that is free of taste defects and as such is of extra virgin grade. It should be noted that EV oils can be legitimately made without using a press. In fact most EV olive oils made in commercial relevant quantities are not made by pressing but instead by centrifugation of the paste made by crushing olives. What pressing and centrifugation have in common is that they are both mechanical processes and neither involves the use of any chemical agents. The heat bit is more of a technical issue. You can extract more oil out of olive paste if you heat it up. However, the quality of the oil will suffer as a result. The application of some heat is necessary in order to extract commercially viable amounts of oil with good aroma and flavour. 28-30 degrees Celsius is the ideal with 32 degrees Celsius being the upper end of the temperature range used by most producers interested in quality.
What is the difference between Extra virgin olive and those labeled “pure” , “light” or simpley “olive oil”?
Extra virgin olive oil is essentially the naturally extracted juice from fresh olives. The olives are crushed into a paste, and the oil is physically extracted from this paste without the use of chemicals or excessive heat. Extra virgin olive oil has a distinctive olive fruity aroma and flavour and it contains natural antioxidants. The aroma and flavour, of olive oil adds complementary flavours to a wide variety of dishes. ‘Pure’ and ‘light’ and those labeled „olive oil‟ are olive oils that have been refined. Refining is a complex process that involves the use of acids, alkalis, steam and other agents. The refining process removes all of the aroma and flavour substances out of olive including its natural antioxidants. Artificial antioxidants such as butylated hydroxyanisole (BHA) and the related compound butylated hydroxytoluene (BHT) need to be added back to give the refined olive oil a reasonable shelf life. As such, unlike extra virgin olive oil, „Pure‟ and „Lite‟ olive oil lack the aroma, flavour and any form of bitterness and pepperyness. In fact the word „light‟ only refers to the light colour, aroma and flavour of these oils.
Does the colour of the olive oil say anything about its quality?
Not quality, but it can tell you other things. The colour of an olive oil is related to the amount of chlorophyll it contains. Olives are picked early in the season tend to make green coloured oil as they contain higher levels of chlorophyll. Olives harvested late in the season will typically produce more golden coloured oils due to a higher level of natural occurring levels of carotene like substances. Both oils may be technically equivalent in quality but very different in style. There are also many examples of green coloured oils that taste remarkably ripe, and golden oils that have strong grassy herbal characters. To make matters more complex, many strongly green coloured oils will turn a more golden colour when stored. So don‟t place too much emphasis on colour. Incidentally if you purchase a very green looking oil make sure that it is stored in a dark bottle in a dark place. The stuff that makes it green (chlorophyll) helps start the reaction that makes oils rancid, but only in the presence of light. That makes Amalthea extra virgin olive oil special, you can easy see the diference before even taste it!
Is it true that “light” olive oil contains fewer calories than extra virgin oil?
Absolutely not. All olive oils (and indeed all edible oils) have almost identical energy values. The word „light‟ is made in the context of them having light aroma, flavour and colour.