L. Gennaro et al., EFFECT OF BIOPHENOLS ON OLIVE OIL STABILITY EVALUATED BY THERMOGRAVIMETRIC ANALYSIS, Journal of agricultural and food chemistry, 46(11), 1998, pp. 4465-4469
Virgin olive oil stability to autoxidation is mainly due to phenolic c
ompounds naturally occurring in it, but contrasting data have been pub
lished on the effectiveness of the same antioxidant compounds. With th
ermogravimetric analysis (TGA) it is possible to have an estimation of
oil resistance to oxidation, having a measure of weight gain percent
due to reaction of sample with oxygen during the oxidation, and of ini
tial and final oxidation temperatures. The following samples were exam
ined: virgin olive oil, olive oil, and olive oil spiked with different
amounts of some antioxidants. Tested phenols were p-HPEA, 3,4-DHPEA,
3,4-DHPEA-EA, caffeic acid, oleuropein, and, moreover, BHT and BHA. Da
ta showed that natural antioxidant addition (especially oleuropein, 3,
4-DHPEA, and 3,4-DHPEA-EA) could extend the olive oil shelf life and c
ould protect oil from decomposition naturally occurring during thermal
treatments (such as cooking process).