Contribution of food loss to greenhouse gas assessment of high-value agricultural produce: California production, U.S. consumption

Abstract

Abstract Food loss (wasted and spoiled food) increases the burden on resources and environmental impacts throughout the entire food chain. This study describes and deploys a model and identifies data sources for estimation of greenhouse gas (GHG) emissions associated with food loss from farm production, delivery and refrigeration, retail sale, household consumption, and waste management in the United States using four California-grown high-value produce as case studies. The ratios of food wasted to food produced are 50%, 60%, 50%, and 64% for avocados, celery, lemons, and strawberries, respectively, and the differences are largely influenced by consumer-level and on-farm food loss. From the consumption perspective, this means, for example, that 1.8 units of strawberries are wasted for every unit consumed. The packaging material is a significant environmental offender, contributing, e.g. 52% to the total emissions (without food loss) for strawberries. End-of-life analysis of wasted food and packaging covers the common waste management practices: landfilling, composting, anaerobic digestion, incineration, and recycling. Uncertainties in the data are assessed through Monte Carlo simulation. With the consideration of food loss, the total GHG emissions from the entire life cycle of strawberries, celery, avocados, and lemons increase by 93%, 62%, 56%, and 53% to 0.26, 0.038, 0.061, and 0.058 kg CO2 eq. per one serving size, respectively. Emissions from the annually wasted strawberries, avocados, celery, and lemons in California amount to 76, 24, 12, and 12 000 tons of CO2 eq., respectively. Fourteen percent of the world’s population could have a serving of strawberries just from the annually wasted strawberries in California. However, wasteful consumer action can be even more significant. Emissions from a typical driving scenario to a store to purchase only one produce exceeds the emissions associated with all four produce combined. Reducing food waste during consumption and the environmental impacts of packaging should be prioritized.