New olive fruit processing approach with stone removal and dehydration: characterization of multifunctional "olive flour"

Olive oil is produced using, essentially, the same method that was implemented in ancient times, except for the industrial improvement and development. Current extraction processes require crushing of whole olives; these practices, however, might compromise the oil richness regarding phenolic compound and other molecules that have been demonstrated to be beneficial. Moreover, the traditional method for obtaining olive oil generates different by-products, such as olive pomace and waste water, which can be contaminants at different levels and are difficult to exploit in other areas. Those are the reasons why many researchers have recently focused on the search for innovative olive processing methods that enhance olive oil content of bioactive compounds and reduce the waste. In order to obtain a richer olive oil in terms of phenolic compounds and avoid the generation of residues, a deconstruction of the olive fruit has been proposed (Olmo-García & Olmo-Peinado, 2013a; Olmo-García & Olmo-Peinado, 2013b). It consists on a stoning of the olive fruits to obtain the pulp on the one hand and the stone on the other. After that step, the pulp is dehydrated and pressed to obtain an olive oil with higher phenolic content and a new product consisting on a hydrosoluble powder, containing high levels of fiber and abundance of bioactive compounds. This powder, which has been denominated as “olive flour”, fulfills the criteria to act as a potential ingredient for functional food. Thus, the present work has been conducted in the field of Food Metabolomics, with the objective of accomplishing the comprehensive qualitative and quantitative characterization of different olive flours, by applying a powerful analytical method (LC-MS) which allows the determination of phenolic compounds, triterpenic acids, some organic acids and tocopherols present in the matrix under study.