Understanding Food Waste Sorting Practices: Insights from a Systematic Review

Approximately 2.5 billion tons of waste are generated annually worldwide, with food waste constituting a significant portion: 88 million tons in the European Union (EU) alone. Food waste has severe societal, economic, and environmental consequences, contributing 15–16% of greenhouse gas (GHG) emissions from the food supply chain. In response, many countries, including EU member states, the United States of America (USA), and China, have introduced policies mandating food waste sorting. These regulations are informed by scientific research on waste prevention, environmental impact assessments, and cost–benefit analyses of waste reduction strategies. For example, studies on organic waste treatment technologies, economic incentives for waste sorting, and the effectiveness of landfill bans have influenced the development of the EU Waste Framework Directive (2008/98/EC), China’s National Waste Classification Policy (2017), and the USA Food Recovery Act (2015). As waste management continues to evolve, understanding the economic, technological, and policy dimensions of food waste sorting remains crucial for achieving sustainable development and circular economy goals globally. This study systematically reviews the international literature on food waste sorting, analyzing sorting behaviors and identifying theoretical frameworks that explain these behaviors. Using the PSALSAR systematic review methodology, 67 relevant studies from diverse geographic regions were analyzed. The findings highlight the critical influence of external factors in shaping sorting behaviors, such as financial incentives and infrastructure, alongside internal drivers, such as environmental awareness and social norms. While external measures often yield immediate compliance, internal motivation fosters long-term behavioral changes. Moreover, significant regional and cultural variations in food waste sorting practices were identified. The Theory of Planned Behavior (TPB) emerged as a dominant framework in the study of waste sorting behaviors, often complemented by other models such as Social Cognitive Theory (SCT). Policy recommendations emphasize the need for tailored interventions that address regional and demographic differences, community-driven educational initiatives, and the integration of innovative waste sorting technologies. Future research should focus on assessing the economic and psychological impacts of waste sorting policies across different socio-cultural contexts and exploring innovative strategies to enhance global public participation in food waste management.