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This study aimed to investigate the quality parameters and the oxidative stability (180 days of storage) of a water-oil emulsion formulated with Calabrian (Italy) monovarietal Agristigna extra virgin olive oil and apple vinegar. The best extra virgin olive oil/apple vinegar ratio was found to be 85/15 ( v / v ) and lecithin (2% w / v ) was the best additive to reach proper stability and viscosity over time. An increase of lightness parameters was evidenced in both products in a storage time-dependent manner. During storage, both oil and dressing showed a free acidity level beyond the accepted limit for extra virgin olive oil, whereas a slight increase of the peroxide value was observed only for Glasoil at the end of the observation time without affecting sensory attributes. A general decrease of phytochemicals was observed for extra virgin olive oil and Glasoil, with different reduction trends and degrees depending on the chemical class. A lower stability of Glasoil during shelf-life was confirmed by the worsening of the rheological features and by the polyunsaturated fatty acids reduction (up to -21.71%) with a corresponding increase of the monounsaturated fatty acids/polyunsaturated fatty acids ratio (about +25.69%).

Since ancient times, vegetables have been preserved in oil, to be consumed throughout the year, and not just during the period in which they were harvested. Dried tomato slices in Extra Virgin Olive Oil (EVOO) are one of the most famous Italian preserves. This is the first study which aimed to investigate the shelf-life parameters of this preserve during the 12 months of storage in both light and dark conditions. For this purpose, quality and CIELab color parameters were analysed in EVOO alone and as preserving liquid; total phenols and carotenoids content as well as β-carotene and lycopene content, a fatty acids profile, and antioxidant activities were examined. Results showed that samples stored in the dark are protected against degradative processes. Moreover, after 6 months of storage, the EVOO used as preserving liquid is enriched by the phytochemicals contained in dried tomato slices. This enrichment of EVOO by tomato bioactive compounds is reflected in the increase in the antioxidant activity of the oil independently by the presence of light during storage.

A comprehensive data collection of authentic "specialty" or "gourmet" oils, namely cold-pressed industrial virgin oils, was performed. Eight different botanical species, i.e., Almond, Apricot, Avocado, Hazelnut, Mosqueta rose, Rosehip, Sunflower, and Walnut oils were studied plus Olive oil as the gold standard of cold-pressed virgin oils. Two different analytical approaches are proposed to rapidly verify the botanical species of the oil-based raw material. The first approach is based on a multivariate statistical analysis of conventional analytical data, namely their fatty acid composition. These data have been re-elaborated in a multivariate way by Principal Component Analysis (PCA) and classification methods. The second approach proposes a fast and non-destructive spectrophotometric analysis to determine the color of these oils to discriminate among different species. In this regard, the raw diffuse reflectance spectra (380-780 nm) obtained by a UV-Vis spectrophotometer with an integrating sphere was considered and elaborated by chemometrics. This information was compared with the results obtained by the most common approach based on the CIELab parameters. A data fusion of chromatographic and spectral data was also investigated. Either fatty acid composition or color of these oils demonstrated to be two promising markers of their botanical authenticity.