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2. M.T. Bilancia, F. Caponio, E. Sikorska, A. Pasqualone, T. Gomes, C. Summo (2007). Determinationof oil colour during storage: a tool for a rapid quality assessment. Shelf Life InternationalMeeting, Catania, 21-23 giugno 2006. Ital. J. Food Sci. Special Issue, 400-403.The oxidation of virgin olive oil leads to the degradation of pigments, which are responsible for oil colour, and tothe formation of new compounds absorbing in the UV-Vis spectral range and thus contributing to the colourchanges. Therefore, colour can be a critical tool for oil quality assessment and for monitoring the changes occurringduring storage. The aim of this study was to evaluate the correlations between the colour parameters, measuredas E (colour difference between fresh oil sample and the samples stored in different conditions and for acertain period of time), and some important analytical indexes measured during a storage period of 12 months indifferent conditions. The obtained results showed significant regression coefficients for the correlations betweenthe colour parameters and the concentrations of chlorophylls, carotenoids and triglyceride oligopolymers, as wellas with the K 270 values.3. M.T. Bilancia, F. Caponio, E. Sikorska, A. Pasqualone, C. Summo (2007). Correlation of triacylglycerololigopolymers and oxidised triacylglycerols to quality parameters in extra virginolive oil during storage. Food Res. Intern. 40, 855-861.The evaluation of the effect of storage on extra virgin olive oil is usually achieved basing on the concurrence ofmany analytical methods. With the aim of reducing the number of determinations to carry out, the levels of triacylglycerololigopolymers and oxidised triacylglycerols, determined by high-performance size-exclusion chromatography(HPSEC) analysis of the polar compounds of the oil, have been evaluated. The obtained results highlightedthat the oxidised triacylglycerols were significantly correlated (p < 0.001) in a positive way with peroxidevalue and K 232 and in a negative way with total phenols and induction time, hence they can give indications aboutthe primary oxidation level of the oil. The triacylglycerol oligopolymers, instead, were found to be significantlyand positively correlated (p < 0.001) with K 270 that denotes the secondary oxidation of an oil. On the contrary,significant negative correlations (p < 0.001) between triacylglycerol oligopolymers and both the contents of carotenoidsand chlorophylls, whose contents in the oil seriously diminish when the secondary oxidation is high,were found.4. E. Sikorska, F. Caponio, M.T. Bilancia, C. Summo, A. Pasqualone, I.V. Khmelinskii (2007).Changes in colour of extra-virgin olive oil during storage. 3 rd International Conference “Qualityand safety in food production chain”. Wroclaw 13-15 June 2007. Pol. J. Food Nutr. Sci.57, 495-498.The changes in colour parameters were studied for an extra-virgin olive oil stored for a period of one year indarkness and exposed to light. Colour parameters were found to correlate with the content of carotenoids andchlorophylls and may thus be used for oil quality control and fast quantitative analysis of the oil chromofores.5. E. Sikorska, I.V. Khmelinskii, M. Sikorski, F. Caponio, M.T. Bilancia, A. Pasqualone, T.Gomes (2008). Fluorescence spectroscopy in monitoring of extra virgin olive oil during storage.Int. J. Food Sci. Tech. 43, 52-61.The present study demonstrates the use of fluorescence spectroscopy for monitoring changes in virgin olive oilduring storage. Total luminescence and synchronous scanning fluorescence spectroscopy techniques were testedwith the purpose to check their ability to monitor changes occurring in olive oil during storage in different conditions:in clear and green glass bottles exposed to light, and in darkness. Total luminescence spectra of the initialoil samples in n-hexane solutions exhibited intense peaks, one with a maximum appearing at 320 nm in emissionand 290 nm in excitation, attributed to tocopherols, and another appearing at 670 nm in emission and 405 nm inexcitation, belonging to the pigments of the chlorophyll group. The intensity of these emissions decreased duringstorage depending on the storage conditions. Additional bands appeared in oils exposed to light in the intermediaterange of excitation and emission wavelengths, arising from unidentified compounds. Bands attributed to tocopherols,chlorophylls and those tentatively ascribed to phenolic compounds were observed in the synchronousscanning fluorescence spectra, allowing monitoring of the storage effects on these constituents and their quantitativeassessment after appropriate calibration. The results presented confirm the capability of the fluorescencetechniques to monitor the quality of oil products.SISTAL - SOCIETA’ ITALIANA DI SCIENZE E TECNOLOGIE ALIMENTARIDipartimento di Scienze e Tecnologie Agroalimentari, Università degli Studi della TusciaVia San Camillo de Lellis, 01100 ViterboTel.: 0761- 35 74 94/7 , Fax: 0761- 35 74 98, e-mail: mmoresi@unitus.it7