Modeling and Optimization of Extraction and Energy Consumption during Ultrasound‐Assisted Extraction of Antioxidant Polyphenols from Pomegranate Peels

Abstract

Ultrasound‐assisted extraction (UAE) of antioxidant polyphenols from pomegranate peels (juice production by‐products) was studied in an agitated extractor with ultrasound generator and temperature regulation. A mathematical model for multi‐criteria optimization of UAE was proposed. This kinetic model permits the following and the prediction of polyphenols extraction yield, antioxidant activity of obtained extracts and energy consumption during extraction process in wide ranges of temperature (20–60 °C), ethanol content in the solvent (0–100% EtOH) and ultrasound power density (0–100 W/L). This model allows to visualize and understand the impacts of operating parameters on all three optimization criteria, as well as to find the operating conditions to attain a target extraction yield or antioxidant activity of the extract at minimum time or at minimum energy consumption. The advantage of ultrasound assistance was clearly demonstrated for the reduction of both extraction duration and energy consumption. The obtained high polyphenols yields and high antioxidant activity of the extracts confirmed the suitability of UAE for preparation of antioxidant‐rich plant extracts at reduced time and energy from food industry by‐products. © 2019 American Institute of Chemical Engineers Environ Prog, 38:e13146, 2019