Effect of storage management on free fatty acid content in dry cocoa beans

Abstract

Though not a quality parameter, it is expected that the free fatty acids (FFA) content must be less than 1.0% to meet the acceptable level of 1.75% in cocoa butter extracted from the dry cocoa beans. This study therefore investigates the FFA content of stored dry cocoa beans from Ghana that was generally low compared to that of Côte d’Ivoire. The FFA content of dry cocoa beans increases with storage time and this was evident for both countries. The mean FFA of Ghana’s cocoa beans was 2.03% in 1999 and 0.90% in 2008 while that of Cote d’Ivoire’s cocoa beans was 2.57% in 2002 and 1.43% in 2008. The low mean moisture content of 6.5% of Ghana cocoa beans and the mean moisture content 8.0% of Côte d’Ivoire cocoa beans might have influenced the differences in mean FFA levels. To evaluate the effect of insect infestation on increase of FFA, dry cocoa beans were infested with ten young adults of Lasioderma serricorne (Fabricus), Tribolium castaneum (Herbst), Cryptolestes ferrugineus (Stephens) and stored for 9 mo under dry condition at 30±2°C. The mean FFA of the insect-infested dry cocoa beans increased from 0.76% at the time of storage to 1.81% after 9 mo of storage. However, the mean FFA of the control dry cocoa beans increased from 0.79% at the time of storage to 0.93% after 9 mo of storage. It could therefore be inferred conclusively that FFA content in dry cocoa beans increases with insect infestation.

Keywords: Cocoa beans, Free fatty acids, Storage management, Quality preservation, Insect infestation.