PROCESS CONDITION OPTIMIZATION FOR SOLVENT EXTRACTION OF COCOA POD BY POLYPHENOLS ANTIOXIDANT LEVEL AND ACTIVITIES
Authors: Azila A. K. and Nur Azilah A.
Journal Issue: Malaysian Cocoa Journal, Volume 13(2)/2021
Keywords: Optimization, cocoa pod, solvent extraction, polyphenols
Published On: 1/11/2021
Abstract
This study was carried out to obtain the optimum condition of solvent extraction of cocoa pod extract using aqueous ethanol by measuring its polyphenols antioxidant levels and activities. Parameters of interest are solvent percentage (75-95%), time of extraction (15-45 min) and temperature of extraction solvent (30-40oC). The extraction was carried out using a water bath shaker at 120 rpm. The dependent variables are total phenolic content (TPC; mg GAE/g), total flavonoids content (TFC; mg RE/g), DPPH scavenging effect (DPPH %), effective concentration of DPPH (EC50D), FRAP value (μmol Fe2+/L), effective concentration of FRAP (EC50F), β-carotene bleaching (BC %) and effective concentration of β-carotene bleaching assay (EC50B). The results showed that varying the condition of extraction influence significantly, only onto two dependent variables, namely TPC and EC50D. Interaction between solvent percentage and temperature significantly affected EC50D, at p-value 0.003, while solvent percentage and time affected TPC (p=0.002). Optimum extraction condition was achieved at solvent percentage 80.94%, extraction time 17.48 minutes and 35.29oC resulting TPC value of 153.30 mg GAE/g and EC50D at 0.086, which was validated. In addition, significant strong positive correlation was observed between TPC and TFC (r=0.985), as well as EC50D versus TPC (r=0.670) and TFC (r=0.785). These results showed scavenging activity was contributed by the TPC and TFC, while ion reducer and inhibition of lipid peroxidation was contributed by probably other groups of bioactive compounds in cocoa pod extract. The model can be used to extract the polyphenols antioxidant compounds from cocoa pods at optimal operating condition.