Virgin olive oil production from de-stoned pastes: a new technology to improbe the shelf life of the product

The aim of increasing the quality standards for virgin olive oil is continuously stimulating the search for new technologies. In this sense, a new technological procedure is being developed that includes stone removal before the olive oil extraction process. Virgin olive oil contains a great number of volatile and non-volatile compounds mainly phenolic compounds responsible for its fragrant and peculiar flavour. These substances also contribute to the stability of the oil. Since the occurrence of phenols in virgin olive oil is strictly related to the activities of various endogenous enzymes of olive fruit, their concentration in the oil is strongly affected by the extraction conditions. In the olive seeds there is highly concentrated the peroxidase, an enzyme that catalyze phenol oxidation. The de-stoning process, excluding the olive seed before malaxation, partially remove the peroxidase activity in the pastes and consequently reduce the enzymatic degradation of the phenols in the oils improving their concentration and oil oxidative stability. Our results shown that the use of a de-stoner during the extraction process of olive oil increased total phenol content of the oil. A relationship between total phenol content and Induction time was found.