Developing a sustainable food industry is the global consensus regarding climate change and food security. This present study aims to take account of life cycle-carbon footprints for the environmental performance/labeling of 20 food products commissioned by the flour processing factory in Pyongyang and to give lessons for the rest consumer products. This study conducts analyses of Functional Units (FUs) and hotspots with a couple of questions of how much are life cycle-carbon footprints per FU of the food products investigated from the company? and what are the key hotspots (primary, secondary, and tertiary) connected to the life cycle phases? The results show that the carbon footprints of food products vary in a range of 2050–5080 g CO2eq. depending on the defined FUs: mass-based FUdry (dry basis), mass-based FUtotal (total basis), and economic value-based FUpri (price basis). The results also reveal that both the mass-based FUdry and economic value-based FUpri might lead to proper environmental benchmarking/labeling of food products, when compared to the mass-based FUtotal that could definitely affect food LCAs. In addition, the results indicate that three subsystems in 20 product systems are identified as environmental hotspots to have improvement potential: flour subsystems (13 primary hotspots), washing and wastewater subsystems (12 secondary hotspots), and electricity subsystems (14 tertiary hotspots), while representing average contributions of 28.58, 23.34 and 16.23% to the total carbon footprints, respectively. The findings could encourage LCA practitioners and commissioners to implement a sustainable policy for environmental performance/labeling of crop-based food products and give lessons for the rest consumer products.
