The olive (Olea europea) was first cultivated in Crete 5000 years ago and ever since, olive and its oil have been a nutritional staple to flavor and prepare food.
Olive oil is the only oil obtained from the fruit of the plant rather than its seed.
Oils that are derived from the seeds of the plant, require extensive refining. This process makes them non-toxic and safe but also removes its important phytochemicals.
Some of these compounds protect the developing plant embryo from free radical attack.
The olive in particular is high in tocopherols (vitamin E) and polyphenols. These compounds also protect the extracted oil from oxidation after processing.
Olives and its oil are a nutritional treasure chest filled with a library of important phytochemicals. The full spectrum of compounds are found in the whole fruit and unfiltered oil. Refining removes them.
Olive oil is the primary source of fat in the Mediterranean diet and is high in high monounsaturated fat and rich in antioxidants. Olive oil has a long shelf life and like all oils contains 14 grams of fat per tablespoon, which provides 120 calories. Since olive oil provides such a strong and distinct flavor, less is needed to flavor food.
The chemical characteristics of olive oil is the consequence of the phytochemicals left in the oil. The more that remain of the whole fruit, the better tasting and healthier the oil.
Unfiltered, stone pressed olive oil has small bits of olive in it. These olive fragments retain the natural antioxidants and olive polyphenols (3, 4-dihydroxyphenyl ethanol, hydroxytyrosol and tyrosol) contained in the whole olive.
Olive oil is recommended as a substitute for all other fats whenever possible.
Olive oil extraction crushes the fruit of the olive to obtain its oil. The freshness and chemical uniqueness of olive oil is maintained only when it is milled and pressed within twenty-four hours of being picked. Consumers are unaware of these practices and can’t determine if those conditions are met. Buying from quality olive oil manufacturers is the only way to ensure that freshness.oils Sediment deposited at the bottom of the container is a sign of good, unfiltered olive oil.
The first pressing of the olives is the highest in quality. The quicker the picked olive’s oil is extracted, the healthier the oil will be. Less oxidation produces better oil.
Olives are first washed with water to remove any impurities on its skin and then crushed to a paste. This begins the extraction process. The traditional cold squeezing breaks the olive’s pulp by employing two turning granite wheels. Since there is no heat involved it is known as cold pressing.
The first cold pressing produces the most flavorful and healthiest oils. Warm squeezing is the modern method. The pulp is heated and then centrifuged to separate the oil from the solid residue. Commercial centrifugation generates heat as it removes water from the olive dough. This heat alters the phytochemical properties of the oil and make it more susceptible to free radical attack.
Refrigeration does not alter or damage extra virgin olive oil but it does cause fat droplets to coalesce. Solid block formation during refrigeration is an indication of a poor olive oil.
Olive oil is bottled in dark colored glass bottles and tin cans to protect it from the sun’s ray and oxidation. Large containers of olive oil should be stored in a cool, dark room. Cruets containing olive oil should be closed and constantly refilled to minimize the amount of space that oxygen can occupy. This prevents the oil’s oxidation.
Classification of Olive Oils
The classification of olive oil is based on the amount of acidic fats in the oil and varies based on climate, pressing technique, and the length of time between picking and pressing. Acidity is a reflection of the amount of oleic acid in the oil, which is also affected by the quality of the olives and the manner in which they are harvested. The more acidic the oil, the more it can withstand high temperatures.
A good quality olive oil retains much of the flavor of the fruit of the olive. The best ones are stone pressed and unfiltered. The more refined the oil, the more the oil loses flavor and taste.
The more fruity and aromatic the oil, the greater is its nutritional value.
1. Extra Virgin Olive Oil has an acidity level of 1% or less. Acidity is a function of oleic acid concentration. Extra Virgin is the healthiest and tastiest form of olive oil. It is not a good oil to cook with since its smoke point is around 370 degrees.
2. Soprafino Virgin Olive Oil is 2% acidic. 400 degree SP
3. Fino Virgin Olive Oil is produced by industrial refining and is even more acidic with up to 3 % acid and a SP of 420
4. Virgin Olive oil is a light colored oil that contains 4% acid.
Sansa (Pomace) is highly refined oil that is obtained by solvents used to dissolve the pulpy residue (sansa). The sansa still contains oil but requires more extensive processes to extract it. The resulting oil contains more than 4% acidic components and many chemical imperfections. Since the refined oil is devoid of flavor and taste, it is often blended with Extra Virgin oil to lend flavor to the oil and makes a good choice for high temperature cooking.
The Food and Drug Administration now permits food manufacturers to claim that olive oil can reduce the risk of coronary heart disease due to its monounsaturated fat content.
Extra-virgin olive oil is the least acidic of the olive oils. The best extra-virgin olive oil contains less that 1% free acid. Acidity lends a sensation of sourness to the oil. The less free fatty acids in the oil, the better the tasting oil. Extra-virgin olive oil is much less acidic than virgin olive oil. The more an oil is refined, the higher its oleic acid content.
Differences in extra virgin batches are due to the region and climate where the olives were cultivated. The type of olive and the manner in which the olives are harvested provide other flavor differences.
Virgin olive oil is the most common olive oil found in supermarkets. They are good oils for light cooking. Virgin olive oil lacks the flavor, aroma and phytopigments of extra virgin but is more heat resistant.
Extra light and light olive oils are more refined, have less taste and phytochemicals but still retains the calories of the more pigmented extra virgin. These light olive oils are even more heat resistant and make a better choice for cooking.
Extra virgin olive oil is the preferred type since it contains all the unaltered phytochemicals, nutrients, flavors and aromas of the whole olive. These compounds give olive oil its distinctive fruity flavor and provides important health benefits.
The health benefits attributed to olive oil include an improved lipid profile and lower cholesterol levels. It is also thought to prevent cancer though its library of olive polyphenols, flavonoids and tocopherols..