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Olive Oil The Education
Grades of Olive Oil
All olive oil starts with fruit on a tree. What happens after the fruit and the tree part company makes all the difference to the oil produced. According to the United States Department of Agriculture the only acceptable grade of olive oil is Virgin Olive Oil. The Food and Drug Administration 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.
The two ways to assess extra virgin olive oil, chemical and organoleptic analysis, are equally important even though one is totally objective and the other is totally subjective.
Laboratory analysis can tell us about the levels of beneficial polyphenols and oleic acid, and the products of deterioration, free fatty acids and peroxide. But it cannot tell us anything about the pleasure to be derived from using fresh, well made oil.
Organoleptic analysis happens in the nose and mouth of the taster, either professional or you as the end user. Aesthetic notes of fruity, nutty, fresh grassy, peppery, and many, many others are there in varying balance that provides complexity to the oil and appeal 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. Please allow yourself the opportunity to taste and assess many olive oils to educate your palate and help you find the olive 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. Once again 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 olive oil in many producing countries.
Virgin olive oil is produced by the use of physical means and no chemical treatment. It has an acidity value 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 and virgin olive oil.
Pure olive oil. Oils labeled as “Pure olive oil” or ‘Olive oil” are usually a blend of refined and virgin production oil. 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 chemical and physical filters.
Olive oil is a blend of virgin and refined production oil with an acidity value of no more than 1.5% and lacks a strong flavor.
Olive-pomace oil is refined pomace olive production oil possibly 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 but it is often used for certain kinds of cooking in restaurants.
Refined olive oil is 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.
Lampante oil is not suitable as food because it is made usually from olives that are spoiled or insect infested. The term lampante comes from olive oil’s long-standing use in oil-burning lamps. Lampante oil is mostly used in the industrial market. It must be chemically refined before it can be consumed. The resulting oil, after refining, 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”.
As the United States is not a member, the IOOC retail grades have no legal meaning in this country. As such, terms such as “extra virgin” may be used without legal restrictions.
In the United States, the U.S. Department of Agriculture (USDA) has identified four grades of olive oil based on acidity, absence of defects, odor and flavor:
U.S. Grade A or U.S. Fancy possesses 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 possesses 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 possesses 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 affect the quality of the finished product.
Theoretically, there exists an exact moment when ripeness and acidity levels are at their respective optimums in every olive. Crushing the fruit before this imaginary “moment” or peak of ripeness will translate to 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.
Crushing the fruit before it is ripe does provide one major benefit: the acidity levels are much lower in unripe fruit. Since the primary chemical test for grading olive oil focuses on the acidity level, this early harvest oil is sometimes cynically 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 standard.
Early harvest olive oil can also provide a semblance or note of freshness to oils that are otherwise tired.
Conversely, crushing olives that are overripe will produce olive oil that is smoother and softer in its inherent intensity and sought after fruity characteristics. The practice of letting the fruit become overripe on the tree has the significant economic benefit to the crusher 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 it is refined, one of the main reasons why 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 increases 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 prices between these two drastically different products are virtually nonexistent. The competing interests of yield, acidity level, and flavor profile make when the olive is crushed, the single most important consideration when it comes to producing 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. When either consideration of higher yield or lower acidity level becomes too dominant the cost and quality of the oil suffer. It seems fitting that a balanced approach is the most rewarding one.
Single Variety and Mono Cultivar
The variety or cultivar selected for planting will certainly have an effect on the overall flavor and characteristics of the oil, but the characteristics and relative merits of individual cultivars are hotly contested. Although most table fruit is unsuitable for oil production because of yield, size, and oil content there are always exceptions. It is also notable that many of the attributes ascribed to single varieties disappear when planted in other regions with different soil conditions and microclimates.
This complicated subject is woven happily and inextricably into the unique fabric of the area where each variety is grown negating the attitude that one cultivar is superior to the rest. Variety in olive oil as in all things is indeed the spice of life.
Olive Oil Production
The process of olive oil production
The basic procedure for 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 matt pressing has the drawback of intensive labor and lower yield compared to modern methods. Olives are crushed to paste between by 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 press.
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 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 continues to evolve promising continued improvement in both quality and efficiency.
