Fruit and vegetable postharvest waste in Tanzania: A review of occurrence, sources, environmental impacts, and contextual utilization pathways

Fruit and vegetable postharvest waste (FVPW) represents a significant environmental and economic challenge in developing countries, where supply-chain inefficiencies and limited infrastructure contribute to substantial losses. While numerous technologies for FVPW utilization exist, integrated assessments that connect waste occurrence, environmental impacts, utilization pathways, and contextual feasibility within specific national settings remain limited. In this review, we synthesized evidence on the sources, environmental impacts, and valorization options of FVPW and evaluated their contextual feasibility within the Tanzanian context. A combined scoping and integrative review approach was employed using peer-reviewed literature, followed by a qualitative feasibility analysis considering technological readiness, cost, environmental benefit, infrastructure needs, and scalability potential. The findings revealed a hierarchy of implementation: High-readiness options such as composting and animal feeding provide immediate and scalable solutions, whereas medium- and low-readiness pathways, including anaerobic digestion, biochar production, bioethanol, bioactive compound extraction, and bioplastic synthesis, offer higher environmental and economic value but face infrastructural and institutional barriers. The analysis suggests that a phased transition strategy, prioritizing readily implementable technologies while progressively strengthening technical capacity and market systems, offers the most realistic pathway toward circular FVPW management. Furthermore, the study highlighted that the scalability of advanced valorization pathways is strongly dependent on access to appropriate financing mechanisms, including green finance instruments, blended finance models, and sustainability-linked investment frameworks. These insights provide practical guidance for policy, research, and investment aimed at enhancing sustainable postharvest waste utilization in Tanzania.