Olive oil
Encyclopedia
Olive oil is an oil obtained from the olive (Olea europaea; family Oleaceae
Oleaceae
Oleaceae are a family containing 24 extant genera and around 600 species of mesophytic shrubs, trees and occasionally vines. As shrubs, members of this family may be twine climbers, or scramblers.-Leaves:...

), a traditional tree crop
Crop
Crop may refer to:* Crop, a plant grown and harvested for agricultural use* Crop , part of the alimentary tract of some animals* Crop , a modified whip used in horseback riding or disciplining humans...

 of the Mediterranean Basin
Mediterranean Basin
In biogeography, the Mediterranean Basin refers to the lands around the Mediterranean Sea that have a Mediterranean climate, with mild, rainy winters and hot, dry summers, which supports characteristic Mediterranean forests, woodlands, and scrub vegetation...

. It is commonly used in cooking
Cooking
Cooking is the process of preparing food by use of heat. Cooking techniques and ingredients vary widely across the world, reflecting unique environmental, economic, and cultural traditions. Cooks themselves also vary widely in skill and training...

, cosmetics
Cosmetics
Cosmetics are substances used to enhance the appearance or odor of the human body. Cosmetics include skin-care creams, lotions, powders, perfumes, lipsticks, fingernail and toe nail polish, eye and facial makeup, towelettes, permanent waves, colored contact lenses, hair colors, hair sprays and...

, pharmaceuticals, and soap
Soap
In chemistry, soap is a salt of a fatty acid.IUPAC. "" Compendium of Chemical Terminology, 2nd ed. . Compiled by A. D. McNaught and A. Wilkinson. Blackwell Scientific Publications, Oxford . XML on-line corrected version: created by M. Nic, J. Jirat, B. Kosata; updates compiled by A. Jenkins. ISBN...

s and as a fuel
Fuel
Fuel is any material that stores energy that can later be extracted to perform mechanical work in a controlled manner. Most fuels used by humans undergo combustion, a redox reaction in which a combustible substance releases energy after it ignites and reacts with the oxygen in the air...

 for traditional oil lamp
Oil lamp
An oil lamp is an object used to produce light continuously for a period of time using an oil-based fuel source. The use of oil lamps began thousands of years ago and is continued to this day....

s. Olive oil is used throughout the world, but especially in the Mediterranean countries.

History

The olive tree is native to the Mediterranean basin; wild olives were collected by Neolithic
Neolithic
The Neolithic Age, Era, or Period, or New Stone Age, was a period in the development of human technology, beginning about 9500 BC in some parts of the Middle East, and later in other parts of the world. It is traditionally considered as the last part of the Stone Age...

 peoples as early as the 8th millennium BC. The wild olive tree originated in Asia Minor
Asia Minor
Asia Minor is a geographical location at the westernmost protrusion of Asia, also called Anatolia, and corresponds to the western two thirds of the Asian part of Turkey...

 in modern Turkey
Turkey
Turkey , known officially as the Republic of Turkey , is a Eurasian country located in Western Asia and in East Thrace in Southeastern Europe...

.

It is not clear when and where olive trees were first domesticated: in Asia Minor in the 6th millennium; along the Levant
Levant
The Levant or ) is the geographic region and culture zone of the "eastern Mediterranean littoral between Anatolia and Egypt" . The Levant includes most of modern Lebanon, Syria, Jordan, Israel, the Palestinian territories, and sometimes parts of Turkey and Iraq, and corresponds roughly to the...

ine coast stretching from the Sinai Peninsula
Sinai Peninsula
The Sinai Peninsula or Sinai is a triangular peninsula in Egypt about in area. It is situated between the Mediterranean Sea to the north, and the Red Sea to the south, and is the only part of Egyptian territory located in Asia as opposed to Africa, effectively serving as a land bridge between two...

 to modern Turkey in the 4th millennium; or somewhere in the Mesopotamian Fertile Crescent
Fertile Crescent
The Fertile Crescent, nicknamed "The Cradle of Civilization" for the fact the first civilizations started there, is a crescent-shaped region containing the comparatively moist and fertile land of otherwise arid and semi-arid Western Asia. The term was first used by University of Chicago...

 in the 3rd millennium.

A widespread view exists that the first cultivation took place on the island of Crete
Crete
Crete is the largest and most populous of the Greek islands, the fifth largest island in the Mediterranean Sea, and one of the thirteen administrative regions of Greece. It forms a significant part of the economy and cultural heritage of Greece while retaining its own local cultural traits...

. Archeological evidence suggest that olives were being grown in Crete as long ago as 2,500 B.C. The earliest surviving olive oil amphora
Amphora
An amphora is a type of vase-shaped, usually ceramic container with two handles and a long neck narrower than the body...

e date to 3500 BC (Early Minoan times), though the production of olive is assumed to have started before 4000 BC. An alternative view retains that olives were turned into oil by 4500 BC by Canaan
Canaan
Canaan is a historical region roughly corresponding to modern-day Israel, Palestine, Lebanon, and the western parts of Jordan...

ites in present-day Israel
Israel
The State of Israel is a parliamentary republic located in the Middle East, along the eastern shore of the Mediterranean Sea...

.
Homer
Homer
In the Western classical tradition Homer , is the author of the Iliad and the Odyssey, and is revered as the greatest ancient Greek epic poet. These epics lie at the beginning of the Western canon of literature, and have had an enormous influence on the history of literature.When he lived is...

 called it "liquid gold." In ancient Greece, athletes ritually rubbed it all over their bodies. Olive oil has been more than mere food to the peoples of the Mediterranean: it has been medicinal, magical, an endless source of fascination and wonder and the fountain of great wealth and power. Indeed the importance of the olive industry in ancient economies cannot be overstated. The tree is extremely hardy and its useful lifespan can be measured in centuries. Its wide and deep root system ensures its survival without additional watering, even in the water-sparse Mediterranean. It thrives close to the sea, where other plants cannot tolerate the increased salt content of underground water. Other than pruning in late spring, it needs minimal cultivation and its fruit matures in the late autumn in the Northern Mediterranean) or through the winter (further south), when other staple food harvests are over and there is no other agricultural work to be done. Olive collecting and processing is relatively straightforward, and needs minimal, mechanical technology. Olive oil, being almost pure fat, is dense in calories yet healthy, without adverse health effects. Unlike cereals which can be destroyed by humidity and pests in storage, olive oil can be very easily stored and will not go rancid for at least a year (unless needlessly exposed to light or extremely hot weather), by which time a fresh harvest will be available. The combination of these factors helped ensure that the olive industry has become the region's most dependable food and cash crop since prehistoric
Prehistory
Prehistory is the span of time before recorded history. Prehistory can refer to the period of human existence before the availability of those written records with which recorded history begins. More broadly, it refers to all the time preceding human existence and the invention of writing...

 times.

Besides food, olive oil has been used for religious ritual
Ritual
A ritual is a set of actions, performed mainly for their symbolic value. It may be prescribed by a religion or by the traditions of a community. The term usually excludes actions which are arbitrarily chosen by the performers....

s, medicine
Medicine
Medicine is the science and art of healing. It encompasses a variety of health care practices evolved to maintain and restore health by the prevention and treatment of illness....

s, as a fuel
Fuel
Fuel is any material that stores energy that can later be extracted to perform mechanical work in a controlled manner. Most fuels used by humans undergo combustion, a redox reaction in which a combustible substance releases energy after it ignites and reacts with the oxygen in the air...

 in oil lamp
Oil lamp
An oil lamp is an object used to produce light continuously for a period of time using an oil-based fuel source. The use of oil lamps began thousands of years ago and is continued to this day....

s, soap-making, and skin care application. The importance and antiquity of olive oil can be seen in the fact that the English word oil derives from c. 1175, olive oil, from Anglo-Fr. and O.N.Fr. olie, from O.Fr. oile (12c., Mod.Fr. huile), from L. oleum "oil, olive oil" (cf. It. olio), from Gk. elaion "olive tree", which may have been borrowed through trade networks from the Semitic Phoenician use of el'yon meaning "superior", probably in recognized comparison to other vegetable or animal fat
Fat
Fats consist of a wide group of compounds that are generally soluble in organic solvents and generally insoluble in water. Chemically, fats are triglycerides, triesters of glycerol and any of several fatty acids. Fats may be either solid or liquid at room temperature, depending on their structure...

s available at the time. Robin Lane Fox
Robin Lane Fox
Robin Lane Fox is an English historian, currently a Fellow of New College, Oxford and University of Oxford Reader in Ancient History.-Life:Lane Fox was educated at Eton and Magdalen College, Oxford....

 suggests that the Latin borrowing of Greek elaion for oil (Latin oleum) is itself a marker for improved Greek varieties of oil-producing olive, already present in Italy as Latin was forming, brought by Euboea
Euboea
Euboea is the second largest Greek island in area and population, after Crete. The narrow Euripus Strait separates it from Boeotia in mainland Greece. In general outline it is a long and narrow, seahorse-shaped island; it is about long, and varies in breadth from to...

n traders, whose presence in Latium is signaled by remains of their characteristic pottery, from the mid-eighth century.

