Application of different thermal analysis techniques to characterize oxidized olive oils

Abstract

The deep changes caused by oxidation on virgin olive oil (VOO), which is a high-quality product, not\ud subjected to ameliorative refining, make this phenomenon one of the most studied. Among the\ud techniques used to study oxidation in olive oil, thermal analysis (TA) provides useful information about\ud the thermal behavior of the samples as affected by oxidation. Thermogravimetry (TG), measuring the\ud changes in the sample mass, can monitor the kinetics of oil mass loss in decomposition processes or\ud oxidation and has been found particularly useful, especially when operating simultaneously with\ud Differential Thermal Analysis (DTA) or Differential Scanning Calorimetry (DSC). The DSC thermal\ud curves of olive oil, both on cooling and heating, has been found to be largely influenced by the oxidative\ud status of the samples and different statistical approaches have been successfully proposed to correlate the\ud thermal parameters with the conventional chemical indicators of oxidation. DSC can be also used to\ud study the kinetics of phase transition phenomena as affected by oxidation. This review provides an\ud exhaustive survey about the application of the thermoanalytical techniques on this topic proposing them\ud as as a fast and green alternative to conventional chemical methods

Oxidation Behavior of Light Crude Oil and Its SARA Fractions Characterized by TG and DSC Techniques: Differences and Connections

“…In this study, oxidation behavior was investigated by thermogravimetry (TG) and differential scanning calorimetry (DSC). These thermal analysis techniques have obtained wide acceptance and been widely used in the characterization of the combustion or pyrolysis behavior of hydrocarbons and their derivatives. − In this study, a NETZSCH STA 449 F3 Jupiter (Netzsch, Germany) was used to characterize the oxidation behavior of the crude oil and its SARA fractions. Before experiments, temperature and sensitivity calibrations were conducted in an open alumina crucible filled by the standard samples of seven different metals indium (In), tin (Sn), bismuth (Bi), lead (Pb), zinc (Zn), aluminum (Al), and gold (Au) at the different heating rates from 2 to 20 °C/min in a dynamic air atmosphere.…”

Physical and Thermal Evaluation of Olive Oils from Minor Italian Cultivars

“…Differential scanning calorimetry (DSC) has been proposed as an alternative and reproducible method for olive oils identification, through the study of their thermal behavior upon cooling and heating [ 15 ]. This technique has been successfully applied in the field of olive oil with the aim to discriminate between commercial categories [ 16 ], oxidative status [ 17 ], agronomic practices [ 18 ], or to detect fraudulent mixtures with other vegetable oils [ 19 ]. Some studies have also applied DSC to study the authentication and traceability of extra virgin olive oils by applying chemometric data processing.…”

Oil crystallization properties as an index for monitoring early stage curing of oil-based paints: DSC analysis on linseed oil systems

“…Considering that lipolysis, autoxidation and photooxidation influence the DSC profiles [30], while the presence of pigments did not significantly affect most of the two melting profiles, we may argue that autoxidation chain reactions, that are the basis of the polymer network formation, have not occurred yet to a significant extent in the case of fresh paints. Indeed, considering the different chemistry of lead white and ultramarine blue on linseed oil curing process, we would expect differences on the kinetics of the formation of the polymer network [19] (see below for more details), and in turn differences in LWLO and UBLO overall curves.…”

“…As a matter of fact, the DSC technique has been widely used to study, among other physicochemical proprieties, the crystallization and melting profiles of oils in complex matrices in the food research [20][21][22][23][24][25][26][27][28][29][30], allowing the detection of matrix effects on the oil crystallinity degree as well as on the oil crystals stability. Nonetheless, to our knowledge, no analogous application of the DSC technique on paint systems has been reported yet in the literature, and this work represents the first attempt to exploit such an approach for the monitoring of oil-paint curing.…”