BIOTECHNOLOGICAL UPGRADE OF FRUITS WASTE BIOMASS: A PRELIMINARY ASSESSMENT

摘要

The annual production of fruits in Navarre (Spain) and Aquitania (France) is approximately 454.123tons and vegetable production was about 1.202.762 tonnes (2003-2007 MARM and Eurostat). Considering currentproduction processes approximately 12% of the amounts processed are wastes. This percentage could be increaseduntil 40-60% depending on the process, so annual production of organic wastes could be approximately between200.000 -800.000 tonnes/annual. Kiwi, peach and strawberry by-products from fruits food processing industry weretested as possible feedstocks for 2nd generation biofuels production and bioactive compounds extraction. In abiorefinery concept, fruits residues were previously subjected to different environment friendly extractions to obtaintheir high added value contents, and afterwards, wastes from these processes were upgraded for bioethanol and/orbiomethane production. In this work, bioactive compounds were extracted from selected fruits by-products.Characterization of antioxidant capacity and different vitamins were carried out. The extraction of these compoundswas made by supercritical fluid extraction (SFE) and Spray-Drying technology (SD). According to bioethanolproduction, a compositional analysis of the wastes was done. It has been proven that concentrations of soluble sugarsof fruits ca increase 30 -100% by enzymatic hydrolysis depending on the fruit increasing considerably bioethanolyields. According to biogas production, methanogenic potential varies between 250 and 300 Nm~3/tVS for fruitwastes. The residues of vegetables ranged from 320 to 550 Nm~3/tVS. A test pilot reactor has shown that the codigestionwith other fermentable waste is certainly the best solution to produce biogas energy. This project wasfunded by Interreg IV A program and Navarre-Aquitania funding during years 2007-2009 (DOVAREC II).