Recent genetic studies suggest that species used by modern cultivators descend from multiple wild populations, but a detailed history of domestication is not yet understood.

Many ancient presses still exist in the Eastern Mediterranean region, and some dating to the Roman period are still in use today.

Eastern Mediterranean

Over 5,000 years ago oil was being extracted from olives in the Eastern Mediterranean. In the centuries that followed, olive presses became common, from the Atlantic shore of North Africa to Persia and from the Po Valley
Po Valley
The Po Valley, Po Plain, Plain of the Po, or Padan Plain is a major geographical feature of Italy. It extends approximately in an east-west direction, with an area of 46,000 km² including its Venetic extension not actually related to the Po River basin; it runs from the Western Alps to the...

 to the settlements along the Nile
Nile
The Nile is a major north-flowing river in North Africa, generally regarded as the longest river in the world. It is long. It runs through the ten countries of Sudan, South Sudan, Burundi, Rwanda, Democratic Republic of the Congo, Tanzania, Kenya, Ethiopia, Uganda and Egypt.The Nile has two major...

.

Olive trees and oil production in the Eastern Mediterranean can be traced to archives of the ancient city-state Ebla
Ebla
Ebla Idlib Governorate, Syria) was an ancient city about southwest of Aleppo. It was an important city-state in two periods, first in the late third millennium BC, then again between 1800 and 1650 BC....

 (2600–2240 BC), which were located on the outskirts of the Syria
Syria
Syria , officially the Syrian Arab Republic , is a country in Western Asia, bordering Lebanon and the Mediterranean Sea to the West, Turkey to the north, Iraq to the east, Jordan to the south, and Israel to the southwest....

n city Aleppo
Aleppo
Aleppo is the largest city in Syria and the capital of Aleppo Governorate, the most populous Syrian governorate. With an official population of 2,301,570 , expanding to over 2.5 million in the metropolitan area, it is also one of the largest cities in the Levant...

. Here some dozen documents dated 2400 BC describe lands of the king and the queen. These belonged to a library of clay tablets perfectly preserved by having been baked in the fire that destroyed the palace. A later source is the frequent mentions of oil in Tanakh
Tanakh
The Tanakh is a name used in Judaism for the canon of the Hebrew Bible. The Tanakh is also known as the Masoretic Text or the Miqra. The name is an acronym formed from the initial Hebrew letters of the Masoretic Text's three traditional subdivisions: The Torah , Nevi'im and Ketuvim —hence...

.

Dynastic Egyptians
Ancient Egypt
Ancient Egypt was an ancient civilization of Northeastern Africa, concentrated along the lower reaches of the Nile River in what is now the modern country of Egypt. Egyptian civilization coalesced around 3150 BC with the political unification of Upper and Lower Egypt under the first pharaoh...

 before 2000 BC imported olive oil from Crete, Syria and Canaan
Canaan
Canaan is a historical region roughly corresponding to modern-day Israel, Palestine, Lebanon, and the western parts of Jordan...

 and oil was an important item of commerce and wealth. Remains of olive oil have been found in jugs over 4,000 years old in a tomb on the island of Naxos in the Aegean Sea
Aegean Sea
The Aegean Sea[p] is an elongated embayment of the Mediterranean Sea located between the southern Balkan and Anatolian peninsulas, i.e., between the mainlands of Greece and Turkey. In the north, it is connected to the Marmara Sea and Black Sea by the Dardanelles and Bosporus...

. Sinuhe, the Egyptian exile who lived in northern Canaan about 1960 BC, wrote of abundant olive trees.

Until 1500 BC, eastern coastal areas of the Mediterranean were most heavily cultivated. Olive trees were certainly cultivated by the Late Minoan period (1500 BC) in Crete, and perhaps as early as the Early Minoan. The cultivation of olive trees in Crete became particularly intense in the post-palatial period and played an important role in the island's economy. The Minoans used olive oil in religious ceremonies. The oil became a principal product of the Minoan civilization
Minoan civilization
The Minoan civilization was a Bronze Age civilization that arose on the island of Crete and flourished from approximately the 27th century BC to the 15th century BC. It was rediscovered at the beginning of the 20th century through the work of the British archaeologist Arthur Evans...

, where it is thought to have represented wealth. The Minoans put the pulp into settling tanks and, when the oil had risen to the top, drained the water from the bottom. Olive tree growing reached Iberia
Iberian Peninsula
The Iberian Peninsula , sometimes called Iberia, is located in the extreme southwest of Europe and includes the modern-day sovereign states of Spain, Portugal and Andorra, as well as the British Overseas Territory of Gibraltar...

 and Etruscan
Etruscan civilization
Etruscan civilization is the modern English name given to a civilization of ancient Italy in the area corresponding roughly to Tuscany. The ancient Romans called its creators the Tusci or Etrusci...

 cities well before the 8th century BC through trade with the Phoenicia
Phoenicia
Phoenicia , was an ancient civilization in Canaan which covered most of the western, coastal part of the Fertile Crescent. Several major Phoenician cities were built on the coastline of the Mediterranean. It was an enterprising maritime trading culture that spread across the Mediterranean from 1550...

ns and Carthage
Carthage
Carthage , implying it was a 'new Tyre') is a major urban centre that has existed for nearly 3,000 years on the Gulf of Tunis, developing from a Phoenician colony of the 1st millennium BC...

, then spread into Southern Gaul
Gaul
Gaul was a region of Western Europe during the Iron Age and Roman era, encompassing present day France, Luxembourg and Belgium, most of Switzerland, the western part of Northern Italy, as well as the parts of the Netherlands and Germany on the left bank of the Rhine. The Gauls were the speakers of...

 by the Celt
Celt
The Celts were a diverse group of tribal societies in Iron Age and Roman-era Europe who spoke Celtic languages.The earliest archaeological culture commonly accepted as Celtic, or rather Proto-Celtic, was the central European Hallstatt culture , named for the rich grave finds in Hallstatt, Austria....

ic tribes during the 7th century BC.

The first recorded oil extraction is known from the Hebrew Bible and took place during the Exodus
The Exodus
The Exodus is the story of the departure of the Israelites from ancient Egypt described in the Hebrew Bible.Narrowly defined, the term refers only to the departure from Egypt described in the Book of Exodus; more widely, it takes in the subsequent law-givings and wanderings in the wilderness...

 from Egypt, during the 13th century BC. During this time, the oil was derived through hand-squeezing the berries and stored in special containers under guard of the priests. A commercial mill for non-sacramental use of oil was in use in the tribal Confederation and later in 1000 BC, the fertile crescent
Fertile Crescent
The Fertile Crescent, nicknamed "The Cradle of Civilization" for the fact the first civilizations started there, is a crescent-shaped region containing the comparatively moist and fertile land of otherwise arid and semi-arid Western Asia. The term was first used by University of Chicago...

, and area consisting of present day Palestine, Lebanon, and Israel. Over 100 olive presses have been found in Tel Miqne (Ekron), where the Biblical Philistines
Philistines
Philistines , Pleshet or Peleset, were a people who occupied the southern coast of Canaan at the beginning of the Iron Age . According to the Bible, they ruled the five city-states of Gaza, Askelon, Ashdod, Ekron and Gath, from the Wadi Gaza in the south to the Yarqon River in the north, but with...

 also produced oil. These presses are estimated to have had output of between 1,000 and 3,000 tons of olive oil per season.

Olive trees were planted in the entire Mediterranean basin during evolution of the Roman republic
Roman Republic
The Roman Republic was the period of the ancient Roman civilization where the government operated as a republic. It began with the overthrow of the Roman monarchy, traditionally dated around 508 BC, and its replacement by a government headed by two consuls, elected annually by the citizens and...

 and empire
Roman Empire
The Roman Empire was the post-Republican period of the ancient Roman civilization, characterised by an autocratic form of government and large territorial holdings in Europe and around the Mediterranean....

. According to the historian Pliny
Pliny the Elder
Gaius Plinius Secundus , better known as Pliny the Elder, was a Roman author, naturalist, and natural philosopher, as well as naval and army commander of the early Roman Empire, and personal friend of the emperor Vespasian...

, Italy had "excellent olive oil at reasonable prices" by the first century AD, "the best in the Mediterranean", he maintained, a claim probably disputed by many ancient olive growers. Thus olive oil was very common in Hellene and Latin
Latin
Latin is an Italic language originally spoken in Latium and Ancient Rome. It, along with most European languages, is a descendant of the ancient Proto-Indo-European language. Although it is considered a dead language, a number of scholars and members of the Christian clergy speak it fluently, and...

 cuisine. According to Herodotus
Herodotus
Herodotus was an ancient Greek historian who was born in Halicarnassus, Caria and lived in the 5th century BC . He has been called the "Father of History", and was the first historian known to collect his materials systematically, test their accuracy to a certain extent and arrange them in a...

