Effects of olive wastewater and pomace extracts, lecithin, and ascorbyl palmitate on the oxidative stability of refined sunflower oil

• Published in: Journal of food processing and preservation 2018-09, Vol.42 (9), p.e13705-n/a
• Main Authors: Günal, Deniz, Turan, Semra
• Format: Article
• Language: English
• ISSN: 0145-8892; 1745-4549
• DOI: 10.1111/jfpp.13705

In this study, the effects of olive mill wastewater (OMW) and olive pomace (OP) extracts (1 and 2 mg/g), lecithin (L, 1–5 mg/g), and ascorbyl palmitate (AP, 0.2 mg/g) on the oxidative stability of refined sunflower oil (SFO) and its purified triacylglycerols (TAGs) were investigated under accelerated oxidation conditions. Induction period of TAGs increased from 6.84 to 11.27 hr, with OMW methanol extract (1 mg/g), while OP extracts provided less protection (9.79 hr) at 90°C in Rancimat. The K232 values of the SFO with extracts (1 mg/g) and AP (0.2 mg/g) was lower than those of butylated hydroxytoluene (BHT), butylated hydroxyanisole (BHA), and α‐tocopherol containing oil samples at 60°C. Binary combinations of extracts with AP (0.2 mg/g) or L (5 mg/g) also effectively decreased the K232 and K270 values of TAGs during oxidation. In conclusion, OMW and OP extracts can be synergistically used with L or AP for stabilization of SFO against oxidation. Practical applications Generally, edible oils contain high amount of unsaturated fatty acids which are susceptible to oxidation during heat required food processes. Natural antioxidants are preferably used for increasing oxidative stability of edible oils. Olive mill byproducts contain valuable phenolic compounds that have high antioxidant capacity. In this study, we studied antioxidant efficiencies of the olive wastewater and pomace extracts in sunflower oil in combinations with lecithin and ascorbyl palmitate. These combinations can be successfully used to increase the oxidative stability of sunflower oil.