Acidity levels in good olive oils:
A couple of days ago I wrote an article about the benefits of oleic acid, a fatty acid present in the triglycerides of olive oil. Today I am going to explain the different grades of acidity in olive oils, what that grade of acidity means and which levels correspond to best oils.
With this aim, it is important to analyze the features and qualities of the most important fatty acids that form the triglycerides of olive oil: oleic, linoleic and linolenic acids. The oleic acid is a fatty acid present in a very high proportion in olive oils; nearly the 75% of its composition. Decreasingly, in a second place, the linoleic acid is in between 3.5%-21%. As in the case of the oleic acid, our body is not able to synthesize it; therefore, its consumption is necessary and beneficial.
Another present fatty acid in oil is the linolenic acid, a polyunsaturated fatty between 0 and 1.5%. The main difference between this acid and the linoleic one is that the first is omega-6 and the second omega-3. The linolenic acid is beneficial to our health; nevertheless, it has been impossible to determine its behavior. It is only known that it helps to decrease possible arrhythmias and to protect neuron functions avoiding ischaemias and epilepsies.
It is obvious that if the benefits of these three fatty acids are added up to, the diary consumption of olive oil becomes essential. All together they constitute more than the 85% of olive oil, though exact proportions would vary according to the following: kind of land, resultant fruit, maturity, climatology, altitude, etc. These variations will determine oil quality. The more proportion of fatty acids in your oil, the better.
Acidity levels in good olive oils is something quite different that has not to be confused with the proportion of fatty acids in oil. Acidity comes from a chemical breakdown of triglycerides that is produced by a process known as hydrolysis or lipolysis. This breakdown leaves free fatty acids that determine acidity level. When the oil is extracted carelessly from poor quality olives and the meteorology has not been good, acidity levels will be higher because these anomalies favored the breakdown process. Thus, the percentage of free fatty acids will be very high, the acidity too and the quality of olive, poor.
The grade of acidity reflects the quality of the olive oil and also the conditions during the sowing season, the harvesting and the extraction of olive juice. An olive oil extracted from a healthy and fresh fruit that has been obtained through non aggressive methods, will suffer a minimum breakdown process and the presence of free fatty acids will be very low. Therefore, the acidity level will be under 0.8.
Extra virgin olive oils, the highest quality oils, will have an acidity lower than 0.8; virgin olive oils will have a level lower than 2% and the rest of oils that have to be refined will be between 10 and 20%.