Nowadays the recovery of water and bio-molecules from wine wastewaters and by-products has become a key topic in wine processing industry in agreement with industrial ecology and circular economy concepts. In this contest, research efforts are increasingly oriented to redesign the traditional industrial cycle closer to the concept of biorefinery, where losses are minimized and resources are used to the full, providing achievements in economic, environmental and social issues. The main objective of this work was to investigate the recovery of wine-derived bioactive compounds from white wine lees through a combination of hydroalcoholic extraction and membrane-based operations, as a potential alternative for winery wastewater treatment and valorisation. Preliminary experiments were performed in order to identify the optimal conditions (solid-liquid ratio, extraction time and working temperature) for the extraction with ethanol-water mixtures. The hydroalcoholic extract was previously microfiltered in order to produce a clarified solution free of suspended solids and colloidal substances. Then, the clarified extract was fractionated with three different spiral-wound nanofiltration membranes with a molecular weight cut-off in the range of 200-1000 Da (TS40, XN45 and NP010, all from Microdyn-Nadir). Their performance was analysed in terms of productivity, fouling index and retention towards target compounds (polyphenols, flavonoids, sugars) and antioxidant activity. Among the selected membranes the TS40, with the lowest cut-off, exhibited higher rejections for phenolic compounds allowing to obtain concentrated fractions with a total polyphenol content up to 1.7 g GAE/L and permeate streams with negligible content of phenolics.
Membrane-based fractionation of white wine lees hydroalcoholic extracts
C Conidi;A Cassano
2023
Abstract
Nowadays the recovery of water and bio-molecules from wine wastewaters and by-products has become a key topic in wine processing industry in agreement with industrial ecology and circular economy concepts. In this contest, research efforts are increasingly oriented to redesign the traditional industrial cycle closer to the concept of biorefinery, where losses are minimized and resources are used to the full, providing achievements in economic, environmental and social issues. The main objective of this work was to investigate the recovery of wine-derived bioactive compounds from white wine lees through a combination of hydroalcoholic extraction and membrane-based operations, as a potential alternative for winery wastewater treatment and valorisation. Preliminary experiments were performed in order to identify the optimal conditions (solid-liquid ratio, extraction time and working temperature) for the extraction with ethanol-water mixtures. The hydroalcoholic extract was previously microfiltered in order to produce a clarified solution free of suspended solids and colloidal substances. Then, the clarified extract was fractionated with three different spiral-wound nanofiltration membranes with a molecular weight cut-off in the range of 200-1000 Da (TS40, XN45 and NP010, all from Microdyn-Nadir). Their performance was analysed in terms of productivity, fouling index and retention towards target compounds (polyphenols, flavonoids, sugars) and antioxidant activity. Among the selected membranes the TS40, with the lowest cut-off, exhibited higher rejections for phenolic compounds allowing to obtain concentrated fractions with a total polyphenol content up to 1.7 g GAE/L and permeate streams with negligible content of phenolics.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
