Prospects and Perspectives for Producing Biodiesel, Bioethanol and Bio-Chemicals from Fruit Waste: Case Studies in Brazil and Serbia

Abstract

Fruits are some of the most valuable agro-industrial products with high nutritional value and considered very healthy food. Nevertheless, fruit residues resulting from fruit processing represent organic waste and can make up almost 1/2–3/4 of the entire year of fruit agribusiness production. These semi-solid fruit residues are being landfilled at an alarming rate and can even become dangerous organic wastes that might cause pathogen proliferation and disturb environmental microbiota. In developing countries, fruit waste is even greater because of low or no investment in refrigerated transport and cold storage facilities after harvest of the fresh fruit. Therefore, there is a strong appeal in reusing this waste and adding-in higher value to the fruit residues such as manufacture of nutritive supplements, biochemicals and biofuels. In the area of biofuel research, by far the bioethanol production from the fruit residues is an interesting topic to discuss and explore, as well as biodiesel production, which depend on chemical composition and characteristics of different types of fruit biomass. Some fruit derived biopolymers such as pectin, lignin, hemicelluloses and cellulose based polymers are very valuable commodities already explored. But some fine chemical products such as pigments, fragrances, essential oils, organic molecules, and many bioactive substances can be obtained from fruit residues and even if not the greatest in quantity, for sure may add-in great value into fruit agri-business. Brazil is one of the top-five world fruit producers and leading the world market of orange fruit production, which is one of the biomasses taken as an example for biochemicals and bioethanol production. On the other side, fruit residues in Serbia can become valuable resources for biodiesel and other commodities production. This chapter brings some important and updated state-of-the-art processes for exploring fruit waste for biofuel and biochemicals production in the laboratory scale and prospection about bioeconomy for industrial exploitation. Finally, the brief discussion on liquid and solid residues generated in some of the proposed processes are disclosed.KeywordsFruit wasteBiopolymersActive ingredientsFlavonesPigmentsBiofuels