Vegetable oils are prone to oxidative processes which lead to quality and nutritional losses, particularly
under microwave heating, increasingly used in culinary procedures. Natural antioxidants can be regarded
as good strategies in the inhibition of oxidation during culinary processing. In this work the addition of
white tea and olive leaves aqueous extracts to soybean oil were evaluated as possible oxidative stabilizers
during microwave heating (0–15 min; 1000 W). Microwave heating caused severe quality, nutritional and
compositional losses, mainly beyond three minutes of heating, with marked increase in peroxide value,
K232, and K270. Olive leaves extracts increased the vitamin E availability in the samples, were able to
reduce the formation of oxidation compounds, and exhibited a higher protection against polyunsaturated
fatty acids loss. White tea extracts provided higher antioxidant activity and oxidative resistance to the
soybean oils. The use of natural antioxidants could be an effective way to protect soybean oil, one of the
most important world crops, from oxidation.
