Intensified synthesis of olive oil-based structured lipids based on enzymatic acidolysis using multi-frequency ultrasound

Abstract

Intensified synthesis of structured lipids based on olive oil and capric acid through enzymatic acidolysis was investigated utilizing a multifrequency hexagonal ultrasonic reactor. The ultrasound-assisted process achieved a 59 % conversion of olive oil into structured lipids in just 4 h, compared to a 52 % conversion in 6 h with the conventional approach. The optimized parameters for the ultrasound-assisted process were a 4:1 M ratio, 4 % enzyme loading, 60 °C temperature, 30 W ultrasonic power, a 60 % duty cycle, and a combined frequency as 22 + 33 kHz. Sn-2 positional analysis confirmed the enzyme’s specificity for the glycerol 1,3 positions in the acidolysis reaction. Only 20 % loss in enzyme activity was observed after the sixth cycle, indicating the enzyme’s reusability within the process. Overall, the study effectively highlights the use of ultrasound as a powerful approach to intensify the enzymatic synthesis of designer lipids, while also elucidating the optimal operating conditions