Circular Economy of Amazon Nuts: Production, Processing and New Technologies

The transition from a linear to a circular economic model is critical for the sustainability of the Amazonian bioeconomy. Although Amazon nuts (internationally recognized as Brazil nuts, Bertholletia excelsa) represent a major natural bioresource, their production chain faces structural challenges, particularly concerning the underutilization and disposal of agro-industrial residues. This narrative review analyzes the Amazon nut market, processing technologies, and supply chain, with a specific focus on biomass valorization. By evaluating the recent literature across major scientific databases, this study maps the technological readiness and feasibility of integrating a circular economy model. We critically examine alternative technologies for transforming specific residues, particularly the woody fruit pods, hard seed shells, and oil press cakes, into value-added bioproducts. Key valorization routes discussed include protein concentrates and amino acid supplements from the press cake, cellulose nanocrystals and organic panels from the hard seed shell, biosolvents, and bioenergy/biochar generation via pyrolysis. The review concludes that while the current industry remains strictly focused on kernel commerce, transitioning toward a circular model appears technically promising, but its economic feasibility remains unconfirmed for most valorization pathways. However, successful industrial implementation requires overcoming logistical supply chain barriers and advancing the technology readiness levels of these valorization pathways.