Membrane-based technologies assisting wine processing industry: by-product valorization and wine dealcoholization

Nowadays, membrane-based technologies are increasingly considered for multiple applications in wine processing industry, as they offer highly efficient, scalable, and sustainable solutions to address both critical areas. In addition, they provide new opportunities for developing innovative functional products, in line with circular economy and process intensification strategies. The combination of hydroalcoholic extraction and membrane-based operations has been investigated for the recovery and purification of wine- erived bioactive compounds from white wine lees, as a potential alternative for winery wastewater treatment and valorization. Specifically, the performance of nanofiltration membranes has been assessed in terms of productivity, fouling index, and rejection of target molecules (i.e., low - molecular - weight polyphenols). The impact of membrane-based operations — including nanofiltration, reverse osmosis, and osmotic distillation — on ethanol rejection rates and the retention of main wine components has also been evaluated through experimental activities aimed at the production of partially or fully dealcoholized wines. The experimental findings expand knowledge of how to mitigate the environmental impact of winery waste and highlight the critical changes induced by dealcoholization in wine quality.