Effects of polar cosolvents on cocoa butter extraction using supercritical carbon dioxide

• Cocoa butter extraction from cocoa liquor using supercritical fluids
• Effects of polar cosolvents on cocoa butter extraction
• Cocoa butter quality based on extraction method
• Triglycerides in term of fatty acids constituents

Cocoa butter was successfully extracted from cocoa liquor by supercritical carbon dioxide (SC–CO2) at 35 MPa, 60 °C and 2 mL/min with 5%, 15% and 25% cosolvents. The extraction yield of triglycerides (TG) and fatty acid (FA) compositions were significantly influenced by the concentration of polar cosolvents. The SC–CO2 extraction efficiency was increased with cosolvent significantly. Ethanol was found to be the best cosolvent for cocoa butter extraction using SC–CO2 followed by isopropanol and acetone. The triglycerides of 1,3-dipalmitoyl-2-oleoylglycerol (POP), 1-palmitoyl-2-oleoyl-3-stearoyl-glycerol (POS) and 1,3-distearoyl-2-oleoyl-glycerol (SOS) were contained in the extracted cocoa butter with POS being the major component. Where palmitic, stearic and oleic were the main fatty acids in the cocoa butter samples, with stearic being the highest component. The lower molecular weight (MW) of TGs and FAs showed the higher selectivity compared to the high MW of TGs and FAs. Thus, they were fractionated during the first stage of SC–CO2 process.Industrial relevanceThe cocoa butter was successfully extracted from cocoa liquor by SC–CO2 at 35 MPa, 60 °C and 2 mL/min using different concentrations of polar cosolvents (ethanol, isopropanol and acetone). The extraction yield was significantly (p < 0.05) influenced by the concentration of polar cosolvents. Similarly, polar cosolvent concentration had significant (p < 0.05) effects on the TG and FA compositions. Ethanol was found to be the most efficient polar cosolvent for cocoa butter extraction compared to isopropanol and acetone. POS (42.2–45.9%) being the major triglycerdies component, followed by SOS (27.6–31.4%) and POP (20.3–22.7). Palmitic, stearic and oleic acids were the main fatty acids in the extracted cocoa butter, with stearic being the highest (34.9-37.8%), followed by oleic (30.3-31.8%) and palmitic (28.3-30.0%) acids, respectively. The choice of modifiers becomes a great challenge and ethanol was shown to be the best polar cosolvent, and it enhanced the solubility during the cocoa butter extraction by SC–CO2. This method can be feasibly implemented in the cocoa industry for the production of high quality cocoa butter.