Optimization of the extraction process of phenolic compounds from eggplant peel

Abstract

In this study, the extraction process of phenolic compounds from eggplant peels, an important industrial waste, with the help of ultrasound was optimized by Taguchi method. Experiments were carried out according to Taguchi L₉ (3³) experimental matrix. Ethanol ratio (50, 70, 90% (v/v)), sonication time (15, 30, 45 min) and sonication temperature (30, 40, 60 °C) were selected as independent variables. In this study, which aimed to maximize the total phenolic matter (TPM) content of the extracts, the optimum conditions were determined as 70% ethanol ratio, 45 min sonication time and 60 °C sonication temperature. ANOVA results showed that ethanol ratio (83.06%) and sonication temperature (14.38%) were the most significant parameters contributing to the process. According to the validation experiments carried out to verify the optimum conditions, 66.02% improvement was achieved in the TPM content obtained under optimum conditions compared to the initial process conditions.