Olive oil

Olive oil is a vegetable oil obtained by pressing whole olives (the fruit of Olea europaea, a traditional tree crop of the Mediterranean Basin) and extracting the oil.

It is commonly used in cooking for frying foods, as a condiment, or as a salad dressing. It can also be found in some cosmetics, pharmaceuticals, soaps, and fuels for traditional oil lamps. It also has additional uses in some religions. The olive is one of three core food plants in Mediterranean cuisine, with wheat and grapes. Olive trees have been cultivated around the Mediterranean since the 8th millennium BC.

In 2022, Spain was the world's largest producer, manufacturing 24% of the world's total. Other large producers were Italy, Greece, and Turkey, collectively accounting for 59% of the global market.

The composition of olive oil varies with the cultivar, altitude, time of harvest, and extraction process. It consists mainly of oleic acid (up to 83%), with smaller amounts of other fatty acids including linoleic acid (up to 21%) and palmitic acid (up to 20%). Extra virgin olive oil (EVOO) is required to have no more than 0.8% free acidity, and is considered to have favorable flavor characteristics.

History

Olive oil has long been a common ingredient in Mediterranean cuisine, including ancient Greek and Roman cuisine. Wild olives, which originated in Asia Minor, were collected by Neolithic people as early as the 8th millennium BC. Besides food, olive oil has been used for religious rituals, medicines, as a fuel in oil lamps, soap-making, and skincare application. The Spartans and other Greeks used oil to rub themselves while exercising in the gymnasia. From its beginnings early in the 7th century BC, the cosmetic use of olive oil quickly spread to all of the Hellenic city-states, together with athletes training in the nude, and lasted close to a thousand years despite its great expense. Olive oil was also popular as a form of birth control; Aristotle in his History of Animals recommends applying a mixture of olive oil combined with either oil of cedar, ointment of lead, or ointment of frankincense to the cervix to prevent pregnancy.

Early cultivation

The exact date and location of olive tree domestication are unclear. The modern olive tree may have originated in ancient Persia and Mesopotamia and spread to the Levant and later to North Africa, though some scholars argue for an Egyptian origin.

The oldest traces of olive oil in Italy date back to the 3rd millennium BC. The olive tree reached Greece, Carthage and Libya sometime in the 28th century BC, having been spread westward by the Phoenicians. Until around 1500 BC, eastern coastal areas of the Mediterranean were most heavily cultivated. Evidence also suggests that olives were being grown in Crete as long ago as 2500 BC. The earliest surviving olive oil amphorae date to 3500 BC (Early Minoan times), though the production of olive oil is assumed to have started before 4000 BC. 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, as it did across the Mediterranean. Later, as Greek colonies were established in other parts of the Mediterranean, olive farming was introduced to places like Spain and continued to spread throughout the Roman Empire.

Olive trees were introduced to the Americas in the 16th century, when cultivation began in areas with a climate similar to the Mediterranean, such as Chile, Argentina, and California.

Recent genetic studies suggest that species used by modern cultivars descend from multiple wild populations, but detailed history of domestication is unknown.;

Trade and production

Archaeological evidence in Galilee shows that by 6000 BC olives were being turned into olive oil and in 4500 BC at a now-submerged prehistoric settlement south of Haifa.

Olive trees and oil production in the Eastern Mediterranean can be traced to archives of the ancient city-state Ebla (2600–2240 BC), which were located on the outskirts of Aleppo. Here, some dozen documents dated 2400 BC describe the 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 the Tanakh.

Dynastic Egyptians before 2000 BC imported olive oil from Crete, Syria, and Canaan, 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. Sinuhe, the Egyptian exile who lived in northern Canaan c.1960 BC, wrote of abundant olive trees. The Minoans used olive oil in religious ceremonies. The oil became a principal product of the Minoan civilization, where it is thought to have represented wealth.

Olive oil was also a major export of Mycenaean Greece (c. 1450–1150 BC). Scholars believe the oil was made by a process where olives were placed in woven mats and squeezed. The oil was collected in vats. This process was known from the Bronze Age, was used by the Egyptians, and continued to be used through the Hellenistic period. In the Iron Age, settlements in and around the Judaean Lowlands, including Ekron, Timnah, and Gezer, emerged as key hubs for olive oil production and commerce. Evidence from the Samaria Ostraca, discovered in the capital of the Kingdom of Israel, includes a reference to "washed oil," a term believed to refer to virgin olive oil.

