Assessing In-Flight Food Waste Management Practices of Major Airlines Operating Direct Flights to Auckland: A Comparative Study Under New Zealand’s Border Security

In-flight food waste has become an important environmental, operational, and biosecurity challenge for the international aviation industry. This study examined how major airlines operating direct flights to Auckland, New Zealand (Air New Zealand, Emirates, Qantas, Singapore Airlines, and China Southern Airlines) manage in-flight food waste within New Zealand's stringent biosecurity framework and how these practices align with broader sustainability and Circular Economy objectives. Guided by the Circular Economy framework, the research adopted an interpretivist qualitative case study design based exclusively on secondary documentary data. Documentary evidence was collected from airline sustainability reports, annual reports, regulatory publications, airport operational documents, and industry reports. The data were analysed using hybrid thematic analysis, combining deductive and limited inductive coding with the support of NVivo 15.4. The analysis identified eight interconnected themes: Food Waste Reduction, Circular Economy, Sustainability Strategies, Waste Management Practices, Biosecurity Compliance, Regulatory Constraints, Stakeholder Collaboration, and Resource Efficiency. The findings indicate that all five airlines have integrated food waste reduction into their sustainability and operational strategies through initiatives such as meal forecasting, waste monitoring, inventory optimisation, resource efficiency, sustainable packaging, and the use of digital technologies. However, the study also found that New Zealand's strict biosecurity regulations governing international catering waste significantly constrain opportunities for recycling, composting, food redistribution, and the broader implementation of the Circular Economy. The study concludes that sustainable airline food waste management requires balancing environmental sustainability with national biosecurity responsibilities. While airlines demonstrate a strong commitment to improving sustainability, implementing Circular Economy principles successfully depends not only on organisational initiatives but also on stakeholder collaboration, technological innovation, and supportive regulatory frameworks. This dissertation adds to the growing body of knowledge on sustainable aviation by providing practical and theoretical insights into managing in-flight food waste within a highly regulated biosecurity environment.