, Apollodorus
Bibliotheca (Pseudo-Apollodorus)
The Bibliotheca , in three books, provides a comprehensive summary of traditional Greek mythology and heroic legends, "the most valuable mythographical work that has come down from ancient times," Aubrey Diller observed, whose "stultifying purpose" was neatly expressed in the epigram noted by...

, Plutarch
Plutarch
Plutarch then named, on his becoming a Roman citizen, Lucius Mestrius Plutarchus , c. 46 – 120 AD, was a Greek historian, biographer, essayist, and Middle Platonist known primarily for his Parallel Lives and Moralia...

, Pausanias, Ovid
Ovid
Publius Ovidius Naso , known as Ovid in the English-speaking world, was a Roman poet who is best known as the author of the three major collections of erotic poetry: Heroides, Amores, and Ars Amatoria...

 and more, the city of Athens
Athens
Athens , is the capital and largest city of Greece. Athens dominates the Attica region and is one of the world's oldest cities, as its recorded history spans around 3,400 years. Classical Athens was a powerful city-state...

 obtained its name because Athenians considered olive oil essential, preferring the offering of the goddess Athena
Athena
In Greek mythology, Athena, Athenê, or Athene , also referred to as Pallas Athena/Athene , is the goddess of wisdom, courage, inspiration, civilization, warfare, strength, strategy, the arts, crafts, justice, and skill. Minerva, Athena's Roman incarnation, embodies similar attributes. Athena is...

 (an olive tree) over the offering of Poseidon
Poseidon
Poseidon was the god of the sea, and, as "Earth-Shaker," of the earthquakes in Greek mythology. The name of the sea-god Nethuns in Etruscan was adopted in Latin for Neptune in Roman mythology: both were sea gods analogous to Poseidon...

 (a spring of salt
Salt
In chemistry, salts are ionic compounds that result from the neutralization reaction of an acid and a base. They are composed of cations and anions so that the product is electrically neutral...

 water gushing out of a cliff).

The Sparta
Sparta
Sparta or Lacedaemon, was a prominent city-state in ancient Greece, situated on the banks of the River Eurotas in Laconia, in south-eastern Peloponnese. It emerged as a political entity around the 10th century BC, when the invading Dorians subjugated the local, non-Dorian population. From c...

ns were the Hellenes who used oil to rub themselves while exercising in the gymnasia
Gymnasium (ancient Greece)
The gymnasium in ancient Greece functioned as a training facility for competitors in public games. It was also a place for socializing and engaging in intellectual pursuits. The name comes from the Ancient Greek term gymnós meaning "naked". Athletes competed in the nude, a practice said to...

. The practice served to eroticise and highlight the beauty of the male body. From its beginnings early in the seventh century BC, the decorative use of olive oil quickly spread to all of Hellenic city states, together with naked appearance of athletes, and lasted close to a thousand years despite its great expense.

Varieties

Among the many different olive varieties or cultivars there are: in Greece
Greece
Greece , officially the Hellenic Republic , and historically Hellas or the Republic of Greece in English, is a country in southeastern Europe....

 Koroneiki, Lianolia, Chondrolia (aka Throumbolia), Tsounati, Patrinia olive
Patrinia olive
Patrinia olive is a Greek variety of olive tree grown primarily in Aigialeia, Greece. The olive fruit is used exclusively for oil production and it has a high oil concentration of around 25%...

 and more.

In Spain, the most important varieties are the Picual, Arbequina, Hojiblanca, and Manzanilla de Jaén; in France, Picholine
Picholine
The Picholine is a French cultivar of olives. It is the most widely available cultivar in France. Though originally from Gard in southern France, it is today grown all over the world. The Picholine is best known as a cocktail olive, though it is also used to make olive oil.-Extent:The Picholine...

; in California, Mission; in Portugal, Galega; in Croatia
Croatia
Croatia , officially the Republic of Croatia , is a unitary democratic parliamentary republic in Europe at the crossroads of the Mitteleuropa, the Balkans, and the Mediterranean. Its capital and largest city is Zagreb. The country is divided into 20 counties and the city of Zagreb. Croatia covers ...

, Oblica and Leccino. The oil from the varieties varies in flavour and stability (shelf life).

In Italy, Frantoio, Leccino Pendolino, and Moraiolo are the most famous varieties of cultivars.

Production and consumption

Three countries are the major olive oil producers in the world. First is Spain, second is Italy and third is Greece. Together, they produce more than 75% of the world production. In Italy the major producers are called "Città dell'Olio", "oil cities"; two of most important are Olevano Sul Tusciano
Olevano sul Tusciano
Olevano sul Tusciano is a town and comune in the province of Salerno in the Campania region of south-western Italy.- Civil Architectures :*Villa romana di S. Maria a Corte.*Castrum Olibani - Longobard castle.* Pope gardens in Salitto...

, in Campania
Campania
Campania is a region in southern Italy. The region has a population of around 5.8 million people, making it the second-most-populous region of Italy; its total area of 13,590 km² makes it the most densely populated region in the country...

 or Siena
Siena
Siena is a city in Tuscany, Italy. It is the capital of the province of Siena.The historic centre of Siena has been declared by UNESCO a World Heritage Site. It is one of the nation's most visited tourist attractions, with over 163,000 international arrivals in 2008...

, in Tuscany
Tuscany
Tuscany is a region in Italy. It has an area of about 23,000 square kilometres and a population of about 3.75 million inhabitants. The regional capital is Florence ....

.

Australia now produces a substantial amount of olive oil. Many Australian producers only make premium oils, while a number of corporate growers operate groves of a million trees or more and produce oils for the general market. Australian olive oil is exported to Asia, Europe and the United States.

In North America, Italian and Spanish olive oils are the best-known, and top-quality extra-virgin oils from Spain, Italy, and Greece are sold at high prices, often in "prestige" packaging. A large part of U.S. olive oil imports come from Spain, Italy, and Turkey. The U.S. imported 47800000 gallons (180,942.7 m³) of olive oil in 1998, of which 34600000 gallons (130,975.3 m³) came from Italy.

The Republic of South Africa, Argentina and Chile also produce extra virgin olive oil.

Olive orchards in Arizona, California, and Texas are producing olive oil that is appearing on USA grocery market shelves along side the Mediterranean olive oils.

Regulation

The International Olive Council (IOC) is an intergovernmental organization based in Madrid
Madrid
Madrid is the capital and largest city of Spain. The population of the city is roughly 3.3 million and the entire population of the Madrid metropolitan area is calculated to be 6.271 million. It is the third largest city in the European Union, after London and Berlin, and its metropolitan...

, Spain
Spain
Spain , officially the Kingdom of Spain languages]] under the European Charter for Regional or Minority Languages. In each of these, Spain's official name is as follows:;;;;;;), is a country and member state of the European Union located in southwestern Europe on the Iberian Peninsula...

, with 23 member states. It promotes olive oil around the world by tracking production, defining quality standards, and monitoring authenticity. More than 85% of the world's olives are grown in IOC member nations. The United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...

 is not a member of the IOC, and the U.S. Department of Agriculture
United States Department of Agriculture
The United States Department of Agriculture is the United States federal executive department responsible for developing and executing U.S. federal government policy on farming, agriculture, and food...

 does not legally recognize its classifications (such as extra-virgin olive oil). The USDA uses a different system, which it defined in 1948 before the IOC existed. On October 25, 2010, the United States adopted new olive oil standards, a revision of those that had been in place since 1948, which affect importers and domestic growers and producers by ensuring conformity with the benchmarks commonly accepted in the U.S. and abroad.

Olive oil is classified by how it was produced, by its chemistry
Chemistry
Chemistry is the science of matter, especially its chemical reactions, but also its composition, structure and properties. Chemistry is concerned with atoms and their interactions with other atoms, and particularly with the properties of chemical bonds....

, and by panels that perform olive oil taste testing. The IOC officially governs 95% of international production and holds great influence over the rest. The EU regulates the use of different protected designation of origin
Protected designation of origin
Protected Geographical Status is a legal framework defined in European Union law to protect the names of regional foods. Protected Designation of Origin , Protected Geographical Indication and Traditional Speciality Guaranteed are distinct regimes of geographical indications within the framework...

 labels for olive oils.

U.S. Customs regulations on "country of origin" state that if a non-origin nation is shown on the label, then the real origin must be shown on the same side of the label and in comparable size letters so as not to mislead the consumer. Yet most major U.S. brands continue to put "imported from Italy" on the front label in large letters and other origins on the back in very small print. "In fact, olive oil labeled 'Italian' often comes from Turkey, Tunisia, Morocco, Spain, and Greece." These products are a mixture of olive oil from more than one nation and it is not clear what percentage of the olive oil is really of Italian origin. This practice makes it difficult for high quality, lower cost producers outside of Italy to enter the U.S. market, and for genuine Italian producers to compete.

