Abstract

QUIROZ-REYES, C.N.; AGUILAR-MENDEZ, M.A.; RAMIREZ-ORTIZ, M.E.  and  RONQUILLO-DE JESUS, E.. Comparative study of ultrasound and maceration techniques for the extraction of polyphenols from cocoa beans (Theobroma cacao L.). Rev. Mex. Ing. Quím [online]. 2013, vol.12, n.1, pp.11-18. ISSN 1665-2738.

Polyphenols have gained significant interest in recent years due to their antioxidant capacity and their important role in disease prevention. In this work, the phenolic content and antioxidant properties of cocoa extracts prepared by maceration and ultrasound-assisted extraction were studied. The polyphenol content was determined using the Folin-Ciocalteu reagent and the antioxidant activity was estimated by DPPH (2,2-diphenyl-2-picrylhydrazyl) and FRAP (Ferric reducing/antioxidant power) assays. The identification and quantification of (+)-catechin and (-)-epicatechin were performed using high-performance liquid chromatography (HPLC). The results showed that by using ultrasonic radiation, it was possible to obtain higher polyphenol contents from both the husk and cotyledon of cocoa. Furthermore, extracts obtained by sonication showed the highest antioxidant activity, thus proving that this activity depends directly on the total phenolic content. The contents of (+)-catechin and (-)-epicatechin were higher in the cotyledon extracts compared to those of the husk.

Keywords : cocoa; polyphenols; extraction; ultrasound; antioxidant activity.