Winemaking generates huge quantities of waste streams represented by leaves, stems, pomaces (including grape skins and seeds) and lees. Conventional treatments of winery wastes are increasingly expensive, requiring significant amounts of effort, resources and energy for a safe discharge into the environment. Among wastes, grape pomaces and wine lees constitute a valuable source of phenolic compounds (flavonoids, tannins and benzoic acids derivatives) which are biomolecules of both technological and nutraceutical interest, acting as antioxidants in biological matrices through the inhibition of lipid peroxide radicals and reactive oxygen species [1]. In agreement with industrial ecology concepts, like cradle-to-cradle and circular economy, the need to recycle, reuse and recover valuable chemicals from waste and wastewaters has become a major topic in wine processing industry [2,3]. In this work, the combination of eco-friendly extraction techniques with membrane-based operations has been implemented in two different case studies in order to develop a sustainable process for the extraction and separation of phenolic compounds from wine by-products. In the first approach, a microwave/hydro-alcoholic extraction, followed by the clarification and fractionation of the hydro-alcoholic extract, was studied for the recovery of phenolic compounds from red wine lees. Specifically, commercial polymeric membranes with a molecular weight cut-off in the range 150-1,000 Da were tested to fractionate the hydro-alcoholic extract clarified by microfiltration. The second case study was focused on the recovery of phenolic compounds from red grape pomace through a combination of ultrasound-assisted enzymatic extraction and membrane fractionation with cellulose acetate laboratory-made nanofiltration membranes. In both cases the performance of selected membranes was evaluated in terms of productivity, fouling index and selectivity towards target compounds. Typical rejections of nanofiltration membranes to different compounds of the grape pomace extract are illustrated in Figure 1. The investigated processes represent an option of sustainability for the winery industries since the obtained fractions could be used as high value-added products due to their antiradical properties.
A combination of eco-friendly extraction techniques and membrane operations for the recovery of bioactive compounds from wine by-products
C Conidi;A Cassano
2020
Abstract
Winemaking generates huge quantities of waste streams represented by leaves, stems, pomaces (including grape skins and seeds) and lees. Conventional treatments of winery wastes are increasingly expensive, requiring significant amounts of effort, resources and energy for a safe discharge into the environment. Among wastes, grape pomaces and wine lees constitute a valuable source of phenolic compounds (flavonoids, tannins and benzoic acids derivatives) which are biomolecules of both technological and nutraceutical interest, acting as antioxidants in biological matrices through the inhibition of lipid peroxide radicals and reactive oxygen species [1]. In agreement with industrial ecology concepts, like cradle-to-cradle and circular economy, the need to recycle, reuse and recover valuable chemicals from waste and wastewaters has become a major topic in wine processing industry [2,3]. In this work, the combination of eco-friendly extraction techniques with membrane-based operations has been implemented in two different case studies in order to develop a sustainable process for the extraction and separation of phenolic compounds from wine by-products. In the first approach, a microwave/hydro-alcoholic extraction, followed by the clarification and fractionation of the hydro-alcoholic extract, was studied for the recovery of phenolic compounds from red wine lees. Specifically, commercial polymeric membranes with a molecular weight cut-off in the range 150-1,000 Da were tested to fractionate the hydro-alcoholic extract clarified by microfiltration. The second case study was focused on the recovery of phenolic compounds from red grape pomace through a combination of ultrasound-assisted enzymatic extraction and membrane fractionation with cellulose acetate laboratory-made nanofiltration membranes. In both cases the performance of selected membranes was evaluated in terms of productivity, fouling index and selectivity towards target compounds. Typical rejections of nanofiltration membranes to different compounds of the grape pomace extract are illustrated in Figure 1. The investigated processes represent an option of sustainability for the winery industries since the obtained fractions could be used as high value-added products due to their antiradical properties.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
