Physicochemical and Oxidative Changes in Sonicated Interesterified Soybean Oil

The effect of power ultrasound on physicochemical properties and oxidative stability of an interesterified soybean oil (IESBO) was investigated. IESBO was crystallized at 32 °C and sonicated for 10 s with acoustic power of 101 W. The sonicated IESBO was tested for melting behavior and chemical composition and compared to those of non sonicated IESBO to determine physical and chemical changes originated as a consequence of sonication. Application of power ultrasound affected the melting behavior of the crystallized fat and did not affect its chemical composition. Oxidation stability of the sonicated IESBO was measured using peroxide value (PV) and compared to that of non sonicated IESBO and liquid soybean oil (SBO) when stored at 25 °C for 105 days followed by storage at 40 °C for 42 days. Power ultrasound did not cause accelerated oxidation in SBO or IESBO until they were highly oxidized (PV > 10 mequiv/kg). At high levels of oxidation, non‐sonicated IESBO had significantly higher PV than sonicated IESBO, while non‐sonicated SBO had significantly lower PV than sonicated SBO.