J. of Supercritical Fluids 50 (2009) 91–96 Contents lists available at ScienceDirect The Journal of Supercritical Fluids journal homepage: www.elsevier.com/locate/supflu Phase equilibria for the removal of ethanol from alcoholic beverages using supercritical carbon dioxide Tiziana Fornari a,∗ , Elvis Judith Hernández a , Alejandro Ruiz-Rodriguez b , F. Javier Se˜ norans a , Guillermo Reglero a a Sección Departamental de Ciencias de la Alimentación, Universidad Autónoma de Madrid, Campus de Cantoblanco, E-28049 Madrid, Spain b Instituto de Fermentaciones Industriales, CSIC, Juan de la Cierva, E-28006 Madrid, Spain article info Article history: Received 15 January 2009 Accepted 31 May 2009 Keywords: Carbon dioxide Phase equilibria Supercritical fluid Dealcoholization abstract The removal of ethanol from alcoholic beverages using supercritical carbon dioxide (CO 2 ) as solvent was studied considering the CO 2 + ethanol + water mixture as model system. The extensive phase equilibria data reported in the literature for this ternary system, together with new experimental data of different CO 2 +alcoholic beverage mixtures, were employed to analyze the effect of temperature and pressure on the phase behavior of the supercritical dealcoholization process. It was demonstrated that phase envelopes and tie-lines of the ternary CO 2 + ethanol + water phase diagram depend on CO 2 density. Thus, different combinations of extraction temperature and pressure can produce the same removal of ethanol from the alcoholic beverage. The GC-EoS thermodynamic model was used to represent phase equilibria behavior and to simulate a countercurrent multistage dealcoholization process. Despite extraction temperature and pressure, at constant CO 2 density almost the same elimination of ethanol was attained and the concentration of ethanol in the dealcoholized product was mainly determined by the ratio between the solvent to beverage flows. © 2009 Elsevier B.V. All rights reserved. 1. Introduction Several drinks with low ethanol content or without ethanol have been introduced on the market in recent years. The increasing pub- lic consciousness about the abuse of alcohol has led more people to consume non-alcoholic drinks. These drinks have gained significant sales percentages in the beverage industry. Different processes can be employed to reduce the ethanol content in alcoholic drinks. In general, better taste is obtained when ethanol is removed from the beverage after fermentation than when restricted fermentation methods are employed [1]. Vac- uum distillation, membrane techniques and CO 2 supercritical fluid extraction (CO 2 -SFE) can be used in the dealcoholization process. All these techniques have the disadvantage of eliminating the bev- erage aromas together with ethanol, but still, among them, CO 2 -SFE is particularly attractive because water, salts, proteins and carbohy- drates are not substantially removed or denatured [1]. The removal of ethanol from alcoholic beverages implies a prob- lem of ethanol separation from aqueous solutions, since most alcoholic beverages contain large amounts of water. This problem ∗ Corresponding author. Tel.: +34 914972380; fax: +34 914978255. E-mail address: tiziana.fornari@uam.es (T. Fornari). was studied by different research groups [2–6] and phase equi- libria data of the ternary CO 2 + ethanol + water mixture have been reported at different temperature and pressure conditions [7–11]. CO 2 -SFE of alcoholic beverages in countercurrent pilot-scale packed column has been reported by several authors. Medina and Martínez [1] have studied the dealcoholization of cider; Gamse et al. [12] presented a CO 2 -SFE process for the utilization of excess wine of poor quality; and Se ˜ noráns et al. [13] proposed CO 2 -SFE with an on-line fractionation of the extract in two separator cells, to concen- trate the aromatic components of brandy flavor. Additionally, some patents are accessible for producing alcohol-free wine [14,15] using CO 2 . Besides the limitations concerned with mass transfer, the maximum theoretical separation that can be produced in a coun- tercurrent extraction column is governed by thermodynamic phase equilibria. In this work, the removal of ethanol from alcoholic beverages using CO 2 in a variable volume equilibrium cell was measured and compared with the phase equilibria data reported in the literature [7–11] for the CO 2 + ethanol + water ternary mix- ture. Commercial alcoholic beverages of different ethanol content were employed, together with ethanol–water mixtures prepared with a specific composition. Selected combinations of temperature and pressure were established in order to demonstrate that phase envelopes of the CO 2 + alcoholic beverages phase equilibria depend 0896-8446/$ – see front matter © 2009 Elsevier B.V. All rights reserved. doi:10.1016/j.supflu.2009.05.012