A study on vegetable oil blends

The oil stability index (OSI) and peroxide value (PV) were used to determine the quality of oil blends. The quality of soybean oil (SBO) blended with other refined, bleached and deodorized (RBD) oils was between the quality of SBO and the RBD oils selected for blending. However, crude peanut oil blended with SBO diminished the quality of SBO while crude sesame oil with unique antioxidants improved the quality of SBO blends. To study the effect of fatty acid composition (FAC) on the oxidative stability of oil blends, 21 oil blends were prepared by using 7 commercial RBD oils which were re-deodorized and followed by tocopherol adjustment. A mathematical model describing the relationship between OSI and FAC of 21 oil blends was obtained as follows: OSI (h) = 7.5123 + % C16:0 × (0.2733) + %C18:0 × (0.0797) + %C18:1 × (0.0159) + %C18:2 × (−0.1141) + %C18:3 × (−0.3962), r2 = 0.911. The difference between the values of each predicted and measured OSI were within 10%, which indicated that the oxidative stability of oil blends of any ratio from the 7 RBD oils under study could be predicted by using this model.