RESUMO
In this paper, a sustainability evaluation method for food-packaging systems is proposed. First, food waste due to poor emptiability was determined. Then, these quantities were included in life cycle assessments (LCA) and life cycle costing (value added, VA) of the products. Finally, LCA and VA results were combined using multi-criteria decision analysis, Technique for Order by Similarity to Ideal Solution (TOPSIS), in order to identify the most sustainable food packaging system. As a case study, four different ketchup products were examined. For ketchup in polypropylene bottles, FLW resulting from poor emptiability ranged from 13.12% (±2.05) to 28.80% (±3.30) respectively, while this was only 3.85% (±0.41) for ketchup packaged in glass. After integrating the emptiability results into life cycle assessments, this resulted in greenhouse gas emissions of 5.66 to 9.16 kg CO2eq per 3.80 kg consumed ketchup, the average consumption per capita in Austria. Importantly, poor emptiability of the examined products led to greater environmental impacts than the associated packaging. While greater product loss also pushes up the costs for consumers, it contributes to more value added to the economic system, which is in stark contrast to the goal of decoupling the economy from resource consumption.