EXTRACTION OF PHENOLIC COMPOUNDS FROM TROPICAL AND ANDEAN FRUIT PEELS USING HIGH INTENSITY ULTRASOUND TECHNOLOGY WITH SCALABLE PROCESS PARAMETERS

High-Intensity Ultrasound (HIUS) is used a efficient and sustainable method for the extraction of diverse compounds with significant added value from food matrix residues, including phenolic compounds (PC). However, the assisted-HIUS extraction has primarily focused on optimizing extraction yields without considering scalability. In the presente study, PC were extracted from camu camu (Myrciaria dubia McVaugh), starfruit (Averrhoa carambola), and elderberry (Sambucus nigra L.), which were purchased in the local market. The fruit peels were manually separated, lyophilized and then ground using a laboratory mill (IKA, Germany). The particle size distribution of the ground peels was evaluated using a Particle Insight equipment (Micromeritics, USA). The assisted-HIUS PC extractions were conducted at 15 °C with 20 mL of an ethanolic aqueous solution (30% v/v) in a UP400St system (24 kHz) with a sonotrode S24d7 (Hielscher Ultrasonics, Germany). The specific energy (EE) values used were 25, 50, 75, 100, and 125 J/mL, and the amplitudes (A) 49 and 63 µm, which were chosen considering the scale-up of the process. All parameters of the PC extraction were monitored in real time. The phenolic content was measured using a rapid and high-throughput Folin-Ciocalteu assay. The equivalent diameters of camu camu (Cc), starfruit (Sf), and elderberry (Eb) peel powder were 30-80 μm, respectively. The optimal extraction conditions for the phenolic compounds from Cc, Sf and Eb were EE = 25 J/mL and A = 49 μm. The scalability of the assisted-HIUS PC extractions were validated using 250 mL of solvent with a sonotrode S24d14D (Hielscher Ultrasonics, Germany)