Abstract
The transition towards a circular economy in the food sector is crucial to meet society’s sustainability challenges. One promising approach is upcycling of food loss and waste sidestreams (FLWS) which can be converted into raw materials for another cycle. This paper focuses on the circular supply chain involved in upcycling of FLWS through bioconversion by insect larvae. Using a two-step upcycling strategy, FLWS is converted into substrates for insect larvae. The larvae are subsequently processed into protein meal that is used as ingredients in livestock feed, thus creating a circular supply chain. The paper explores the consequences this approach has for the development of the circular food supply chain and reverse logistics. The study provides an overview of the current state of knowledge, presents a case study from a poultry supply chain, and synthesizes key concepts and insights into a conceptual logistics model. The model outlines the actors, processes, and material flows involved in the circular supply chain. A research agenda proposes topics to guide future studies towards full-scale realization of the concept, highlighting both structural and planning issues. Topics include development of suitable systems for reverse material flows and sorting and storage solutions, determination of how to integrate FLWS and circular materials into existing production capacities, and planning issues related to balancing supply and demand, particularly related to the predictability of volumes, timing, and yield. The paper concludes by highlighting the theoretical contributions and practical implications of the study.