Olive Oil: One of the World's Oldest Lubricants

P.G. Adriani; A. Paccagnini, Mecoil

Olive oil remains one of the best and most popular condiments. Perfect for any fresh salad or pasta dish, it is very healthy and rich in natural ingredients. Derived from black, ripened olives, olive oil is considered one of the last “fruits” harvested right before early winter’s frost. Among its precious “additives” are antioxidants like vitamin A, D and E, as well as tocopherol and polyunsaturated fatty acid. These act as detergents for the human body’s blood vessels, protecting against strokes, accumulation of saturated animal greases and cholesterol-clogged arteries.

This shrub represents the original wild form
of the olive tree, with small branches and a
few thorns but no fruit.

Geographically, olive trees are distributed all across the Mediterranean basin. In this area, you can still find the original plants, which look like wild shrubs with small, silver leaves and a few thorns. They typically grow on rocky cliffs facing the seashore.

A Brief History of Olive Oil

Throughout history, the Phoenicians, Egyptians, Greeks and Romans used olive oil for a variety of purposes. It was a dietary staple rich in fat-soluble vitamins and calories when most diets were primarily based on cereals, a few fish or other meats, as well as some vegetables and seasonal fruits.

At night, the oil’s “energy” became an incredible resource, when clay lamps could enlighten the environment with only a few drops of this “holy” fluid. It was also one of the very first anti-friction fluids, employed not just for primitive machinery lubrication but to protect human bodies from abrasions during fighting contests.

Unfortunately, the oil’s flavor, taste and most vitamins are easily corrupted by thermal stress and light interferences. If not properly stored, the original emerald-green color of freshly squeezed olive oil turns into a stinky, yellowish fluid with no redeeming qualities. When this occurs, the oil is only fit for burning.

As the neutralization number slowly drifts toward high acidity, the flavor no longer reminds you of the fresh, crisp taste of “bruschetta,” the traditional roasted bread soaked in extra-virgin olive oil. You can often see sludge settling out of the oil in the bottom of a glass jar.

Since the Roman age, olive oil has been stored
in large clay jars. These “ziri” or “doli” drums
were positioned underground to maintain
a low temperature during summer.

A rotating pressure vessel oxidation test (RPVOT) is not necessary to determine if a particular bottle of olive oil is still good for your favorite dishes or is simply too aged. Your nose and mouth can give you the proper answer.

New Handling Approaches

New approaches, supported by modern technology, are changing the way the “green gold” is handled in order to maintain its original appeal. Special treatment is now used from the very beginning of the squeezing process inside the “frantoio.” This building is where tradition requires that all olives from the surrounding area are collected immediately and processed in the proper manner.

While the process temperature should be kept as low as possible, it is also important to keep in mind that the viscosity will affect the water separation process. Consider that only 12 to 14 percent of the total weight of the olives crushed during the process becomes edible oil. This is why it is so precious and expensive. By filtering immediately after the treatment with a good beta ratio and removing oxygen from the top of the jars by filling them with nitrogen gas, you can significantly extend the “useful life” of this precious green juice.

Some larger olive trees may be 80 years old.

Today, you can find a wide variety of local olive tree breeding, depending on the quality of the soil, climate and approach for taking care of these trees, which have become a dominant part of the Mediterranean landscape, from Portugal to Turkey. Scores of these giant trees, many centuries old, can still be seen in secluded missions in Southern California and Mexico, brought to the New World by the first European immigrants.

Cultural Roots

In our fast-changing world where a “just-in-time” approach is key to staying in business, remember that when you plant an olive tree, you likely will never get the chance to harvest its olives. Industry 4.0 and all its related processes may help in the marketing, distribution and handling of this old-fashioned product, but its intimate appeal will remain intact only as long as people maintain some of the cultural roots anchored to their heritage.

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