Adulteration

The adulteration of oil can be no more serious than passing off inferior, but safe, product as superior olive oil, but there are no guarantees. It is believed that almost 700 people died as a consequence of consuming rapeseed oil adulterated with aniline
Aniline
Aniline, phenylamine or aminobenzene is an organic compound with the formula C6H5NH2. Consisting of a phenyl group attached to an amino group, aniline is the prototypical aromatic amine. Being a precursor to many industrial chemicals, its main use is in the manufacture of precursors to polyurethane...

 intended for use as an industrial lubricant, but sold in 1981 as olive oil in Spain (see toxic oil syndrome
Toxic oil syndrome
Toxic Oil Syndrome or simply Toxic Syndrome was the name given to a disease outbreak in Spain in 1981, which killed over 600 people. Its first appearance was as a lung disease, with unusual features: though the symptoms initially resembled a lung infection, antibiotics were ineffective...

).

An article by Tom Mueller in the August 13, 2007, issue of The New Yorker
The New Yorker
The New Yorker is an American magazine of reportage, commentary, criticism, essays, fiction, satire, cartoons and poetry published by Condé Nast...

alleges that regulation, particularly in Italy, is extremely lax and corrupt. Mueller states that major Italian shippers routinely adulterate olive oil and that only about 40% of olive oil sold as "extra virgin" actually meets the specification. In some cases, colza oil
Colza oil
Colza oil is a nondrying oil obtained from the seeds of Brassica rapa, var. oleifera, a variety of the plant that produces turnips. Colza is extensively cultivated in France, Belgium, the United States, the Netherlands and Germany and Poland. In France, especially, the extraction of the oil is an...

 (Swedish turnip) with added color and flavor has been labeled and sold as olive oil. This extensive fraud prompted the Italian government to mandate a new labeling law in 2007 for companies selling olive oil, under which every bottle of Italian olive oil would have to declare the farm and press on which it was produced, as well as display a precise breakdown of the oils used, for blended oils. In February 2008, however, EU officials took issue with the new law, stating that under EU rules such labeling should be voluntary rather than compulsory. Under EU rules, olive oil may be sold as Italian even if it only contains a small amount of Italian oil.

In March 2008, 400 Italian police officers conducted "Operation Golden Oil", arresting 23 people and confiscating 85 farms after an investigation revealed a large-scale scheme to relabel oils from other Mediterranean nations as Italian. In April 2008, another operation impounded seven olive oil plants and arrested 40 people in nine provinces of northern and southern Italy for adding chlorophyll
Chlorophyll
Chlorophyll is a green pigment found in almost all plants, algae, and cyanobacteria. Its name is derived from the Greek words χλωρος, chloros and φύλλον, phyllon . Chlorophyll is an extremely important biomolecule, critical in photosynthesis, which allows plants to obtain energy from light...

 to sunflower
Sunflower oil
Sunflower oil is the non-volatile oil expressed from sunflower seeds. Sunflower oil is commonly used in food as a frying oil, and in cosmetic formulations as an emollient. Sunflower oil was first industrially produced in 1835 in the Russian Empire.- Composition :Sunflower oil is mainly a...

 and soybean oil
Soybean oil
Soybean oil is a vegetable oil extracted from the seeds of the soybean . It is one of the most widely consumed cooking oils. As a drying oil, processed soybean oil is also used as a base for printing inks and oil paints...

, and selling it as extra virgin olive oil, both in Italy and abroad; 25,000 liters of the fake oil were seized and prevented from being exported.

On March 15, 2011, the Florence, Italy prosecutor's office, working in conjunction with the forestry department, indicted two managers and an officer of Carapelli, one of the brands of the Spanish company Grupo SOS (which recently changed its name to Deoleo). The charges involved falsified documents and food fraud. Carapelli lawyer Neri Pinucci said the company was not worried about the charges and that "the case is based on an irregularity in the documents."

Commercial grades

All production begins by transforming the olive fruit into olive paste. This paste is then malaxed
Malaxation
Malaxation, a stage in olive oil extraction, is the action of slowly churning or mixing milled olives, typically for 20 to 40 minutes. The churning allows the smaller droplets of oil released by the milling process to aggregate and be more easily separated. The paste is normally heated to around...

 (slowly churned or mixed) to allow the microscopic oil droplets to concentrate. The oil is extracted by means of pressure (traditional method) or centrifugation
Centrifuge
A centrifuge is a piece of equipment, generally driven by an electric motor , that puts an object in rotation around a fixed axis, applying a force perpendicular to the axis...

 (modern method). After extraction the remnant solid substance, called pomace
Olive mill pomace
Olive mill pomace is a by product from the olive oil mill extraction process. Usually it is used as fuel in a cogeneration system or as organic fertiliser after a composting operation....

, still contains a small quantity of oil.

The grades of oil extracted from the olive fruit can be classified as:
  • Virgin means the oil was produced by the use of physical means and no chemical treatment. The term virgin oil referring to production is different from Virgin Oil on a retail label (see next section).
  • Refined means that the oil has been chemically treated to neutralize strong tastes (characterized as defects) and neutralize the acid content (free fatty acids). Refined oil is commonly regarded as lower quality than virgin oil; oils with the retail labels extra-virgin olive oil and virgin olive oil cannot contain any refined oil.
  • Olive pomace oil
    Olive Pomace Oil
    Olive Pomace Oil is the oil that is extracted from the olive pulp after the first press. Once the mechanical oil extraction of olive oil is complete approximately 5-8% of the oil remains in the pulp, which then needs to be extracted with the help of solvents, an industrial technique used in the...

    means oil extracted from the pomace using solvents, mostly hexane
    Hexane
    Hexane is a hydrocarbon with the chemical formula C6H14; that is, an alkane with six carbon atoms.The term may refer to any of four other structural isomers with that formula, or to a mixture of them. In the IUPAC nomenclature, however, hexane is the unbranched isomer ; the other four structures...

    , and by heat.


Quantitative analysis
Quantitative analysis (chemistry)
In chemistry, quantitative analysis is the determination of the absolute or relative abundance of one, several or all particular substance present in a sample....

 can determine the oil's acidity, defined as the percent, measured by weight, of free oleic acid
Oleic acid
Oleic acid is a monounsaturated omega-9 fatty acid found in various animal and vegetable fats. It has the formula CH37CH=CH7COOH. It is an odorless, colourless oil, although commercial samples may be yellowish. The trans isomer of oleic acid is called elaidic acid...

 it contains. This is a measure of the oil's chemical degradation; as the oil degrades, more fatty acids are freed from the glyceride
Glyceride
Glycerides, more correctly known as acylglycerols, are esters formed from glycerol and fatty acids.Glycerol has three hydroxyl functional groups, which can be esterified with one, two, or three fatty acids to form monoglycerides, diglycerides, and triglycerides.Vegetable oils and animal fats...

s, increasing the level of free acidity and thereby increasing rancidity
Rancidification
Rancidification is the chemical decomposition of fats, oils and other lipids . When these processes occur in food, undesirable odors and flavors can result. In some cases, however, the flavors can be desirable . In processed meats, these flavors are collectively known as "warmed over flavor"...

. Another measure of the oil's chemical degradation is the organic peroxide
Organic peroxide
Organic peroxides are organic compounds containing the peroxide functional group . If the R' is hydrogen, the compound is called an organic hydroperoxide. Peresters have general structure RCOOR. The O-O bond easily breaks and forms free radicals of the form RO·...

 level, which measures the degree to which the oil is oxidized, another cause of rancidity.

To classify it by taste, olive oil is subjectively judged by a panel of professional tasters in a blind taste test
Blind taste test
In marketing, a blind taste test is often used as a tool for companies to compare their brand to another brand. For example, the Pepsi Challenge is a famous taste test that has been run by Pepsi since 1975 as a method to show their superiority to Coca-Cola. Taste tests are also a tool sometimes...

. This is also called its organoleptic quality.

Retail grades in IOC member nations

In countries that adhere to the standards of the IOC the labels in stores show an oil's grade.
  • 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; the percentage is far higher in the Mediterranean countries (Greece: 80%, Italy: 45%, Spain 30%). It is used on salads, added at the table to soups and stews and for dipping.
  • Virgin olive oil comes from virgin oil production only, has an acidity less than 2%, and is judged to have a good taste.
  • Pure olive oil. Oils labeled as Pure olive oil or Olive oil are usually a blend of refined and virgin production oil.
  • Olive oil is a blend of virgin and refined production oil, of no more than 1.5% acidity. It commonly lacks a strong flavor.
  • Olive pomace oil
    Olive Pomace Oil
    Olive Pomace Oil is the oil that is extracted from the olive pulp after the first press. Once the mechanical oil extraction of olive oil is complete approximately 5-8% of the oil remains in the pulp, which then needs to be extracted with the help of solvents, an industrial technique used in the...

    is refined pomace olive oil often blended with some virgin oil. It is fit for consumption, but may not be described simply as olive oil. It has a more neutral flavor than pure or virgin olive oil, making it unfashionable among connoisseurs; however, it has the same fat composition as regular olive oil, rendering it the same health benefits. It also has a high smoke point, and thus is widely used in restaurants as well as home cooking in some countries.
  • Lampante oil is olive oil not suitable as food; lampante comes from olive oil's long-standing use in oil-burning lamps. Lampante oil is mostly used in the industrial market.
  • Refined olive oil is the olive oil obtained from virgin olive oils by refining methods that 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 with a high acidity level and/or organoleptic defects that are eliminated after refining. 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.