Olive oil may have been produced as early as the Bronze Age in Italy, though this intensified throughout the first millennium BCE and into the Roman period. Some of the earliest evidence of rotary olive mills for the production of olive oil have been found in southern Italy. The importance of olive oil as a commercial commodity increased after the Roman conquest of Egypt, Greece, and Asia Minor, which led to more trade along the Mediterranean. Olive trees were planted throughout the entire Mediterranean basin during the evolution of the Roman Republic and Empire. According to the historian Pliny the Elder, Italy had "excellent olive oil at reasonable prices" by the 1st century AD—"the best in the Mediterranean". More sophisticated production techniques such as the olive press and trapetum (pictured left) became increasingly widespread throughout the Imperial era, and eventually screw presses were commonly used to produce olive oil from Spain to the eastern Mediterranean. Many ancient presses still exist in the Eastern Mediterranean region, and some dating to the Roman period are still used today. Productivity was greatly improved by Joseph Graham's development of the hydraulic pressing system in 1795.

Symbolism and mythology The olive tree has historically been a symbol of peace between nations. It has played a religious and social role in Greek mythology, especially concerning the city of Athens, named after the goddess Athena because her gift of an olive tree was held to be more precious than rival Poseidon's gift of a salt spring.

Varieties

There are many olive cultivars, each with a particular flavor, texture, and shelf life that make them more or less suitable for different applications, such as direct human consumption on bread or in salads, indirect consumption in domestic cooking or catering, or industrial uses such as animal feed or engineering applications. During the stages of maturity, olive fruit changes color from green to violet, and then black. Olive oil taste characteristics depend on the stage of ripeness at which olive fruits are collected.

Uses Culinary use

Olive oil is an important cooking oil in countries surrounding the Mediterranean, and it forms one of the three staple food plants of Mediterranean cuisine, the other two being wheat (as in pasta, bread, and couscous), and the grape, used as a dessert fruit and for wine.

Extra virgin olive oil is mostly used raw as a condiment and as an ingredient in salad dressings. If uncompromised by heat, the flavor is stronger. It can also be used for sautéing.

When extra virgin olive oil is heated above , depending on its free fatty acid content, the unrefined particles within the oil are burned. This leads to a deteriorated taste. Refined olive oils are suited for deep frying because of the higher smoke point and milder flavour. Extra virgin oils have a smoke point around , with higher-quality oils having a higher smoke point, whereas refined light olive oil has a smoke point up to . That they can be used for deep frying is contrary to the common misconception that there are no olive oils with a smoke point as high as many other vegetable oils. In the misconception, heating at these high temperatures is theorised to impact taste or nutrition.

Religious use

Christianity

Various Christian churches use olive oil as part of consecration ceremonies, such as administering certain sacraments and ecclesiastical functions. The Church of Jesus Christ of Latter-day Saints uses pure olive oil that the priesthood has blessed (consecrated) for anointing the sick.

Judaism

In Jewish observance, olive oil was the only fuel permitted for use in the seven-branched menorah used in the service of the Mishkan the Exodus of the Tribes of Israel from Egypt, and later in the permanent Temple in Jerusalem. According to biblical law, the oil used for the menorah had to be pure olive oil produced by the first pressing of the olives, traditionally obtained by gently crushing them so that only the first oil was collected.

Olive oil plays a central role in the story of Hanukkah, which commemorates the rededication of the Temple following the Maccabean Revolt. According to Jewish tradition, a single cruse of consecrated oil, enough for one day, miraculously burned for eight days in the Temple menorah. In modern observance of Hanukkah, candles are commonly used to light the Hanukkah menorah, though olive oil lamps are often preferred by some communities in order to more closely replicate the original Temple practice.Babylonian Talmud, Menachot 85b

In ancient Israelite religion, olive oil was a key ingredient in the sacred holy anointing oil described in the Hebrew Bible. This oil was used to ritually consecrate priests, kings, prophets, and sacred objects, symbolizing divine selection and sanctification.Eisenberg, Ronald L. Dictionary of Jewish Terms: A Guide to the Language of Judaism, , 2011, p. 299.

Islam

Olive oil is used in Islam for both spiritual and practical purposes, with guidance found in the Qur'an, Sunnah and traditional prophetic medicine. In Sura At- Tin; Chapter 95 of Al Qur'an Allah swears by Olives and Figs. Furthermore, An- Nur (24:35) uses Olive oil as a symbol of divine light representing its spiritual significance in Islam. Allah says, "And [we brought forward a tree] issuing from Mount Sinai which produces oil and Food [i.e olive] for those who eat."(Al Qur'an 23:20) Moreover Prophet Muhammad has emphasized benefits of olive oil highlighting role in nutritional and external benefits of human body. He said, "Eat the oil (olive) and use it on your skin and hair, for it comes from the blessed tree"(tirmidhi). Olive oil is used as a medium for Ruqyah. Some scholars and practitioners recommend reciting Qur'an and then applying or ingesting it as a part of Ruqyah. Olive oil is given as charity, especially around Ramadan.

Extraction

Olive oil is produced by grinding ripe olives and extracting the oil by mechanical or chemical means. Underripe olives usually produce undesirably bitter oil, and overripe olives can produce oil with fermentation defects. The process is generally as follows:

The olives are ground into paste, traditionally by large millstones, or by modern hammer, blade, or disk mill.