Olive oil is the oil that comes from the fruits of the olive tree. Virgin olive oil is produced through the mechanical processing of the olive fruit in olive mills and is a key element of the Mediterranean diet and is considered a healthy food product due to its content of monounsaturated fats, antioxidant substances.
As for its production and processing, the olives are harvested by hand or by shaking the tree with sticks or by machines. Then, the olive fruit is transferred to the olive mill, to avoid fermentation and the growth of mold that degrades the quality of the olive oil. After weighing and sorting, the olives are placed in crates or sacks and with the help of elevators, they are transported into a large basin. This is followed by the kneading of the olive pulp, with stirring for half an hour or an hour in devices called “mushers”. For good quality olive oil, the kneading is done “cold”, i.e. at room temperature. Then, with the help of powerful hydraulic presses, the olive liquids are extracted, which is a mixture of olive oil and watery components of the fruit. In modern oil mills, the separation of liquids from solids is done by centrifugation in devices called “decanters”. The solid by-product that remains is called the “core”. In the oil mills there are also tanks where the scum and the water used to wash the oils are collected. The liquid waste from the olive mills (also known as “catsigaros”) used to be discharged into the environment, which is why most olive mills were located near streams or even near the sea.
Solid waste is commonly called “kernel” or “cob”. The kernel contains a significant amount of olive oil which is obtained by physicochemical methods in kernel oil mills. In order to become edible, it is refined or “refined” in special factories called “refineries”. Refining is an intense chemical process that destroys much of the flavor, aroma and some useful nutrients in olive oil. Commercially available olive oils are divided into edible and industrial oils. The former are basically divided into virgin olive oils and simple olive oils.
Olive oil is more than a rich source of monounsaturated fatty acids. Its phenolic components have shown anti-inflammatory and chemo-protective properties. In fact, research has shown that Greece has the highest consumption of olive oil per person in the world. But what are the health benefits of olive oil?
Olive oil is the main source of dietary fat in the Mediterranean diet, which is associated with a low death rate from cardiovascular disease compared to other parts of the world. People who regularly consume olive oil are much less likely to develop cardiovascular diseases, such as hypertension (high blood pressure), stroke, and hyperlipidemia (high cholesterol and triglyceride levels). According to other research, regular intake of olive oil helps reduce inflammation, endothelial dysfunction (problems in the inner walls of blood vessels), thrombosis and carbohydrate metabolism.
Additionally, olive oil consumption could help explain the low rate of cardiovascular mortality in Southern European and Mediterranean countries, compared to other Western countries, despite the high prevalence of high risk for coronary heart disease. Those who regularly consume food fried in olive oil do not have a higher risk of heart disease or early death, researchers from the Autonomous University of Madrid in Spain reported in the BMJ.
Olive oil helps prevent stroke. In a study by the University of Bordeaux and the National Institute of Health and Medical Research, it appeared that elderly people who regularly used olive oil for cooking and salad or in bread had a 41% lower risk of stroke, compared to their peers, who they never consumed olive oil.
Olive oil consumption was also associated with a lower risk of overt depression. According to a study conducted at the University of Las Palmas de Gran Canaria in Spain and published in PLoS ONE, olive oil appears to have a slight protective effect on the risk of depression.
Finally, it has been found to have anti-cancer properties. A recent study found that people who include olive oil in their diet face a lower risk of cancer. This is due to the high content of olive oil in oleic acid, which is the main fat contained in this food. In addition, olive oil contains antioxidants, flavonoids, polyphenols and squalene, all of which play an important role in its beneficial effect.