Retail grades in the United States from the USDA

As of October 25, 2010, the U.S. Standards for Grades of Olive Oil and Olive-Pomace Oil went into effect.

As the United States is not a member, the IOC retail grades have no legal meaning in that country; terms such as "extra virgin" may be used without legal restrictions.

The U.S. Department of Agriculture (USDA) currently has a four-part grading of olive oil based on acidity, absence of defects, odor and flavor:
  • U.S. Extra Virgin Olive Oil for oil with excellent flavor and odor and free fatty acid content of 0.8g per 100g (0.8%);
  • U.S. Virgin Olive Oil for oil with reasonably good flavor and odor and free fatty acid content of not more than 2g per 100g (2%);
  • U.S. Virgin Olive Oil Not Fit For Human Consumption Without Further Processing is a virgin oil of poor flavor and odor;
  • U.S. Olive Oil is an oil mix of both virgin and refined oils;
  • U.S. Refined Olive Oil is an oil made from refined oils with some restrictions on the processing;


These grades are voluntary. Certification is available from the USDA on a fee-for-service basis.

Previous USDA ratings

The U.S. Department of Agriculture (USDA) previously listed four grades of olive oil. These grades were established in 1948, and are 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".


These grades are entirely voluntary and are available from the USDA on a fee-for-service basis.

Label wording

  • The different names for olive oil indicate the degree of processing the oil has undergone as well as the quality of the oil. Extra-virgin olive oil is the highest grade available, followed by virgin olive oil. The word "virgin" indicates that the olives have been pressed to extract the oil; no heat or chemicals have been used during the extraction process, and the oil is pure and unrefined. Virgin olive oils are the healthiest, since they contain the highest levels of polyphenols, antioxidants that have been linked with better health.
  • "Made from refined olive oils" means that the taste and acidity were chemically controlled.
  • Cold pressed or Cold extraction means "that the oil was not heated over a certain temperature (usually 80 °F (26.7 °C)) during processing, thus retaining more nutrients and undergoing less degradation."
  • First cold pressed means "that the fruit of the olive was crushed exactly one time-i.e., the first press. The cold refers to the temperature range of the fruit at the time it is crushed." In Calabria (Italy) the olives are collected in October. In regions like Tuscany or Liguria, the olives collected in November and ground often at night are too cold to be processed efficiently without heating. The paste is regularly heated above the environmental temperatures, which may be as low as 10-15 °C, to extract the oil efficiently with only physical means. Olives pressed in warm regions like Southern Italy or Northern Africa may be pressed at significantly higher temperatures although not heated. While it is important that the pressing temperatures be as low as possible (generally below 25 °C) there is no international reliable definition of "cold pressed".
    Furthermore, there is no "second" press of virgin oil, so the term "first press" means only that the oil was produced in a press vs. other possible methods.
  • PDO
    Protected designation of origin
    Protected Geographical Status is a legal framework defined in European Union law to protect the names of regional foods. Protected Designation of Origin , Protected Geographical Indication and Traditional Speciality Guaranteed are distinct regimes of geographical indications within the framework...

    and PGI
    Protected designation of origin
    Protected Geographical Status is a legal framework defined in European Union law to protect the names of regional foods. Protected Designation of Origin , Protected Geographical Indication and Traditional Speciality Guaranteed are distinct regimes of geographical indications within the framework...

    refers to olive oils with "exceptional properties and quality derived from their place of origin as well as from the way of their production".
  • The label may indicate that the oil was bottled or packed in a stated country. This does not necessarily mean that the oil was produced there. The origin of the oil may sometimes be marked elsewhere on the label; it may be a mixture of oils from more than one country.
  • The U.S. Food and Drug Administration permitted a claim on olive oil labels stating: "Limited and not conclusive scientific evidence suggests that eating about two tablespoons (23g) of olive oil daily may reduce the risk of coronary heart disease."

Unique extra virgin olive oils

  • List of Greek Protected designation of origin
    Protected designation of origin
    Protected Geographical Status is a legal framework defined in European Union law to protect the names of regional foods. Protected Designation of Origin , Protected Geographical Indication and Traditional Speciality Guaranteed are distinct regimes of geographical indications within the framework...

     PDO and Protected Geographical Indication (PGI)
    Extra Virgin Olive oils:

Certification Name
P.G.I. Agios Mattheos Corfu
P.D.O. Apokoronas Chania Crete
P.D.O. Arxanes Irakliou Crete
P.D.O. Viannos Irakliou Crete
P.D.O. Vorios Mylopotamos Rethymnis Crete
P.D.O. Trizinia
P.D.O. Thrapsano
P.G.I. Zakynthos
P.G.I. Thassos
P.G.I. Kefalonia
P.D.O. Kolymvari Chania Crete
P.D.O. Kranidi Argolidas
P.D.O. Krokees Lakonias
P.G.I. Olympia
P.G.I. Chania Crete
P.G.I. Lakonia
P.G.I. Lesvos or Mytilini
P.D.O. Lygourio Asklipiiou
P.D.O. Peza Irakliou Crete
P.D.O. Petrina Lakonias
P.G.I. Preveza
P.D.O. Finiki Lakonias
P.G.I. Rodos
P.G.I. Samos
P.D.O. Kalamata
P.D.O. Sitia Lasithiou Crete
P.D.O. Selino Crete

Global consumption

Greece has by far the largest per capita consumption of olive oil worldwide, over 26 liters per person per year; Spain
Spain
Spain , officially the Kingdom of Spain languages]] under the European Charter for Regional or Minority Languages. In each of these, Spain's official name is as follows:;;;;;;), is a country and member state of the European Union located in southwestern Europe on the Iberian Peninsula...

 and Italy
Italy
Italy , officially the Italian Republic languages]] under the European Charter for Regional or Minority Languages. In each of these, Italy's official name is as follows:;;;;;;;;), is a unitary parliamentary republic in South-Central Europe. To the north it borders France, Switzerland, Austria and...

, around 14 l; Tunisia
Tunisia
Tunisia , officially the Tunisian RepublicThe long name of Tunisia in other languages used in the country is: , is the northernmost country in Africa. It is a Maghreb country and is bordered by Algeria to the west, Libya to the southeast, and the Mediterranean Sea to the north and east. Its area...

, Portugal
Portugal
Portugal , officially the Portuguese Republic is a country situated in southwestern Europe on the Iberian Peninsula. Portugal is the westernmost country of Europe, and is bordered by the Atlantic Ocean to the West and South and by Spain to the North and East. The Atlantic archipelagos of the...

, Syria
Syria
Syria , officially the Syrian Arab Republic , is a country in Western Asia, bordering Lebanon and the Mediterranean Sea to the West, Turkey to the north, Iraq to the east, Jordan to the south, and Israel to the southwest....

, Jordan
Jordan
Jordan , officially the Hashemite Kingdom of Jordan , Al-Mamlaka al-Urduniyya al-Hashemiyya) is a kingdom on the East Bank of the River Jordan. The country borders Saudi Arabia to the east and south-east, Iraq to the north-east, Syria to the north and the West Bank and Israel to the west, sharing...

 and Lebanon
Lebanon
Lebanon , officially the Republic of LebanonRepublic of Lebanon is the most common term used by Lebanese government agencies. The term Lebanese Republic, a literal translation of the official Arabic and French names that is not used in today's world. Arabic is the most common language spoken among...

, around 8 l. Northern Europe
Northern Europe
Northern Europe is the northern part or region of Europe. Northern Europe typically refers to the seven countries in the northern part of the European subcontinent which includes Denmark, Estonia, Latvia, Lithuania, Norway, Finland and Sweden...

 and North America consume far less, around 0.7 l, but the consumption of olive oil outside its home territory has been rising steadily.

Global market

The main producing and consuming countries are:
Country Production in tons (2009) Production % (2009) Consumption (2005) Annual per capita consumption (kg)
World
World
World is a common name for the whole of human civilization, specifically human experience, history, or the human condition in general, worldwide, i.e. anywhere on Earth....

2,907,985 100% 100% 0.43
Spain
Spain
Spain , officially the Kingdom of Spain languages]] under the European Charter for Regional or Minority Languages. In each of these, Spain's official name is as follows:;;;;;;), is a country and member state of the European Union located in southwestern Europe on the Iberian Peninsula...

1,199,200 41.2% 20% 13.62
Italy
Italy
Italy , officially the Italian Republic languages]] under the European Charter for Regional or Minority Languages. In each of these, Italy's official name is as follows:;;;;;;;;), is a unitary parliamentary republic in South-Central Europe. To the north it borders France, Switzerland, Austria and...

587,700 20.2% 30% 12.35
Greece
Greece
Greece , officially the Hellenic Republic , and historically Hellas or the Republic of Greece in English, is a country in southeastern Europe....

