About one third of the food produced globally is wasted along the food chain, representing a burden for the environment and an inefficiency of the food system. Tackling food waste is a priority on the global political agenda to guarantee food security. Defining a methodology for food waste quantification is key to monitoring progress towards the achievement of reduction targets. This paper summarises the outcomes of a workshop on food waste accounting co-organised by the European Commission's Joint Research Centre and Directorate-General on Health and Food Safety with the aim of stimulating harmonisation of methodologies, identifying challenges, opportunities, and further advancement for food waste accounting. The paper presents methodological aspects, e.g. system boundaries, reliability of data, accounting of water flows, to ensure better support to food waste policy design and interventions. It addresses all the actors of the food supply chain, governments, and research institutions.

Bread waste represents a significant part of food waste in Sweden. At the same time, the return system established between bakeries and retailers enables a flow of bread waste that is not contaminated with other food waste products. This provides an opportunity for alternative valorisation and waste management options, in addition to the most common municipal waste treatment, namely anaerobic digestion and incineration. An attributional life cycle assessment of the management of 1 kg of surplus bread was conducted to assess the relative environmental impacts of alternative and existing waste management options. Eighteen impact categories were assessed using the ReCiPe methodology. The different management options that were investigated for the surplus bread are donation, use as animal feed, beer production, ethanol production, anaerobic digestion, and incineration. These results are also compared to reducing the production of bread by the amount of surplus bread (reduction at the source). The results support a waste hierarchy where reduction at the source has the highest environmental savings, followed by use of surplus bread as animal feed, donation, for beer production and for ethanol production. Anaerobic digestion and incineration offer the lowest environmental savings, particularly in a low-impact energy system. The results suggests that Sweden can make use of the established return system to implement environmentally preferred options for the management of surplus bread.