Microwave-Assisted Bleaching of Olive Pomace Oil: Optimization of Bleaching Parameters and Comparison with Conventionally Bleached Oil

In this research, microwave-assisted bleaching of olive pomace oil is studied under different conditions. Microwave power, mixing time, and adsorbent dosage are optimized using the response surface central composite design, where the optimum conditions are 102 W, 20.07 min, and 4.15%, respectively. The microwave-bleached oil is compared with the conventionally bleached oil in terms of color, oxidation parameters, sterol composition, and benzo[a]pyrene content. Microwave-assisted bleaching of the olive pomace oil is performed by using 17% less adsorbent in an 83% shorter time compared to the conventional method. A bleaching performance comparable to the conventional method is achieved using the microwave-assisted bleaching technique. Microwave-assisted bleaching can thus be used as an alternative method for the bleaching of olive pomace oil. Practical applications: The microwave-assisted bleaching method presents attractive advantages, including a shorter bleaching time and a lower amount of adsorbent used. In this respect, the current research contributes toward the conventional bleaching method in the vegetable oil refinery industry and creates a paradigm for future studies on the bleaching of vegetable oils.