Impact of carotenoids on the oxidative stability and trans fatty acid content of sunflower oil by using central composite design

The oxidative stability such as induction time (IT), conjugated diene (CD), conjugated triene (CT) and trans fatty acid (TFA) of sunflower oil added β-carotene, lutein, and lycopene was evaluated by using an experimental design technique. Oil samples with and without lutein, β-carotene, and lycopene were prepared according to central composite design (CCD). To examine the effects of β-carotene, lutein, and lycopene, CCD was applied at different five levels (− 1.68, − 1, 0, 1, 1.68). The obtained results demonstrated that carotenoid types and amounts were very effective in change IT, CD, CT, and TFA formation of sunflower oil. The increase in the lutein amounts decreased the IT and increased the CD and CT of the oil although the addition of the lutein at low concentrations showed increase in TFA formation. The results revealed that β-carotene and lycopene in oil samples were the most effective factor for the resistance to oxidation of the oil.