Improvement of Commercial Olive Oil Quality through an Evaluation of the Polyphenol Content of the Oily Fraction of the Olive Fruit during its Period of Maturation

摘要

The quality of commercial olive oil can be improved by selecting the olives during the period of harvesting when fruits are characterized by an optimal degree of maturation. In this research, a Mild Sample Handling (MSH) method (able to minimize the enzymatic degradation of the polyphenol during the sample preparation) was applied in order to study the dynamics of the polyphenol content of the oily fraction of the fruits during their maturation and the results were compared with those obtained through an Ordinary Laboratory Method (OLM). In the oily fraction of the olives during their maturation, a different dynamics and a higher concentration of total polyphenols was found when the MSH method was applied. This method, in comparison with the OLM, respects to a greater extent the phenolic composition of the original oily fraction of the fruits. This feature makes the MSH method suitable for monitoring the dynamics of the total phenolic compound content in the oily fraction of the fruits during their maturation in order to establish the optimal technological harvesting period. When the olives were harvested and processed at the beginning of the total polyphenol decay period in the oily fraction of the fruits extracted using the MSH method, it was possible to improve the phenolic concentration and the sensory quality of the commercial olive oil produced in the mill.