Olive oil starts with fruit on a tree. What happens after the fruit and the tree part company makes all the difference to the end product.
According to the United States Department of Agriculture (USDA), the only acceptable grade of olive oil is Virgin Olive Oil. The Food and Drug Administration’s (FDA) definition is,” Olive Oil is the edible oil expressed from the sound, mature fruit of the olive tree.” No recognition is given to refined or extracted oil.
There are two ways to assess Virgin Olive Oil:
One is objective, CHEMICAL, done in a laboratory and used to find out the levels of polyphenols, oleic acid, free fatty acids and peroxide present in the product. This method cannot tell us anything about the pleasure derived from using fresh, well made, olive oil.
The other way is subjective, ORGANOLEPTIC, and happens on the nose and mouth of the taster, either professional or you, the end user. Aesthetic notes of fruits, nuts, fresh grass, flowers, pepper, and many, many others, are there in varying balance, giving complexity to the oil and appealing to each person in different ways.
Laboratory analysis can track down the chemical nature of those flavors and aromas, but the human sensory system is still the best organoleptic analysis device.
We recommend that you give yourself the opportunity to taste and assess many olive oils, to educate your palate and help you find the oil that gives you the most satisfaction.
Most grading is based on the method of production and designations are a marketing tool used by producers. The terms can be confusing and, sometimes, intentionally misleading. It is important to know as much as possible about what you choose.
Extra-Virgin Olive Oil comes from virgin oil production only, contains no more than 0.8% acidity, and is judged to have a superior taste. Extra Virgin Olive Oil accounts for less than 10% of oil in many producing countries.
Virgin Olive Oil is produced by the use of physical means and no chemical treatment. It has an acidity of less than 2%, and is judged to have a good taste.
After these two grades come the blends of oil that are mainly (up to 90%) refined oil mixed with virgin olive oil.
Oils labeled as Pure Olive Oil or Olive Oil are usually a blend of refined and virgin olive oils. 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. No solvents are used to extract the oil, but it has been refined with the use of charcoal and other chemicals and physical filters.
Olive oil is a blend of virgin and refined olive oil, with no more than 1.5% acidity, and lacks a strong flavor.
Olive-Pomace Oil comes from the pulp or “pomace” left after the first extraction of the oil. Chemical solvents and heat are used in the process. It should not be labeled as olive oil.
Refined Olive Oil is obtained from virgin olive oils with high acidity levels and/or organoleptic defects (eliminated after refining). The methods used do not alter its initial glyceridic structure. It has a free acidity, expressed as oleic acid, of not more than 0.3 grams per 100 grams (0.3%). No solvents are used to extract the oil, but it has been treated with charcoal and chemical and physical filters. It is generally tasteless, odorless, and colorless. An obsolete equivalent is “pure olive oil”.
Pomace Olive Oil is extracted from the ground flesh and pits of the olives after having being pressed. Chemical solvents, mostly hexane, and heat is used in the process. Sometimes blended with some virgin production oil, it is fit for consumption, but may not be described simply as olive oil. Olive-Pomace Oil is rarely sold at retail. It is often used for certain kinds of cooking in restaurants, soap making or industrial purposes.
Lampante Oil is not edible because it comes from bad fruit or careless processing. The term lampante comes from olive oil’s long-standing use in oil-burning lamps. It is mostly used in the industrial market. It must be chemically refined before it can be consumed. The resulting oil is known as A-Refined, or Refined-A olive oil. It is not, strictly speaking, “olive oil.” It is used as the primary ingredient for a new product that is sold as “Pure Olive Oil”.
Please take note of this: the United States is not a member of the IOOC (International Olive Oil Council), and retail grades have no legal meaning in this country. Terms such as “extra virgin” may be used without legal restrictions.
Since 1948 the U.S. Department of Agriculture (USDA) has listed four grades of olive oil based on acidity, absence of defects, odor and flavor:
U.S. Grade A or U.S. Fancy features a free fatty acid content of not more than 1.4% and is “free from defects”.
U.S. Grade B or U.S. Choice possesses a free fatty acid content of not more than 2.5% and is “reasonably free from defects”.
U.S. Grade C or U.S. Standard holds a free fatty acid content of not more than 3.0% and is “fairly free from defects”.
U.S. Grade D or U.S. Substandard has a free fatty acid content greater than 3.0% and “fails to meet the requirements of U.S. Grade C”.
With these diverse labeling styles and the small amount of information they provide, the best indicator of a good olive oil is obtained by tasting while keeping in mind the freshness and beneficial nutritional and antioxidant levels.
Timing is Everything
The most critical decision and least understood variable in producing fine olive oil is the level of ripeness of the fruit when the olives are harvested, affecting both yield and organoleptic characteristics. Additional factors of regional variations, harvest time, risk of frost, and mill schedules also affect the quality of the finished product.
Theoretically, there exists an exact moment when ripeness and acidity levels are at their respective optimum in every olive. Crushing the fruit before this “moment” or peak of ripeness will translate into a lower yield and greener tasting oil. “Grassy” or greener tasting oil is the result of higher levels of chlorophyll still held in the fruit. This provides one major benefit: the acidity level is much lower. Since the primary chemical test for grading olive oil focuses on the acidity level, this early harvest oil is referred to as the “virgin maker.” The lower yield, and bitter tasting aspects resulting from crushing olives before they are ripe can be offset by using this oil as a blending agent that serves to lower the acidity levels of oils that might not otherwise meet the chemical standards. Early harvest olive oil can also provide a semblance or note of freshness to oils that are, otherwise, tired.