332,600 11.4% 9% 23.7
Syria
Syria
Syria , officially the Syrian Arab Republic , is a country in Western Asia, bordering Lebanon and the Mediterranean Sea to the West, Turkey to the north, Iraq to the east, Jordan to the south, and Israel to the southwest....

168,163 5.8% 3% 7
Tunisia
Tunisia
Tunisia , officially the Tunisian RepublicThe long name of Tunisia in other languages used in the country is: , is the northernmost country in Africa. It is a Maghreb country and is bordered by Algeria to the west, Libya to the southeast, and the Mediterranean Sea to the north and east. Its area...

150,000 5.2% 2% 11.1
Turkey
Turkey
Turkey , known officially as the Republic of Turkey , is a Eurasian country located in Western Asia and in East Thrace in Southeastern Europe...

143,600 4.9% 2% 1.2
Morocco
Morocco
Morocco , officially the Kingdom of Morocco , is a country located in North Africa. It has a population of more than 32 million and an area of 710,850 km², and also primarily administers the disputed region of the Western Sahara...

95,300 3.3% 2% 1.8
Portugal
Portugal
Portugal , officially the Portuguese Republic is a country situated in southwestern Europe on the Iberian Peninsula. Portugal is the westernmost country of Europe, and is bordered by the Atlantic Ocean to the West and South and by Spain to the North and East. The Atlantic archipelagos of the...

53,300 1.8% 2% 7.1
France
France
The French Republic , The French Republic , The French Republic , (commonly known as France , is a unitary semi-presidential republic in Western Europe with several overseas territories and islands located on other continents and in the Indian, Pacific, and Atlantic oceans. Metropolitan France...

6,300 0.2% 4% 1.34
United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...

2,700 0.1% 8% 0.56
Others 169,122 5.8% 18% 1.18

  • In 2011 Jordan
    Jordan
    Jordan , officially the Hashemite Kingdom of Jordan , Al-Mamlaka al-Urduniyya al-Hashemiyya) is a kingdom on the East Bank of the River Jordan. The country borders Saudi Arabia to the east and south-east, Iraq to the north-east, Syria to the north and the West Bank and Israel to the west, sharing...

     production of olive was 175,000 tons 143,000 tons transformed into olive oil. And the annual per capita consumption in Jordan
    Jordan
    Jordan , officially the Hashemite Kingdom of Jordan , Al-Mamlaka al-Urduniyya al-Hashemiyya) is a kingdom on the East Bank of the River Jordan. The country borders Saudi Arabia to the east and south-east, Iraq to the north-east, Syria to the north and the West Bank and Israel to the west, sharing...

     was 5 kg.

Extraction

Olive oil is produced by grinding olives and extracting the oil by mechanical or chemical means. Green olives usually produce more bitter oil, and overripe olives can produce oil that is rancid, so for good extra virgin olive oil care is taken to make sure the olives are perfectly ripened. The process is generally as follows:
  1. The olives are ground into paste using large millstones (traditional method) or steel drums (modern method).
  2. If ground with mill stones, the olive paste generally stays under the stones for 30 to 40 minutes. A shorter grinding process may result in a more raw paste that produces less oil and has a less ripe taste, a longer process may increase oxidation of the paste and reduce the flavor. After grinding, the olive paste is spread on fiber disks, which are stacked on top of each other in a column, then placed into the press. Pressure is then applied onto the column to separate the vegetal liquid from the paste. This liquid still contains a significant amount of water. Traditionally the oil was shed from the water by gravity (oil is less dense than water). This very slow separation process has been replaced by centrifugation, which is much faster and more thorough. The centrifuges have one exit for the (heavier) watery part and one for the oil. Olive oil should not contain significant traces of vegetal water as this accelerates the process of organic degeneration by microorganisms. The separation in smaller oil mills is not always perfect, thus sometimes a small watery deposit containing organic particles can be found at the bottom of oil bottles.
  3. In modern steel drum mills the grinding process takes about 20 minutes. After grinding, the paste is stirred slowly for another 20 to 30 minutes in a particular container (malaxation), where the microscopic oil drops unite into bigger drops, which facilitates the mechanical extraction. The paste is then pressed by centrifugation/ the water is thereafter separated from the oil in a second centrifugation as described before.
    The oil produced by only physical (mechanical) means as described above is called virgin oil. Extra virgin olive oil is virgin olive oil that satisfies specific high chemical and organoleptic criteria (low free acidity, no or very little organoleptic defects).
  4. Sometimes the produced oil will be filtered to eliminate remaining solid particles that may reduce the shelf life of the product. Labels may indicate the fact that the oil has not been filtered, suggesting a different taste. Unfiltered fresh olive oil that has a slightly cloudy appearance is called cloudy olive oil
    Cloudy olive oil
    Cloudy olive oil is an intermediate product of olive oil extraction. It is actually the initial cloudy juice of the olive drupes soon after crushing, separation and decanting and before final filtration...

    . This form of olive oil used to be popular only among olive oil small scale producers but is now becoming "trendy", in line with consumer's demand for more ecological and less-processed "green" products.


The remaining paste (pomace) still contains a small quantity (about 5–10%) of oil that cannot be extracted by further pressing, but only with chemical solvents. This is done in specialised chemical plants, not in the oil mills. The resulting oil is not "virgin" but "pomace oil". The term "first press", sometimes found on bottle labels, is technically meaningless, as there is no "second" press.

The label term "cold-extraction" on extra virgin olive oils indicates that the olive grinding and stirring was done at a temperature of maximum 25 °C (77 °F), as treatment in higher temperatures risks decreasing the olive oils' quality (texture, taste and aroma).

Constituents

Olive oil is composed mainly of the mixed triglyceride esters of oleic acid
Oleic acid
Oleic acid is a monounsaturated omega-9 fatty acid found in various animal and vegetable fats. It has the formula CH37CH=CH7COOH. It is an odorless, colourless oil, although commercial samples may be yellowish. The trans isomer of oleic acid is called elaidic acid...

 and palmitic acid
Palmitic acid
Palmitic acid, or hexadecanoic acid in IUPAC nomenclature, is one of the most common saturated fatty acids found in animals and plants. Its molecular formula is CH314CO2H. As its name indicates, it is a major component of the oil from palm trees . Palmitate is a term for the salts and esters of...

 and of other fatty acid
Fatty acid
In chemistry, especially biochemistry, a fatty acid is a carboxylic acid with a long unbranched aliphatic tail , which is either saturated or unsaturated. Most naturally occurring fatty acids have a chain of an even number of carbon atoms, from 4 to 28. Fatty acids are usually derived from...

s, along with traces of squalene
Squalene
Squalene is a natural organic compound originally obtained for commercial purposes primarily from shark liver oil, though plant sources are used as well, including amaranth seed, rice bran, wheat germ, and olives. All plants and animals produce squalene, including humans...

 (up to 0.7%) and sterol
Sterol
Sterols, also known as steroid alcohols, are a subgroup of the steroids and an important class of organic molecules. They occur naturally in plants, animals, and fungi, with the most familiar type of animal sterol being cholesterol...

s (about 0.2% phytosterol
Phytosterol
Phytosterols, which encompass plant sterols and stanols, are steroid compounds similar to cholesterol which occur in plants and vary only in carbon side chains and/or presence or absence of a double bond. Stanols are saturated sterols, having no double bonds in the sterol ring structure. More than...

 and tocosterols). The composition varies by cultivar, region, altitude, time of harvest, and extraction process.

Olive oil contains a group of related natural product
Natural product
A natural product is a chemical compound or substance produced by a living organism - found in nature that usually has a pharmacological or biological activity for use in pharmaceutical drug discovery and drug design...

s with potent antioxidant
Antioxidant
An antioxidant is a molecule capable of inhibiting the oxidation of other molecules. Oxidation is a chemical reaction that transfers electrons or hydrogen from a substance to an oxidizing agent. Oxidation reactions can produce free radicals. In turn, these radicals can start chain reactions. When...

 properties that give extra-virgin unprocessed olive oil its bitter and pungent taste
Taste
Taste is one of the traditional five senses. It refers to the ability to detect the flavor of substances such as food, certain minerals, and poisons, etc....

 and are ester
Ester
Esters are chemical compounds derived by reacting an oxoacid with a hydroxyl compound such as an alcohol or phenol. Esters are usually derived from an inorganic acid or organic acid in which at least one -OH group is replaced by an -O-alkyl group, and most commonly from carboxylic acids and...

s of tyrosol
Tyrosol
Tyrosol is a natural phenolic antioxidant present in a variety of natural sources. The principal source in the human diet is olive oil. Tyrosol is a derivative of phenethyl alcoholAs an antioxidant, tyrosol can protect cells against injury due to oxidation...

 and hydroxytyrosol
Hydroxytyrosol
Hydroxytyrosol is a phytochemical with antioxidant properties. After gallic acid, hydroxytyrosol is believed to be one of the most powerful antioxidants...

