The Unsold Food Pathway: Cold Storage Facilities and Dietary Diversity among Migrant Food Vendors in Nanjing, China

Previous studies have largely overlooked the potential impact of cold storage facilities on household dietary diversity. To address this gap, this study draws on survey data collected from migrant food vendors in wet markets in Nanjing City, China. It proposes two pathways linking cold storage sufficiency to vendors’ household dietary diversity and tests these mechanisms using path analysis based on Generalised Structural Equation Modelling (GSEM). The results show that greater sufficiency of cold storage facilities led to higher dietary diversity in migrant food vendors’ households, primarily by reducing the consumption of unsold food. In contrast, no significant effect is found along the pathway linking storage facilities to business hours, time allocated to food-related activities, and dietary diversity. By uncovering the “unsold food” pathway, the study contributes to urban food security and food environment research by demonstrating that food system actors may experience limited dietary diversity despite operating in food-rich environments. The paper calls for policy measures, such as subsidised cold-storage equipment and improved electricity use, to reduce food spoilage, improve dietary diversity among vendors, and help address hidden hunger in urban settings.