Optimization of countercurrent supercritical fluid extraction conditions for spirits fractionation

Optimization of the countercurrent supercritical fluid extraction (CC-SFE) conditions to obtain distilled alcoholic drinks extracts with low alcoholic content is presented. The optimization procedure is based on the use of an experimental design and the subsequent statistical study of the data obtained. Experiments have been performed with brandy, using a countercurrent supercritical fluid extraction (CC-SFE) system on a pilot-plant scale. The beverage is brought directly into contact with the carbon dioxide current in a packed column, and the extracts are recovered in two different fractionation cells, where depressurization occurs. The main variables that influence countercurrent extraction efficiency have been studied, such as sample flow rate, solvent flow rate (that is solvent-to-feed ratio) and level of sample introduction into the extraction column. Statistical data analysis indicates the variables that clearly influence the process and also the most convenient parameter values from which to obtain a high-value concentrated extract with a rich brandy aroma and low ethanol content.