Different Types of Olive Oil and Canola

Extra Virgin Olive Oil or EVOO

  • Virgin olive oil which has a free acidity, expressed as oleic acid, of not more than 0.8 grams per 100 grams (0.8%), and the other characteristics which correspond to those fixed for this category. Extra Virgin Olive Oil is Expeller Pressed. See definition below.
  • Extra Virgin olive oil accounts for less than 10% of oil in many producing countries. Used on salads, added at the table to soups and stews and for dipping.
  • It the most expensive and highest in quality, with excellent flavor and aroma, and is best used as a condiment for dressing foods and salads or as a dipping oil.
  • Although it can be used for baking, it is best not to heat this fine oil, as its high quality flavors will dissipate.

Definition of Expeller Press
Expeller, First Press or Cold Pressing is a mechanical method for extracting oil from raw materials. The raw materials are squeezed under high pressure in a single step. When used for the extraction of food oils, typical raw materials are nuts, seeds and algae, which are supplied to the press in a continuous feed. Expeller Pressed oils are arguably the best for human consumption.

Virgin Olive Oil

  • This oil is obtained only from the olive, the fruit of the olive tree, using only mechanical or other physical means in conditions, particularly thermal conditions, which do not alter the oil in any way.
  • It has not undergone any treatment other than washing, decanting, centrifuging and filtering. It excludes oils obtained by the use of solvents or re-esterification methods, and those mixed with oils from other sources.
  • It can be qualified as a natural product, and virgin olive oil can have a designation of origin when it meets the specific characteristics associated with a particular region.
  • Virgin olive oils can have the following designations and classifications depending on their organoleptic (taste and aroma) and analytic characteristics (the degree of acidity refers to the proportion of free fatty acids, not to the taste).

Pure Olive Oil or 100% Olive Oil or Olive Oil

  • A labeling that indicates only that the contents are 100% olive oil, i.e. that no other types of oil have been added; it does not indicate quality.
  • It can be a blend of refined oil and virgin or extra virgin olive oil and is considered to be minimally processed.

Refined Olive Oil

  • The IOOC describes Refined olive oil as the olive oil obtained from virgin olive oils by refining methods which do not lead to alterations in the initial glyceridic structure.
  • It has a free acidity, expressed as oleic acid, of not more than 0.3 grams per 100 grams (0.3%) and its other characteristics correspond to those fixed for this category in this standard.
  • This is obtained by refining virgin olive oils which have a high acidity level and/or organoleptic defects which are eliminated after refining.
  • Over 50% of the oil produced in the Mediterranean area is of such poor quality that it must be refined to produce an edible product.

Note that no solvents have been used to extract the oil but it has been refined with the use of charcoal and other chemical and physical filters.
An obsolete equivalent is “pure olive oil.”

Pomace Olive Oil

  • As per the IOOC definition: Pomace is the ground flesh and pits after pressing.  Olive-pomace oil is the oil obtained by treating olive pomace with solvents or other physical treatments, to the exclusion of oils obtained by re-etherification processes and of any mixture with oils of other kinds.
  • Olive-pomace oil is the oil comprising the blend of refined olive-pomace oil and virgin olive oils fit for consumption as they are. It has a free acidity of not more than 1 gram per 100 grams and its other characteristics correspond to those fixed for this category in this standard.

In no case shall this blend be called “olive oil.” It is considered an inferior grade and is used for soap making or industrial purposes.

Infused Oil

  • Infusion is a method of flavor enhancement that adds the flavor of herbs or fruits into olive oil.
  • It differs from the more arduous artisan method of steeping the herbs/fruits in the oil and then removing them.

Flavored Olive Oil

  • Flavored extra virgin olive oils are manufactured by adding ingredients to the olives as they are being pressed.
  • Lower quality grades of olive oil are enhanced only after the oil has been produced. A heat treating process is used to infuse the oil with flavoring agents.
  • Citrus extracts and citrus zest, such as the lemon zest in the olive oil above, are popular additions; as are garlic, basil, rosemary, peppercorns, and chipotle.

NOTE: It is not safe to prepare homemade flavored olive oils unless they will be used immediately. Homemade flavored oils may promote bacterial growth that can cause illness. Commercial processes eliminate harmful bacterial growth.

Technically, olive oil which has had herbs or fruits infused in it cannot be called olive oil. According to IOOC regulations it must be called “fruit juice.” In reality, few producers comply with this labels their products “lemon infused olive oil” or “basil olive oil.”  Because of their immense popularity, the California Olive Oil Council is trying to come up with a meaningful labeling standard for flavored oils.

Canola Oil

Canola, bred naturally from the Rapeseed, was developed at the University of Manitoba. Thus came the name “Canadian oil, low acid”. Canola oil is made at the processing facility by slightly heating and then crushing the seed. Almost all commercial grade canola oil is then refined using hexane. Finally, the crude oil is refined using water precipitation and organic acid, “bleaching” with clay, and deodorizing using steam distillation. Much of today’s canola oil is genetically modified (GMO) to resist disease and drought. Canola oil is a rich source of vitamin E, an important dietary antioxidant. Canola oil also contains the lowest amount of total saturated fat of commonly consumed vegetable oils and is second only to olive oil in the levels of the important monounsaturated fat, oleic acid.

Health Claims

The FDA allows olive oil manufacturers to place a health claim on bottles linking olive oil to reduced risk of coronary heart disease. Olive oil controls LDL (“bad”) cholesterol levels while raising HDL (“good” cholesterol) levels. Continuing research indicates there may be other benefits as well, from the redistribution of body fat to painkilling properties, but these have not yet received FDA sanction.

The International Olive Oil Council (IOOC) determines standards for grades of olive oil for most of the world.

More on the Acidity of Olives

The natural acid in olives is oleic acid. The most interesting facts are:
If the acidity of the cold-pressed oil is less than 1%, it is known as extra virgin olive oil.
If the acidity is between 1% and 3.3%, the oil is called virgin olive oil.
Any oil obtained from the first cold pressing that has a natural acidity above 3.3% cannot be sold as virgin olive oil. It is usually sent to a refinery to reduce the acidity and eliminate any other objectionable qualities in aroma and flavor, and is sold as “olive oil” or “pure olive oil,” a refined product.

The olives are taken to the plant for processing on the same day if possible. While more oil is in the olive the darker it becomes, acidity increases at the same time; so the grower has to decide to pick exactly at the right time to maximize the oil while minimizing the acidity (the lower the acidity, the higher the grade of oil and the price it commands).