PROCESS OPTIMIZATION OF ULTRASOUND-ASSISTED EXTRACTION OF POLYPHENOLS FROM COCOA BEAN SHELLS AND THEIR ANTIOXIDANT POTENTIAL

Food waste is a valuable source of bioactive compounds, and cocoa bean shells (Theobroma cacao L.) are rich in phenolic compounds with antioxidant potential. This study optimized ultrasound-assisted extraction of polyphenols by varying solvent type, solid-to-solvent ratio, and time, and evaluated the extracts’ antioxidant activity. The results showed that extraction conditions significantly affected both total polyphenol content (TPC) and IC₅₀ values. The highest TPC was obtained with 50% ethanol, while optimal conditions were a 1:30 ratio and 30 min extraction. Antioxidant activity improved with higher TPC, but only a weak correlation was observed (r = -0.37), indicating that activity depends not only on total phenolics but also on the extract’s chemical profile. Ultrasound-assisted extraction was confirmed as an efficient method for obtaining antioxidant-rich cocoa bean shell extracts.