On the other side, crushing olives that are past their best, will produce olive oil that is smoother and softer in its inherent intensity, and sought after its fruity characteristics. The practice of the crusher of letting the fruit become overripe on the tree has the significant economic benefit of increasing the overall ratio and yield of oil to olive by weight. This, of course, lowers the cost of the oil in a big way. The acidity level (free fatty acids or FFA’s) rises as the fruit begins to decompose, increasing, until it is unfit for human consumption until refined (one of the main reasons there is so much refined olive oil produced).
Farmers who let their olives become overripe on the tree are rewarded economically by a very high yield. The difference in yield from early harvest oil (12% to 16% oil to olives) and late harvest yield (20% to 28%) is significant, and increments in yield between 33% and 133% can be achieved.
Today, the world market price that separates refined olive oil from extra virgin olive oil is less than 12%. There are times when the price between these two drastically different products is virtually nonexistent.
WHEN the olive is crushed, is the most important consideration to produce high quality extra virgin olive oil.
If the fruit is crushed before it is ripe it will be excessively expensive and the oil will have a bitter, less fruity, chlorophyll taste. If the fruit is allowed to become too ripe, then it will be unfit for consumption unless it is first refined. It seems fitting that a balanced approach is the most rewarding one.
The Process of Olive Oil Production
The basic procedure making olive oil has remained the same for thousands of years: harvest the olives at the right time, crush them into paste, separate the solids from the liquid components, and further separate the vegetable water from oil. The method of extraction has a distinct effect on the flavor and ultimate quality of the olive oil. The mechanical process has undergone numerous changes and refinements that have increased both productivity and quality.
The archaic, but still used, method of stone grinding and mat pressing has the drawback of intensive labor and lower yield, compared to modern methods where olives are crushed to paste between revolving millstones. The paste is spread on woven mats, stacked in a press and squeezed until the fluid component is recovered in basins underneath.
The vegetable water sinks and the oil is skimmed off the top. The mats are emptied of the pits and skins and “re-buttered” with fresh olive paste to repeat the process. This method results in very sweet oil with slightly higher levels of acidity. The mats impart a distinct flavor, from the cultures that grow in them, with their repeated use. Many old timers insist that this flavor is an absolute necessity to make fine olive oil but considered a defect by proponents of the modern method, proving once again that beauty is in the eye of the beholder.
The machinery and technique of olive oil extraction keeps on evolving, promising continued improvement in both quality and efficiency.
The Continuous Method.- This is the most widespread method used in the world today. Olives enter the mill at one end and oil comes out the other. The olives are crushed by hammer mill and the paste is pumped to a malaxer (mixer) where it is warmed and mixed until the oil begins to separate. The resulting paste is pumped to a centrifuge where the solids are separated from the liquids and the vegetable water and oil are further separated in a final centrifugal process.
There are many variations of the basic theme that involve less heat and less washing of the oil. Because the polyphenols that account for the flavor in olive oil are much more soluble in water than in oil, reducing contact with water preserves the flavor of the oil.
The Integral Method.- It is virtually identical to the continuous method, with the notable difference that the olive stones are removed from the flesh before the oil and water are extracted. This method has existed for thousands of years but the cost and time to manually remove the stones prior to extraction were prohibitive. In addition, there is a slight loss in yield. Proponents of the Integral Method produce less bitter oil with fewer toxins and waxes as well as the added economic advantage of ending up with four valuable and marketable products instead of one: highest quality extra virgin olive oil, highly nutritious olive water, dry olive flesh for all-vegetable cattle feed, and inedible oil-bearing stones for fuel. The benefit of eliminating environmental degradation from large amounts of processing waste is significant.
The style of marketing olive oil is changing to meet consumer pressure for educated choices, and the opportunity now exists to taste a range of extra virgin olive oil, know the crush date and complete chemistry. All are factors influencing choice.
It is difficult to compare taste unless you have the opportunity to open several containers of oil at the same time, not something a consumer usually does.
In the Northern Hemisphere, the oil season begins in early October, extending to late February; in the Southern Hemisphere, it begins in April extending to June.
Over ninety-five percent of the production takes place in the very broad geographic region known as the Mediterranean basin: a large area that extends from Syria in the east, to Spain and Morocco in the west.
Spain is, by far, the world’s largest producer of olives and olive oil. Each producing country has different regions, varieties and preferences for harvest time and style. No two seasons, in any area, are identical. Many varieties alternate in productivity. A year of high productivity is followed by a year of rest.
It is not easy to produce uniform, consistent, ready available, quality olive oil, given the fact that it begins to soften the day it is produced, and heads steadily down in intensity and brightness. Its highly perishable nature can only be slowed by rapid harvest-to milling-to storage.
Large multinational corporations like Unilever (Bertolli), Hormel (Carapelli), Borgess (Star), Nestle (Sasso), and Monini, have such huge markets to supply, that there is no single variety, country, or style, capable of providing the virtual river of olive oil that is required. “Produced in Italy”, a tired marketing ploy, is an attempt to convince consumers that the product they purchase is consistent and uniform year to year.
There is no substitute for individual experience. Try as many extra virgin olive oils as you can; they represent extraordinary examples of unique quality and value impossible to duplicate in the traditional supermarket brands.