Evaluation of the Antioxidant Properties of Table Olive from “Piantone Di Mogliano” Cultivar

Objectives: “Piantone di Mogliano” is an olive cultivar from Marche region, mainly located in Mogliano (Macerata). Olive drupe, in general, is characterized by the presence of important metabolites which can influence the quality and aroma of the fruit. The fruit quality is influenced also by the environment in which the olive tree is located since it may influence the expression of some enzymes involved in several metabolic processes and in the development of phenolic and aromatic compounds [1]. In addition, the table olives quality and taste are influenced by the processing methods used to debittered the raw olives that could give rise to a final product not completely satisfactory from a nutritional point of view. The aim of the present work was the production of table olives from “Piantone di Mogliano” through innovative techniques able to enhance both taste and nutritional properties of the olives. For this purpose, two techniques were used: the Sevillian style and the Natural style. On each final product, the total polyphenol content and the antioxidant activity was determined and the obtained values were compared to that of the Raw Olives (RO). Methods: The olives were subjected to Sevillian style (based on NaOH and partial fermentation) and Natural style (based only on fermentation) processes, modified in order to obtain a final product with enhanced organoleptic characteristics. On the samples RO, Sevillian and Natural Style Olives (SSO and NSO respectively) the polyphenol total content was determined according to the Folin- Ciocalteu method, the total antioxidant activity by the method of Pellegrini and coworkers [2], and the chemiluminescence assay by Gabbianelli and coworkers [3]. Results: The Polyphenol content of RO, SSO and NSO samples, revealed that RO has the highest polyphenol content (6.45 mgGAE/g), NSO keeps its phenolic composition almost unaltered (5.69 mgGAE/g), whereas the SSO have the lowest content (2.93 mgGAE/g). Chemiluminescence assay was performed using two specific probes, lucigenin and luminol, that are sensitive to superoxide anion and hydrogen peroxide, respectively. In all cases, the results indicated that the natural style olive extracts have an antioxidant activity similar to that of fresh olive extracts. As regard to the total antioxidant activity evaluation, NSO has an antioxidant activity similar to RO and proved to possess a greater antioxidant activity of SSO. Conclusions: The results of this preliminary study proved that the Natural style olives possess enhanced organoleptic characteristics and maintains its antioxidant power and total polyphenol content with respect to the table olives produced according to the Sevillian style.