The continuous method 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 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 on this 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 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 cost 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 Provincial View
When determining the overall quality and relative value of olive oil, where the olive oil is produced tends to be the most overrated and overemphasized variable. Other far more important variables such as ripeness at harvest, span of time between harvest and milling, temperature used for extraction, and storage methods, if not done correctly, render the location of the grove meaningless. Appellation is primarily a marketing device used to create value and status.
Preoccupation with origin has given rise to the current situation where Italy is both the largest importer and exporter of olive oil in the world leading to the widespread practice of claiming exceptional quality and status where none exists.
From the tiny region of Tuscany flows a virtual river of olive oil surpassed in volume only by the biblical miracle of the loaves and the fishes. High quality olive oil can be produced in Tuscany but it will be rare compared to mass produced, commercially blended oils. The best way to understand the relative value of where an olive oil is produced is to blind taste, all in one sitting, many different varieties from many regions. Then one can begin to understand and appreciate several variables that determine the overall quality and value of olive oil.
Argentina, Australia, California, Greece, Spain, Tunisia, Turkey, Syria, and Morocco offer wonderful, unique oils. It is our belief that the unsung oils of the world will one day be as to consumers as coffees or wine varietals. Our advice is to have as many authentic olive oil experiences as possible. There is no substitute for personal experience. If you trust your own educated aesthetic sensibility, there is no right or wrong answer when it comes to your individual preference taste.
Flavor Profile and Big Business
Choosing the right oil
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. The style of marketing olive oil is changing to meet consumer pressure for educated choice, and the opportunity now exists to taste a range extra virgin olive oil, know the crush date and complete chemistry. All are factors influencing choice.
The olive oil season begins in early October in the Northern Hemisphere and April in the Southern Hemisphere extending to late February in the Northern Hemisphere and June in the Southern Hemisphere.
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 producing 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.
There are as many different olive oil flavor profiles as there are olive groves with layers of variables superimposed on layers of sub-variable and any one or combination can have a profound effect on the flavor and overall characteristics of the oil. The highly perishable nature of olive oil which begins to soften the day it is produced and heads steadily down in intensity and brightness which can only be slowed by rapid harvest to milling to storage lends difficulty to the production of uniform, consistent, readily available, high-quality olive oil.
Large multinational corporations have such huge markets to supply that there is no single variety, country, or style capable of supplying 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. Companies requiring such enormous quantities of a single flavor profile have no choice but to mix many different styles and varieties to achieve this end. The battle of quantity versus quality is very much a factor. The inevitable sacrifice of variety and uniqueness to the demands of volume and continuity is unavoidable if the goal is to market olive oil on this massive scale.
Each producing country has a dominant variety or cultivar historically suited to its terrain, and is representative of the general “style” of the country. These styles are often closely contested from region to region within a country. A reasonably experienced taster can pick out the dominant style or cultivar of each of the large producing countries. The dominant cultivars in Spain are the Picual, Hojiblanca, and Arbequina. Italy has Coratina, Tunisia the Chemali, Greece the Koroneiki, and Turkey the Ayvalik. Look for oils by variety as well as region and country. The number of high quality oils available from small regional mills is increasing daily as more consumers and producers are waking up to the fantastic possibilities that exist.
Try as many extra virgin olive oils as you can as they represent extraordinary examples of unique quality impossible to duplicate in the traditional supermarket brands.
Packaging and Re-Packaging Olive Oil
The finest oil, without regard to the care taken during cultivation of the fruit, harvesting, transport, and processing, will suffer degradation if not packaged correctly. Bulk storage, with a low surface area to volume ratio, dark storage sheltered from UV light, and, if possible, nitrogen displacing oxygen in the storage vessel, contribute to maintaining quality, nutritional and anti-oxidant value.
Effective packaging options range from stainless steel tanks to UV protected dark glass bottles. Clear, un-tinted glass bottles can be used for short periods of a week or two, but avoid purchasing oils in un-tinted bottles without packaging dates or displayed on store shelves for indeterminate periods.
Nearly all of the olive oil sold in the United States has traveled by ocean freight from the Mediterranean and may have been in the bottle for months before it makes the thirty-to-sixty-day crossing. It may be months more before the oil makes its way to the retail outlet where it is finally purchased. It is unfortunate that a significant portion of olive oil sold in the United States would fail to pass a grading test if it were retested at the point of sale.
Olive oil is a seasoning as well as a food and should be considered a fresh addition to cuisine. Use and enjoy it at its freshest and best.