The most important thing to know about olive oil is that it is a naturally produced food product which is readily damaged by heat, light, and mechanical action. While producers need to worry about mechanical action to protect and preserve this natural product, consumers should always strive to avoid exposing oil to heat and light. When oil is not properly cared for, it becomes rancid, or inedible.
|MOST COMMONLY ASKED QUESTIONS:|
|Q. What does "Extra Virgin" mean?|
|Q. What is "Cold Pressed?"|
|Q. How long can olive oil be kept?|
|Q. Where should olive oil be stored?|
|Q. How can quality be assured?|
The terms "pure", "virgin", and "extra virgin" refer to the chemical properties of olive oil. Olive oil is made up of large complex organic molecules which can be readily damaged by heat, light, or mechanical action. This damage causes fragments of the oil molecule to break off. These molecular fragments are known chemically as fatty acids. One fatty acid in particular, oleic acid, is commonly formed when olive oil is damaged. The human body prefers to digest undamaged oil molecules (our body's digestive enzymes work best on undamaged molecules). Thus, we have a strong preference for virgin oil molecules, namely unbroken ones.
When an oil has a high percentage of broken oil molecules, it becomes hard to digest (sometimes passing right on through!). These kinds of damaged oils are termed rancid. Thus, rancidity in olive oil (or any edible oil) is the result of a chemical breakdown, not the result of a microbial spoilage as is common with other foods.
By measuring the percentage of fatty acids in an oil, the presence of damaged oil molecules can be gauged. So, the lower the level of fatty acid, the more virgin, or unbroken, are the molecules in a particular oil.
Thus, the presence of 3 percent or less of oleic fatty acid means "pure"; "virgin" means 2 percent or less; and "extra virgin" means .8 percent or less under the standards of the International Olive Oil Council.
The very best olive oils in the world have fatty acid levels (not to be confused with pH!) of about .25 to .33 percent - or about one half to one third lower than the .8 percent international standard for extra virgin olive oil. At Long Meadow Ranch we routinely produce oils with fatty acid levels below .20 percent and have produced oils as low as .05 percent.
"Cold pressed" had its origins in an earlier traditional method of processing olive oil. The olives were crushed (generally on a stone crusher) and then pressed using a large basket press.The crushed olive paste was laid in layers on mats and then pressed to extract the oil and water. This is a "cold" process, as no heat is added. The left over solid material on the basket press mats is called sansa (akin to pomace from a wine press).
Because this sansa contains some residual oil, water can be mixed with the sansa and then heated to extract some of the remaining residual oil by putting it through the basket press again. This process is highly inefficient because the yields are low and energy must be used to heat the mixture. Nevertheless, these oils were neither "first pressed" nor "cold pressed" and the terms became commonly used, singly or together, to connote oil made from the first pressing. Very little oil is made in this heated second-pressing fashion anywhere in the world today. (If oil is extracted from sansa employing heat, a distillation-like process is generally used and the resulting oil is commonly labeled "pomace oil.")
Furthermore, only a very small percentage of olive oil is made using a basket press system. Most oils today are "pressed" using a horizontal decanter which extracts the oil using a centrifugal method that is highly efficient and helps protect the oil by not exposing it to uneven levels of pressure found in basket presses or to potentially contaminating mats. Thus, oil is not "pressed" at all in most production systems.
Further confusing this issue is the fact that, in a modern processing facility, crushed olive paste is generally heated to temperatures ranging from 70 to 115 degrees Fahrenheit prior to the paste being passed through horizontal decanters. The higher ranges of temperature are employed to increase the oil yield (more gallons) from the paste even though olive oil is damaged at temperatures above about 86 degrees F. There is no accepted industry standard for describing the level of heat applied at this stage to be "cold". (Of course, as described above, "pressed" has no meaning either.) Nevertheless, because there are no governmental labeling standards and these historical terms are thought to denote quality in the minds of consumers, the terms "cold pressed" and "first cold pressed" are still commonly used. The terms have no practical meaning to a consumer.
Long Meadow Ranch does not any longer use the term "cold pressed." (We process our oil at temperatures of approximately 78 degrees F to ensure the highest possible quality - a practice that we believe places us among the lowest temperature producers in the world.)
Olive oil is generally best within the year in which it was made. While some oils have been successfully stored for much longer, there is no advantage, unlike wine, to aging olive oil. If a bottle is opened and exposed to air, it will likely last only about 60 days before deteriorating (becoming rancid) - especially if it is also exposed to light. Hint: if you are using one of your prized olive oils slowly, try rebottling into small bottles (filled to the top) and place it in a cool dark location.
Let's start with where not to store olive oil. On display over the stove is a very bad idea (unless you are using it very quickly) because of its exposure to heat and light. Olive oil should never be stored in a refrigerator as the low temperature can cause the oil to solidify or for certain natural waxes and other compounds found in the oil to precipitate and form "pearls" and other solids in the bottom of the bottle. These components, once out of solution, will reduce the flavor and consistency of the oil. Reheating to put them back into solution is also harmful to the oil.
Do not store your olive oil in the kitchen cabinet above the counter next to your stove. This is the most common mistake. In most kitchens the upper cabinets contain lighting fixtures on the underside to light the kitchen countertop area. The great temptation is to place your prized bottle on the bottom shelf of the upper cabinet - right over the light fixture which promptly heats the olive oil!
The best place for your oil is either conveniently below the countertop to left or right of your stove, or safely in a dark, cool pantry. A wine cellar is sometimes used but this is really not necessary, and may tempt one to think that oil improves with age, which it does not.
Q. How can quality be assured?
A. Look for the COOC seal.
Much to the surprise of many American consumers, there are no regulatory restrictions on what can be placed on a bottle of olive oil. Producers can make claims and use terms such as "cold pressed" or "extra virgin" without being subject to any government review or oversight. Furthermore, oil is not regulated with regard to its origin. So, oil produced in one location and packed or bottled in another can be labeled as the producer chooses, which helps explain how so much "Italian" olive oil is imported into the country. There are regulations requiring a bottle labeled "olive oil", to actually contain olive oil. But, sadly, there is a long history of adulteration of olive oils through the addition of low cost flavorless oils made from corn and other grains. Government enforcement of these "food purity" standards is rare.
The United States is not a member of the International Olive Oil Council which sets worldwide standards with regard to quality and country of origin. Olive oil produced in the EU is subject to rigorous standards, including chemical testing to establish the level of virginity and tasting by a master panel to warrant that olive oil labeled extra virgin is without flaws. Ironically, one safeguard for an American consumer is to purchase olive oil intended to be sold in the EU.
If purchasing oil produced in the United States, one must look for a COOC certification seal to have any assurance of label integrity. The California Olive Oil Council (COOC) , a voluntary industry association, administers a certification program which requires an oil be (1) chemically tested to meet virginity standards (oleic acid less than .5 percent oleic acid, which is lower than the international standard of .8 percent), (2) tasted by a master panel trained and certified by the International Olive Oil Council, and (3) labeled accurately with regard to its origin in order to receive the COOC certification seal. All Long Meadow Ranch olive oils display this seal. Of course, whether an oil originates in the United States, or elsewhere, the only true assurance a buyer can have is the integrity of the producer.
The ultimate quality of olive oil is highly sensitive to olive handling - especially the length of time from harvest to pressing. Unlike few facilities outside of Tuscany, we can process small lots of olives on our own Ranch within two hours of picking. And, with the Pieralisi system and our custom designed facility, we employ the world's best methods for low temperature processing while maintaining the highest standards of cleanliness.