, including oleocanthal
Oleocanthal
Oleocanthal is a natural organic compound isolated from extra virgin olive oil. It is responsible for the slightly peppery "bite" of extra virgin olive oil. Oleocanthal is a tyrosol ester and its chemical structure is related to oleuropein that is also found in olive oil.Oleocanthal has been found...

 and oleuropein
Oleuropein
Oleuropein is a chemical compound found in olive leaf from the olive tree together with other closely related compounds such as 10-hydroxyoleuropein, ligstroside, and 10-hydroxyligstroside. All these compounds are tyrosol esters of elenolic acid that are further hydroxylated and glycosylated...

.

Nutrition and health effects

Olive oil contains a wide variety of valuable antioxidants that are not found in other oils. Hydroxytyrosol
Hydroxytyrosol
Hydroxytyrosol is a phytochemical with antioxidant properties. After gallic acid, hydroxytyrosol is believed to be one of the most powerful antioxidants...

 is thought to be the main antioxidant compound in olives, and believed to play a significant role in the many health benefits attributed to olive oil. Epidemiological studies suggest that olive oil has a protective effect against certain malignant tumours in the breast, prostate, endometrium and digestive tract. Research has revealed that the type rather than the quantity of fat seems to have more implications for cancer incidence.

Evidence from epidemiological studies also suggests that a higher proportion of monounsaturated fat
Monounsaturated fat
In biochemistry and nutrition, monounsaturated fats or MUFA are fatty acids that have one double bond in the fatty acid chain and all of the remainder of the carbon atoms in the chain are single-bonded...

s in the diet is linked with a reduction in the risk of coronary heart disease
Coronary heart disease
Coronary artery disease is the end result of the accumulation of atheromatous plaques within the walls of the coronary arteries that supply the myocardium with oxygen and nutrients. It is sometimes also called coronary heart disease...

. This is significant because olive oil is considerably rich in monounsaturated fats, most notably oleic acid
Oleic acid
Oleic acid is a monounsaturated omega-9 fatty acid found in various animal and vegetable fats. It has the formula CH37CH=CH7COOH. It is an odorless, colourless oil, although commercial samples may be yellowish. The trans isomer of oleic acid is called elaidic acid...

.

In the United States, producers of olive oil may place the following health claim on product labels:
Limited and not conclusive scientific evidence suggests that eating about 2 tbsp.
Tablespoon
A tablespoon is a type of large spoon usually used for serving. A tablespoonful, the capacity of one tablespoon, is commonly used as a measure of volume in cooking...

 (23 g) of olive oil daily may reduce the risk of coronary heart disease due to the monounsaturated fat in olive oil. To achieve this possible benefit, olive oil is to replace a similar amount of saturated fat
Saturated fat
Saturated fat is fat that consists of triglycerides containing only saturated fatty acids. Saturated fatty acids have no double bonds between the individual carbon atoms of the fatty acid chain. That is, the chain of carbon atoms is fully "saturated" with hydrogen atoms...

 and not increase the total number of calories you eat in a day.


This decision was announced November 1, 2004, by the Food and Drug Administration after application was made to the FDA by producers. Similar labels are permitted for foods rich in omega-3 fatty acid
Omega-3 fatty acid
N−3 fatty acids are essential unsaturated fatty acids with a double bond starting after the third carbon atom from the end of the carbon chain....

s such as Almond
Almond
The almond , is a species of tree native to the Middle East and South Asia. Almond is also the name of the edible and widely cultivated seed of this tree...

s and hemp
Hemp
Hemp is mostly used as a name for low tetrahydrocannabinol strains of the plant Cannabis sativa, of fiber and/or oilseed varieties. In modern times, hemp has been used for industrial purposes including paper, textiles, biodegradable plastics, construction, health food and fuel with modest...

 seed.

There is a large body of clinical data to show that consumption of olive oil can provide heart health benefits such as favourable effects on cholesterol
Cholesterol
Cholesterol is a complex isoprenoid. Specifically, it is a waxy steroid of fat that is produced in the liver or intestines. It is used to produce hormones and cell membranes and is transported in the blood plasma of all mammals. It is an essential structural component of mammalian cell membranes...

 regulation and LDL cholesterol oxidation, and that it exerts antiinflamatory, antithrombotic, antihypertensive as well as vasodilatory effects both in animals and in humans. Additionally, Olive oil protects against heart disease as it controls the "bad" levels of LDL cholesterol and raises levels of the "good" cholesterol, HDL.

As they are the least processed forms of olive oil, extra virgin or virgin olive oil have more monounsaturated fatty acids than other olive oil. These types also contain more polyphenols, which may have benefits for the heart.

1tbsp of olive oil (13.5g) contains the following nutritional information according to the USDA:
  • Calories : 119
  • Fat: 13.50
  • Carbohydrates: 0
  • Fibers: 0
  • Protein: 0

Phenolic content

Some clinical evidence suggests that it is olive oil's phenolic
Natural phenol
Natural phenols, bioavailable phenols, plant phenolics, low molecular weight phenols or phenoloids are a class of natural products. They are small molecules containing one or more phenolic group. These molecules are smaller in size than polyphenols, containing less than 12 phenolic groups...

 content, rather than its fatty acid profile, that is responsible for at least some of its cardioprotective benefits. For example, a clinical trial published in 2005 compared the effects of different types of olive oil on arterial elasticity. Test subjects were given a serving of 60 g of white bread and 40 ml of olive oil each morning for two consecutive days. The study was conducted in two stages. During the first stage, the subjects received polyphenol-rich oil (extra virgin oil contains the highest amount of polyphenol antioxidant
Polyphenol antioxidant
A polyphenol antioxidant is a type of antioxidant containing a polyphenolic substructure. Numbering over 4,000 distinct species, many of these compounds have antioxidant activity in vitro but are unlikely to have antioxidant roles in vivo...

s like oleuropein
Oleuropein
Oleuropein is a chemical compound found in olive leaf from the olive tree together with other closely related compounds such as 10-hydroxyoleuropein, ligstroside, and 10-hydroxyligstroside. All these compounds are tyrosol esters of elenolic acid that are further hydroxylated and glycosylated...

 or tyrosol
Tyrosol
Tyrosol is a natural phenolic antioxidant present in a variety of natural sources. The principal source in the human diet is olive oil. Tyrosol is a derivative of phenethyl alcoholAs an antioxidant, tyrosol can protect cells against injury due to oxidation...

). During the second phase, they received oil with only one fifth the phenolic content. The elasticity of the arterial walls of each subject was measured using a pressure sleeve and a Doppler
Doppler effect
The Doppler effect , named after Austrian physicist Christian Doppler who proposed it in 1842 in Prague, is the change in frequency of a wave for an observer moving relative to the source of the wave. It is commonly heard when a vehicle sounding a siren or horn approaches, passes, and recedes from...

 laser
Laser
A laser is a device that emits light through a process of optical amplification based on the stimulated emission of photons. The term "laser" originated as an acronym for Light Amplification by Stimulated Emission of Radiation...

. It was discovered that after the subjects had consumed olive oil high in polyphenol antioxidants, they exhibited increased arterial elasticity, while after the consumption of olive oil containing fewer polyphenols, they displayed no significant change in arterial elasticity. It is theorized that, in the long term, increased elasticity of arterial walls reduces vascular stress and consequentially the risk of two common causes of death—heart attacks
Myocardial infarction
Myocardial infarction or acute myocardial infarction , commonly known as a heart attack, results from the interruption of blood supply to a part of the heart, causing heart cells to die...

 and stroke
Stroke
A stroke, previously known medically as a cerebrovascular accident , is the rapidly developing loss of brain function due to disturbance in the blood supply to the brain. This can be due to ischemia caused by blockage , or a hemorrhage...

. This could, at least in part, explain the lower incidence of both diseases in regions where olive oil and olives are consumed on a daily basis.

Skin care

In addition to the internal health benefits of olive oil, topical application is quite popular with fans of natural health remedies. Extra virgin olive oil is the preferred grade for moisturizing the skin, especially when used in the oil cleansing method
Oil cleansing method
The oil cleansing method, often abbreviated to OCM, is a system for cleaning a human face using oils. The basic method uses a mixture of 80% extra virgin olive oil and 20% castor oil. The mixture can be optimized based on skin type and personal preference. Oily skin can make use of a larger...

 (OCM). OCM is a method of cleansing and moisturizing the face with a mixture of extra virgin olive oil, castor oil (or another suitable carrier oil) and a select blend of essential oils. Olive oil has been known for generations not only for its healing qualities but also as a natural, deep penetration moisturizer, regenerating skin cells and softening the tissue. Olive oil is also used by some to reduce ear wax buildup.

Olive oil can be used as an effective shaving oil
Shaving oil
Shaving oil is normally a plant-based oil or blend of vegetable and essential oils used as a stand-alone shave lubricant or in conjunction with shave creme, soap or gel, to facilitate the shave of facial and other body hair. Often these products require activation with water before the razor is...

 to shave facial and other body hair.

