Olive Oil Grades

Extra - Virgin Olive Oil

To qualify for the label "extra-virgin", an olive oil must conform to four criteria:

• it must be made from the adopted standards of extraction of olives, 
• must be extracted using temperatures not exciding 75F,
• must exhibit an acidity level of less than 0.8 percent (California 0.5), and
• must be free of defects. 

The taste standard has been created by the International Olive Oil Council. 

Olive Oil

Previously called pure olive oil or 100 percent pure olive oil, olive oil is the most widely marketed grade of olive oil and generally costs less than extra-virgin olive oil.  It is combination of extra-virgin olive oils and refined oils,

Lite Oil

Contain only a minute proportion, if any, of extra virgin olive oils.  They are pure rectified oils. 

Pomace Oil

The lowest grade of an olive-based oil is pomace oil.  It is a blend of virgin oil and refined pomace oil, the latter obtained by using solvents to extract the residual oil left in olive paste after making virgin oil.

How to Find Extra Virgin Olive Oil 

To evaluate and rocognize a good olive oil is not easy.  In addition to the parameters involved in the taste (so-called organoleptic characteristics based on Panel Test), there are some chemical parameters (acidity, peroxide number, UV light absorption), which, considered jointly, help to determine the quality of the product.

• Acidity 

  What is acidity? It is considered a key indicator of quality of olive oil and indicates the amount of oleic acid present in given oil.  The quality is inversely proportional to the amount of oleic acid which can be found in the oil: a high proportion means a low quality, a low value indicates a very high quality.

• Peroxides Number

Peroxides are the derivative of the action of enzyme on fatty acids, favored by the presence of oxygen dissolved in oil.  It is the handling of the olives or of the product at various stages that alters the normal composition of the oil: injuries of the pulp of olives, prolonged contact with oxygen (and therefore the duration of its exposure to air), wrong handling during harvest, transport and processing, incorect storage of raw material or final product.

• Ultraviolet Light

Absorption of ultraviolet light: a particular obscure parameter for assessing the quality of oil that can be verified only in a laboratory, using an instrument alled a spectrophotometer. During a test of absorption of ultraviolet light, the oil is passed under a kind of light which has the characteristics of having a particular wavelength, ultraviolet precisely, and we measure the greater or lesser capacity of the oil to absorb it.  The more the oil was produced and stored under optimum conditions, the more the result of the test will be low.  The more, on the contrary, it has been, for example, in contact with oxygen, the more this value will tend to increase, due to oxidation, of some components of the oil that literally decompose peroxides, giving rise to the unpleasant sensory component called 'rancid flavor'.

•  Defects of (Extra Virgin)

• Vegetable water; the term itself indicates an unpleasant aroma of the oil that, unfortunately, has acquired for a faulty or prolonged contact with vegetable water, 
• Agro /Winey/ ; the oil remembers the flavor or the aroma of wine or vinegar, because of the formation of acetic acid, ethyl acetate or ethanol is higher than what would be normal,
• Rancid; due to a common process of oxidation resulting from contact with air, the oil takes on an unpleasant aroma,
• Musty; the olives, because of bad storage conditions, can generate mushrooms and/or yeast that can also transfer their unpleasant aroma an flavor to the final product,
• Sour,
• Metallic,
• Slud  ge,

• Positive Attributes

• Bitter
• Artichoke
• Full-bodied
• Pasty
• Pungent
• Sweet
• Almond
• Apple
• Fruity
• Flowers
• Round
• Green Grass
• Green Leaf

Olive Oil in California

It began in the mid-1700s, when Spanish Jesuits brought the Mediterranean fruit to Mexico.  Toward the end of that century, Franciscan padres from Mexico established the California mission at San Diego de Alcala, where they probably planted the first olive cuttings or seeds.  The first oil was most likely pressed at the missions around 1800.

There were a mere 500 trees in California in 1885: 5,600 in 1876: and half a million at the turn of the century.  Nowadays we don't count trees, we count acres, so an exact comparison is impossible.  There are, however, about 65,000 acres devoted to olive trees alone.  Many of these trees are hundred-year-old Missions, Manzanillos, and Sevillanos, whole orchards that have been brought back with careful attention.

In recant years extra high density orchards have been introduced in California with 600 to 650 trees per acre.  Varieties that are grown in that method are Arbequina, Arbosana and Korneiki.