Circular Urban Food Systems: Innovations in Food Waste Valorization for Sustainable Cities

About this Research Topic

Background

The transformation of urban food systems, including urban agriculture and food waste valorization, is essential to achieving sustainable, resilient, and climate-smart cities. This Research Topic aims to spotlight cutting-edge research and applied innovations that convert food waste—from farm to fork—into valuable products and circular resources, thereby strengthening the sustainability of urban food systems.

Urban centers generate significant quantities of food waste at multiple stages, including agricultural surpluses in peri-urban areas, byproducts from food manufacturing, losses in distribution and retail chains, and post-consumer leftovers. While food waste has traditionally been treated as an unavoidable burden, it is increasingly recognized as a critical feedstock for creating value through circular economy strategies. This Research Topic seeks to bring together interdisciplinary work that explores food waste not as an end-of-pipe problem, but as a pivotal entry point for innovation in urban agriculture and sustainable food systems.

We welcome original research, case studies, reviews, and policy analyses that address themes including, but not limited to:

Repurposing food waste into animal feed, compost, or biofertilizers for urban and peri-urban farming

Biotechnological or low-tech methods for producing food ingredients, nutraceuticals, or functional materials from food waste streams

Circular economy models that integrate food waste valorization into urban farming systems, including vertical farms, rooftop agriculture, aquaponics, and hydroponics

Tech-enabled, data-driven, or community-led solutions for separating, collecting, and transforming household, institutional, or commercial food waste

Urban symbiosis models and industrial ecology approaches connecting food, energy, and waste systems in cities

Innovations in decentralized or neighborhood-scale food waste processing systems (e.g., micro-biodigesters, community composting hubs)

Use of AI, IoT, or blockchain technologies in optimizing food waste tracking, logistics, and upcycling

Cross-sector collaborations for food waste valorization between urban planners, designers, local governments, and agri-tech startups

Economic, environmental, and social impact assessments of food waste valorization strategies across diverse urban contexts

Consumer behavior, education, and social innovation in reducing and repurposing food waste

Legal, institutional, and governance frameworks enabling circular urban food systems

Public-private partnerships and policy instruments that support scalable, inclusive valorization initiatives

Case studies of successful implementation in cities of the Global South and Global North, with attention to equity, scalability, and climate resilience

This Research Topic will serve as a platform for emerging and established researchers to showcase transformative approaches that bridge the gap between waste reduction and food system regeneration. By focusing on food waste valorization within the context of urban agriculture and urban food systems, this Research Topic aligns with broader goals of food security, climate action, and sustainable city development. We especially encourage contributions that highlight inclusive, scalable, and context-sensitive innovations from both the Global North and South. Research article submissions for this Research Topic are expected to focus on well-defined research hypotheses and questions using systematic and replicable methodologies.

Article types and fees

This Research Topic accepts the following article types, unless otherwise specified in the Research Topic description:

• Community Case Study
• Conceptual Analysis
• Data Report
• Editorial
• General Commentary
• Hypothesis and Theory
• Methods
• Mini Review
• Opinion
• ... View all formats

Articles that are accepted for publication by our external editors following rigorous peer review incur a publishing fee charged to Authors, institutions, or funders.

Article types

This Research Topic accepts the following article types, unless otherwise specified in the Research Topic description:

• Community Case Study
• Conceptual Analysis
• Data Report
• Editorial
• General Commentary
• Hypothesis and Theory
• Methods
• Mini Review
• Opinion
• Original Research
• Perspective
• Policy and Practice Reviews
• Policy Brief
• Review
• Systematic Review
• Technology and Code

Keywords: Urban agriculture, Circular food systems, Food waste valorization, Food waste management, Sustainable cities, Resource recovery, Organic waste, Biofertilizers, Food upcycling, Waste-to-value, Urban metabolism, Community composting, Agri-food innovation

Important note: All contributions to this Research Topic must be within the scope of the section and journal to which they are submitted, as defined in their mission statements. Frontiers reserves the right to guide an out-of-scope manuscript to a more suitable section or journal at any stage of peer review.

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