Studies on mice showed that application of olive oil immediately following exposure to UVB rays has a preventive effect on the formation of tumors and skin cancer
Skin cancer
Skin neoplasms are skin growths with differing causes and varying degrees of malignancy. The three most common malignant skin cancers are basal cell cancer, squamous cell cancer, and melanoma, each of which is named after the type of skin cell from which it arises...

.

It is also widely used in cosmetics, soaps and are immensely beneficial in adding smoothness and softness to dry scaly skins especially during winter seasons.

Medicinal use

Olive oil is unlikely to cause allergic reactions
Allergy
An Allergy is a hypersensitivity disorder of the immune system. Allergic reactions occur when a person's immune system reacts to normally harmless substances in the environment. A substance that causes a reaction is called an allergen. These reactions are acquired, predictable, and rapid...

, and as such is used in preparations for lipophilic
Lipophilic
Lipophilicity, , refers to the ability of a chemical compound to dissolve in fats, oils, lipids, and non-polar solvents such as hexane or toluene. These non-polar solvents are themselves lipophilic — the axiom that like dissolves like generally holds true...

 drug ingredients. It does have demulcent
Demulcent
A demulcent is an agent that forms a soothing film over a mucous membrane, relieving minor pain and inflammation of the membrane. Demulcents are sometimes referred to as mucoprotective agents. Demulcents such as pectin, glycerin, honey, and syrup are common ingredients in cough mixtures...

 properties, and mild laxative
Laxative
Laxatives are foods, compounds, or drugs taken to induce bowel movements or to loosen the stool, most often taken to treat constipation. Certain stimulant, lubricant, and saline laxatives are used to evacuate the colon for rectal and/or bowel examinations, and may be supplemented by enemas under...

 properties, acting as a stool softener. It is also used at room temperature as an ear wax softener.
Olive oil is also a potent blocker of intestinal contractions, and can be used to treat excessive Borborygmus
Borborygmus
Borborygmus also known as stomach growling, rumbling, gurgling, grumbling or wambling, is the rumbling sound produced by the contraction of muscles in the stomach and intestines of animals, including humans...

.

Oleocanthal
Oleocanthal
Oleocanthal is a natural organic compound isolated from extra virgin olive oil. It is responsible for the slightly peppery "bite" of extra virgin olive oil. Oleocanthal is a tyrosol ester and its chemical structure is related to oleuropein that is also found in olive oil.Oleocanthal has been found...

 from olive oil is a non-selective inhibitor of cyclooxygenase
Cyclooxygenase
Cyclooxygenase is an enzyme that is responsible for formation of important biological mediators called prostanoids, including prostaglandins, prostacyclin and thromboxane. Pharmacological inhibition of COX can provide relief from the symptoms of inflammation and pain...

 (COX) similar to classical NSAIDs like ibuprofen
Ibuprofen
Ibuprofen is a nonsteroidal anti-inflammatory drug used for relief of symptoms of arthritis, fever, as an analgesic , especially where there is an inflammatory component, and dysmenorrhea....

. It has been suggested that long-term consumption of small quantities of this compound from olive oil may be responsible in part for the low incidence of heart disease
Heart disease
Heart disease, cardiac disease or cardiopathy is an umbrella term for a variety of diseases affecting the heart. , it is the leading cause of death in the United States, England, Canada and Wales, accounting for 25.4% of the total deaths in the United States.-Types:-Coronary heart disease:Coronary...

 associated with a Mediterranean diet
Mediterranean diet
The Mediterranean diet is a modern nutritional recommendation inspired by the traditional dietary patterns of southern Italy, Crete and much of the rest of Greece in the 1960s....

.

Other

Another health benefit of olive oil seems to be its property to displace omega-6 fatty acid
Omega-6 fatty acid
n−6 fatty acids are a family of unsaturated fatty acids that have in common a final carbon–carbon double bond in the n−6 position, that is, the sixth bond, counting from the methyl end.The biological effects of the n−6 fatty acids are largely mediated by their conversion to n-6 eicosanoids...

s, while not having any impact on omega-3 fatty acid
Omega-3 fatty acid
N−3 fatty acids are essential unsaturated fatty acids with a double bond starting after the third carbon atom from the end of the carbon chain....

s. This way, olive oil helps to build a more healthy balance between omega-6 fats and omega-3 fats.

Unlike saturated fats, olive oil lowers total cholesterol and LDL levels in the blood. It is also known to lower blood sugar
Blood sugar
The blood sugar concentration or blood glucose level is the amount of glucose present in the blood of a human or animal. Normally in mammals, the body maintains the blood glucose level at a reference range between about 3.6 and 5.8 mM , or 64.8 and 104.4 mg/dL...

 levels and blood pressure.

Olive oil contains the monounsaturated fatty acid oleic acid
Oleic acid
Oleic acid is a monounsaturated omega-9 fatty acid found in various animal and vegetable fats. It has the formula CH37CH=CH7COOH. It is an odorless, colourless oil, although commercial samples may be yellowish. The trans isomer of oleic acid is called elaidic acid...

, antioxidants such as vitamin E
Vitamin E
Vitamin E is used to refer to a group of fat-soluble compounds that include both tocopherols and tocotrienols. There are many different forms of vitamin E, of which γ-tocopherol is the most common in the North American diet. γ-Tocopherol can be found in corn oil, soybean oil, margarine and dressings...

 and carotenoids, and oleuropein
Oleuropein
Oleuropein is a chemical compound found in olive leaf from the olive tree together with other closely related compounds such as 10-hydroxyoleuropein, ligstroside, and 10-hydroxyligstroside. All these compounds are tyrosol esters of elenolic acid that are further hydroxylated and glycosylated...

, a chemical that may help prevent the oxidation of LDL particles.

Preliminary research indicates that olive oil could possibly be a chemopreventive agent for peptic ulcer
Peptic ulcer
A peptic ulcer, also known as PUD or peptic ulcer disease, is the most common ulcer of an area of the gastrointestinal tract that is usually acidic and thus extremely painful. It is defined as mucosal erosions equal to or greater than 0.5 cm...

 or gastric cancer, but confirmation requires further in vivo study."New Potential Health Benefit Of Olive Oil For Peptic Ulcer Disease." ScienceDaily 14 February 2007 Olive oil was also found to reduce oxidative damage to DNA and RNA, which may be a factor in preventing cancer."New Year's Resolution No. 1: Prevent Cancer, Use Olive Oil." ScienceDaily 12 December 2006.

Unsaturated oils, such as olive oil, have a short shelf life and are prone to becoming rancid from oxidation, which will produce toxic byproducts and a bitter taste. Protection of unsaturated oils from heat and light will delay spoilage.

Uses

Culinary use

Olive oil is the main cooking oil in countries surrounding the Mediterranean Sea.

Extra virgin olive oil is mostly used as a salad dressing and as an ingredient in salad dressings. It is also used with foods to be eaten cold. If uncompromised by heat, the flavor is stronger. It also can be used for sautéing
Sautéing
Sautéing is a method of cooking food, that uses a small amount of fat in a shallow pan over relatively high heat. Ingredients are usually cut into pieces or thinly sliced to facilitate fast cooking. The primary mode of heat transfer during sautéing is conduction between the pan and the food being...

.

The higher the temperature to which the olive oil is heated, the more one should prefer the use of refined olive oils. When extra virgin olive oil is heated above 350 °F (176.7 °C), the unrefined particles within the oil are burned. This leads to deteriorated taste. Also, the pronounced taste of extra virgin olive oil is not a taste most people like to associate with their deep fried foods. Refined olive oils are perfectly suited for deep frying
Deep frying
Deep frying is a cooking method in which food is submerged in hot oil or fat. This is normally performed with a deep fryer or chip pan; industrially, a pressure fryer or vacuum fryer may be used....

 foods and should be replaced after several uses.

Choosing a cold-pressed olive oil can be similar to selecting a wine
Wine
Wine is an alcoholic beverage, made of fermented fruit juice, usually from grapes. The natural chemical balance of grapes lets them ferment without the addition of sugars, acids, enzymes, or other nutrients. Grape wine is produced by fermenting crushed grapes using various types of yeast. Yeast...

. The flavour of these oils varies considerably and a particular oil may be more suited for a particular dish. Also, people who like lots of tannins in their red wines might prefer more bitter olive oils.

An important issue often not realized in countries that do not produce olive oil is that the freshness makes a big difference. A very fresh oil, as available in an oil producing region, tastes noticeably different from the older oils available elsewhere. In time, oils deteriorate and become stale. One-year old oil may be still pleasant to the taste, but it is surely less fragrant than fresh oil. After the first year, olive oil should be used for cooking, not for foods to be eaten cold, like salads.

The taste of the olive oil is influenced by the varietals used to produce the oil from and by the moment when the olives are harvested and ground (less ripe olives give more bitter and spicy flavors, which is a positive attribute - riper olives give a sweeter sensation in the oil).

Olive oil has more uses than as food; it also works as a natural and safe lubricant, such as lubricating the machinery that is used within the kitchen (grinders, blenders, cookware, etc.)
The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
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