The alcohol content of Tokaji Harslevelu (Linden leaves) wine samples was reduced by pervaporation process. The advantages of this modern membrane technique made us succeed in manufacturing a final product of a quality that matches the sensoric value of real wines. A wine almost free of alcohol produced by this method may be used as a substitute with no harmful effect due to its low ethanol content. The organoleptic characteristics are expected not to decrease due to of the mild process, so the positive physiological influence might be associated with the features close to the original character of the wine. Pervaporation experiments on a laboratory scale have been performed at different temperatures. The alcohol concentrate crossing the membrane, and thus separated, has been collected as a by-product and the remaining mixture of alcohol free wine compounds was considered the main product of the process. The separated wine samples and the extracted alcohol concentrates were then gas chromatographically analysed. The influence of process parameters on the result, from the aspect of optimization and planning, has been analysed, and the experiences of this analysis have been. built in empirical and quasi-empirical models. Knowing the membrane-characteristics, we were capable of defining the equations that enable the planning of the pilot-plant scale unit operations and, the estimation of costs. The results of this investigation show that working temperature plays the most important role in the production of low alcoholic and alcohol free wines by pervaporation. At higher temperatures the membrane's separation efficiency and the separation ability decrease. Thus, the permeate production gets faster, but less desired product is gained by separation. Economical analyses prognoses a great investment cost demand, that can be explained by the relatively high price of pervaporation membranes. Remuneration can seriously be promoted by the by-product utilization e.g. by the use of the separated alcohol concentrate as a raw material for wine distillates or industrial spirits. (c) 2005 Elsevier Ltd. All rights reserved.