Effect of the temperature on the kinetics of cocoa bean shell fat extraction using pressurized ethanol and evaluation of the lipid fraction and defatted meal

Abstract

Cocoa byproducts are important inputs to the food industry. In recent decades, the consumption of these products has been reported to increase while the production of cocoa beans has reportedly decreased. In this scenario, the use of the cocoa bean shell (CS) as an alternative source of cocoa fat is a good strategy to increase the fat supply for use in food products. The main aim of this study was to characterize CS; extract fat from CS using pressurized ethanol as the solvent; perform kinetics extraction trials at temperatures of 60, 75 and 90 °C; and evaluate the lipid fraction and defatted meal characteristics. Pressurized liquid extraction (PLE) was found to be a very efficient way to obtain fat from cocoa shells, achieving high extraction yield values (up to 90%) after a single stage of contact. An increase in temperature positively influenced the composition of fat in terms of the tocopherol content, but negatively influenced the protein solubility in the defatted meal obtained at 90 °C. The experimental kinetic data of CS fat extraction were successfully mathematically described (absolute relative deviation up to 0.85%), allowing calculation of a diffusion coefficient with values between 4.56 and 12.15 × 10−12 m2 s−1, which increased with increasing extraction temperature.