Acidity in the olive oil Istituto Comprensivo Milena-Campofranco ITALIA Comenius Project

The acidity in the olive oil is quality index as it depends on the amount of acid oleico in it. The oleico acid is acid 18 carbon atoms acid. CH3(CH2)7CH=CH(CH2)7COOH. It is a solid that melts at 16°. At room temperature it looks like a liquid of variable aspect ranging from colourless to yellowish with a distinctive odour.

Like triglyceride it is an important member of animal fats and is the most abundant constituent of most of the vegetables oils. Oleico acid represents 75% of olive oil acids. The percentage of free oleico acid present in the olive oil determines his acidity and, as a consequence of it, his denomination.

So the olive oil can be considered extravergine (very pure) if it is allowed a percentage of no more than 0,8% of free oleico acid in all the weight.

The food use of the olive oil, of course, it is stronger in production areas where it contributes in very substantial way to characterize what is called Mediterranean diet.

Among people who make exclusive use of olive oil in fact it becomes less frequent the incidence of strokes and cardiovascular disease although the caloric contribution of the feed is high.

Numerous studies have shown that the olive oil reduces LDL (Low Density Lipoproteine)factors and VLDL (Very Low Density Lipoproteine), they provoke dramatically bad cholesterol deposits on the walls of the arteries threatening their integrity and potentiates instead factor HDL good cholesterol, that keeps away the cholesterol from the walls of the arteries and takes it back to the liver where it contributes to the formation of the bile whose function in the digestion is to emulsify with fat.

It is possible thanks to the composition of the olive oil and especially to % oleico unsaturated acid that makes it the most recommendable of dressings. As well as to be a good protector of the arteries, the olive a takes also great importance in deterrence of cancer: it is strongly recommends in frying foods because his point of smoke is 140 – 180° and can reach the 280° without burning thanks to his low acidity. It is possible thanks to the composition of the olive oil and especially to % oleico unsaturated acid that makes it the most recommendable of dressings. As well as to be a good protector of the arteries, the olive a takes also great importance in deterrence of cancer: it is strongly recommends in frying foods because his point of smoke is 140 – 180° and can reach the 280° without burning thanks to his low acidity.

Nothing else can get fat undamaged temperatures from so high as it requires the frying. The olive oil is formed in its totality of almost glicerides that is glycerin linked by fat to long- chain fat acid. However as a result of partly natural processes due to fermentation induced on too much ripe olives, not too healthy, piked with systems that damage them and worked in crude way, with insufficient attention to cleaning the glyceride splinters off and fat acid is free. The percentage of these free acids determines the acidity. It is obvious that with the rising of the acidity level of the quality of the oil is modified and the commercial value is reduced.

The acidity as quality indicator

The acidity is direct consequence of the release of fat acids and is a qualitative parameter that can definable only by means of lab analysis. It is the parameter that allows to assess the alteration that the olive oil got from them undergo during the harvest, the transport and the process of transformation. Besides this, his commerce assessmen enables the oils classification. So it can be concluded that the degree of acidity of an oil is highly conditioned by the health state of olives from the picking technology, the time for storage, the technology adopted transformation tecnology, the cure of the workers in the treatment and storage of the product.

Based on the quality of the olive, of their freshness and integrity, of the degree of acidity of the work, the olive oils can be classified like this: Extra virgin (pure) olive oil Oil olive of advanced category of olives obtained from olives and only by means of mechanical procedures. Olive oil virgin whose free acidity, expressed in oleico acid, is a maximum of 0,8 g for 100 g.

Virgin (pure) olive oil Olive oil obtained right from the olive and only by means of mechanical procedures. Olive oil virgin whose free acidity, expressed in oleico acid, is a maximum of 2 g for 100 g. Olive oil composed of oils refined olive and virgin olive oil. Exclusively containing olive oil that have a refining process and oils obtained right from the olives. Olive oil obtained from the suitable refined olive oil with virgin oil different from “bright” oil, with an amount of free acidity, expressed in oleico, not advanced acid 1 g for 100 g. Olive oil husks Exclusively containing oils derived from the working of the product obtained after the extraction of the olive oil and oils obtained right from the olives. Or exclusively containing oil coming oils from the treatment of the husks of olive and oils obtained right from the olives. This oil is got from suitable husks refined oil and virgin olive oil different form “bright” oil with an amount of free acidity expressed in no advanced oleico acid 1 g for 100 g.

Thank you for your attention! Istituto comprensivo Milena-Campofranco Italia