Isolation of brandy aroma by countercurrent supercritical fluid extraction

Optimization of the countercurrent supercritical fluid extraction (CC-SFE) conditions to obtain high quality brandy aroma extracts is presented. The main variables that influence CC extraction selectivity and efficiency have been studied, such as extraction pressure and temperature and sample flow rate (related to the solvent-to-feed ratio). A rotatable central composite experimental design is used to optimize the combination of these experimental. Experiments have been performed with brandy using a CC-SFE system at pilot plant scale. The beverage is put directly in contact with the carbon dioxide in a packed column and the extracts are recovered in two different fractionation cells, where depressurization occurs. For each experiment, two extracted fractions and a raffinate are obtained and its aroma characterized by gas chromatography. A statistical study of the data obtained is performed including analysis of variance (ANOVA), fitting of a regression model and response surface study. The obtained results allow to know the variables that clearly influence the process and also show the interest of CC-SFE as an useful technique to obtain high-value concentrated brandy aroma extracts. [Copyright &y& Elsevier]