Upcycling as a circular strategy for food waste valorization in developing countries: A systematic review and the upgrade strategic framework

Abstract Food waste remains a critical environmental, economic, and social challenge worldwide. As a circular economy strategy, upcycling offers innovative pathways to add value to food waste and enhance the sustainability of food systems. This study integrates a systematic literature review of 86 articles published between 2016 and 2023 with an empirical investigation involving 48 restaurants in two developing countries. The findings highlight significant advancements in upcycling technologies and applications but also reveal persistent barriers, particularly in stakeholder engagement, policy frameworks, and economic viability. Despite growing academic attention, empirical studies have shown low adoption of upcycling practices in the restaurant sector, with limited awareness and technical capacity as the primary obstacles. The study recommends targeted public policies that emphasize education, technical training, and incentives to promote the adoption of upcycling across food service and broader supply chains. This research provides a foundation for advancing circular food systems in developed and developing contexts by bridging theoretical insights and practical challenges.