DSC evaluation of extra virgin olive oil stability under accelerated oxidative test: effect of fatty acid composition and phenol contents.
Three extra virgin olive oils having different fatty acid compositions and total phenol contents were submitted to an accelerated storage test at 60°C for up to 21 weeks. Their oxidative status, evaluated by peroxide values and total phenolic content, was related to differential scanning calorimetry cooling profiles and thermal properties. Changes in crystallization profiles were consistent starting from 12 weeks for the two oil samples (B and C) that had a higher content of linoleic acid and medium/low amounts of phenols, respectively, whereas they became detectable at the end of the test for the remaining oil (sample A). Decrease of crystallization enthalpy and shift of transition towards lower temperature were also evident at 4 weeks of storage for samples B and C, whereas the same changes in the transition profile were noticeable at 12 weeks for sample A. Differential scanning calorimetry appears to be suitable for the discrimination of oxidative status of extra virgin olive oils with widely different fatty acid composition.
Dipartimento di Economia e Ingegneria Agrarie, Università di Bologna, Cesena (FC), Italy.
Lorenzo
L
Cerretani
Alessandra
A
Bendini
Massimiliano
M
Rinaldi
Maria
M
Paciulli
Stefano
S
Vecchio
Emma
E
Chiavaro
D002152:Calorimetry, Differential Scanning / Q000295:instrumentation / Q000379:methods*; D003460:Crystallization; D005227:Fatty Acids / Q000737:chemistry*; D006358:Hot Temperature; D019787:Linoleic Acid / Q000737:chemistry; D015233:Models, Statistical; D031658:Olea; D000069463:Olive Oil; D018384:Oxidative Stress; D010100:Oxygen / Q000737:chemistry; D010545:Peroxides / Q000737:chemistry; D019800:Phenol / Q000737:chemistry; D010636:Phenols / Q000737:chemistry; D010938:Plant Oils / Q000737:chemistry*; D013696:Temperature; D013816:Thermodynamics; D013997:Time Factors
D005227:Fatty Acids; D000069463:Olive Oil; D010545:Peroxides; D010636:Phenols; D010938:Plant Oils; D019800:Phenol; D019787:Linoleic Acid; D010100:Oxygen