Production of alcohol-free wine and grape spirit by pervaporation membrane technology

This study reports on production of alcohol-free wine and grape spirit from red wine using pilot-scale pervaporation membrane equipment. The ethanol and aroma substances were concentrated from the wine via an organophilic pervaporation membrane, which were further processed by the membrane to obtain an ethanol content above 50 vol.%. The separation performance for ethanol/water and red wine was compared to show that fouling existed when processing the red wine, and the 1st-stage permeate was found to be an excellent cleaning agent that can recover 99.15% of the initial flux. The results of aroma analysis showed that 65−70 wt% of the aroma substances existed in the permeate of pervaporation, which exhibited better smell and taste than traditional distilled liquor. The membrane performance was stable for the separation of red wine during 180 days of continuous operation. Though the investment and operating cost of pilot-scale equipment are relatively high, remuneration can be greatly improved by the utilization of alcohol-free wine and grape spirit.