Improving Small-Scale Value Chains in Tropical Forests. The Colombian Case of Annatto and Açai

Tropical forests provide a development opportunity for communities that subsist on small crop value chains. Annatto and açai are exotic fruits used as a source of natural dyes and high-calorie beverages, respectively. However, the processing of these fruits generates considerable residues that have a negative environmental impact and can be used for biofuel production. This work elucidates valorization schemes of annatto and açai in integrated raw material systems to improve the value chains of tropical forest fruits. The economic and environmental pre-feasibility for producing annatto dye, açai powder, and biogas was evaluated through experimental and simulation data. As the main results, it was obtained that the extraction of dye by abrasion shows to be a methodology with high carotenoid content. Additionally, freeze-drying improves the antioxidant activity and the content of polyphenols and anthocyanins on açai pulps. The processing residues of both fruits were used as the substrate for anaerobic digestion purposes and as a low-cost valorization alternative, showing the best biogas yields for the exhausted annatto seed. The experimental results were fed to the simulation of small-scale processing schemes based on exotic fruits. The main results demonstrated that working in batch six-monthly schemes allows for obtaining economic feasibility based on fruit production lower than the national scale. Although freeze-drying is an expensive process, the production of açai fruit powder is the most cost-effective scenario. From an environmental perspective, the disposal of digestate as waste drastically affects the environmental analysis. However, for the five environmental indices analyzed, producing açai powder, biogas, and digestate valorization as fertilizer is the scenario with the lowest environmental impact. Finally, the results were analyzed regarding the impact on the Sustainable Development Goals (SDGs) of the region. This work demonstrated that small-scale schemes based on the processing of tropical forest fruits improve the regional agribusiness performance by strengthening the value chain considering economic, environmental, and social issues. Graphical Abstract