Italian scientists have devised an innovative and economically feasible biorefinery that can squeeze more chemicals out of the mountains of grape waste produced during wine production.
Last year around 28 billion litres of wine were produced globally—enough to fill over eleven thousand Olympic sized swimming pools. But after pressing the last of the juice from the grape, a whole lot of skins and seeds are left—around 5 million tons of the stuff.
Traditionally this waste, known as pomace, is redistilled to produce spirits such as grappa. But changes in EU policy have reduced the subsidies given to distillers in an attempt to get more from this resource. Though useful chemicals such as polyphenols (natural antioxidants used in cosmetics and preservatives) or methane-rich biogas can be extracted from red grape pomace, you’d be hard pressed to turn a profit from existing single-product valorisation processes.
Raise a glass then to Lorenzo Bertin and colleagues at the University of Bologna, who have developed a multi-purpose biorefinery which not only produces polyphenols, but fatty acids, biopolymers, and biomethane too. Using supercritical carbon dioxide, the team extracted the useful polyphenols and sugars, before using anaerobic digestion to produce other useful compounds such as fatty acids. The leftover solid waste underwent further microbial treatment to produce methane, whilst any remaining liquid waste was aerobically fermented to produce environmentally friendly polymeric materials. Bertin’s biorefinery is striking for the sheer range of products it is able to extract from a single integrated process—making this green approach much more industrially viable
REF: scientificamerican.com
No comments:
Post a Comment