The present work describes sorption characteristics of volatile aroma compounds in pervaporation of the multicomponent aroma solution. A better understanding of the mass transfer mechanism is essential in that, among other it improves the process of designing new pervaporation membranes or that it lends itself to be used for scale-up studies. One of the two mass transport stages that are reported to have the predominant effect On pervaporation efficiency and selectivity is aroma compounds sorption in membrane material. The objective of this study was to examine the applicability of the Flory Huggins (F-H) theory and its three modifications in the modeling of sorption equilibria in hydrophobic pervaporation of a model multicomponent solution. The sorption experiments of isopentanol-methyl butyrate-polydimethylsiloxane were conducted in a wide range of feed concentrations and temperatures. The results of the experiments were used to ascertain parameters of models based on the original Flory-Huggins theory and on modifications proposed in the scientific literature. Three different models were used for data fitting, yielding the values of the coefficients of determination that range between 0.73 and 0.98. The influence of both, temperature and concentration on the model parameter was determined and the sorption separation factors were compared with pervaporation experimental results. (C) 2015 Elsevier Ltd. All rights reserved.