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High-resolution proton nuclear magnetic resonance (H-1-NMR) spectroscopv (400-600 MHz) was applied to the quantitative analysis of hydroperoxide decomposition products in thermally oxidized oils, Different oils (olive, sunflower and soybean) were heated in a thermostatic bath (180 degrees C for 360 min). Proton NMR quantitative aldehyde analysis (n-alkanals, trans-2-alkenals, 4-hydroxy-trans-2-alkenals, alka-2,4-dienals) of fifteen oil samples (0, 60, 120, 240 and 360 minute heating) was compared with that of total polar compounds through silica column chromatography and of short-chain fatty acids. A good linear relationship (R-2 = 0.94) was found between the unsaturated aldehyde level and the amount of methyl-octanoate as well as between total aldehyde determined by H-1-NMR and total polar compounds (R-2 = 0.92). The same NMR sensitivity obtained at 400 MHz through 3000 scans was reached with only 64 scans for a total acquisition time of 2 min at 600 MHz. The potential use of H-1-NMR as a direct tool to monitor the quality and oxidative degradation in heated and fried oils is discussed.

This research aimed to characterise an innovative ‘gelato’ (Italian-style artisanal ice cream) made by adding extra virgin olive oil (EVOO) as a functional ingredient, in order to provide health benefits and a characteristic flavour. We report the chemical-physical and sensory profile of an artisanal ‘gelato’ made by adding EVOO (10% w/w) characterised by medium biophenol content (228 mg kg−1) and a green-herbaceous flavour with a moderately bitter taste. The total phenolic content of the functional EVOO ice-cream was 25 ± 0.94 mg kg−1. The additional presence of EVOO added some key volatile compounds, including trans-2-hexenal, 1-hexanol, cis-3-hexen-1-ol and trans-2-hexen-1-ol. Sensory analysis indicated the presence of a slight pungent flavour and “freshly cut grass” aroma, with a slight bitter note given by the EVOO in the ice cream. These findings could lead to the formulation of ice creams in which EVOO is used to partially replace milk fat, with improvement of the nutritional profile, and designing new foods with innovative flavours.