Food waste generation at households and the resulting life cycle environmental impacts: A case study of fresh and frozen broccoli

Abstract

Food waste has serious environmental and economic consequences, making it a global issue with growing attention from academia, industry and policy makers. The key to reduction or better management of food waste is understanding the quantities and composition of food waste at each stage of the food supply chain. In developed countries, it is reported that the highest percentage of food loss/waste happens in the post-consumption stage, especially at households. Understanding the composition of avoidable food waste at households is important to assess the applicability of food preservation techniques, such as freezing, to reduce the life-cycle environmental impacts of the food system. Thus, the current study aims to understand the impacts of food waste across the supply chain, by comparing the life-cycle environmental impacts of fresh and frozen produce, using broccoli as a case study vegetable. This aim was achieved in two stages. First, 16 samples of green bin waste generated at households in the Region of Waterloo were analyzed to understand the composition of the avoidable food waste fraction. The findings suggest that 43% of all food waste is avoidable and 86% of avoidable food waste is plant-based, indicating that fresh fruits and vegetables are the most frequently wasted food item in households. Since frozen vegetables are known to generate comparatively less food waste than their fresh counterparts due to increased shelf life and ability to utilize ‘ugly’ produce, it is important to understand the life-cycle environmental impacts of fresh and frozen produce, taking into account how waste occurs in each supply chain. Broccoli was selected as the case study vegetable and a comparative life cycle assessment (LCA) was carried out to analyze the life-cycle environmental performance of fresh and frozen broccoli produced and consumed in Ontario. Findings suggest that within the study context, fresh broccoli performs better in four impact categories; acidification, global warming, ozone depletion and resource depletion, whereas frozen broccoli performs better in eutrophication. Therefore, the reduced FW that occurs in frozen broccoli supply chains is not sufficient to offset the environmental impacts of energy use for additional processing and frozen storage. However, the need for more rigorous research is emphasized for better understanding of the fresh and frozen supply chains, and how to minimize impacts from associated food waste.