Carbon Footprint of Food Products

Abstract

The food system has been identified as one of the major contributors to climate change. The main sources of greenhouse gas emissions are nitrous oxide (N2O) from soils, methane (CH4) from enteric fermentation in animals, and carbon dioxide (CO2) from land use change, such as deforestation. Emissions also arise from manure management, mineral fertilizer production, rice cultivation, and energy use on farms and from post-farm activities such as processing, packaging, storage, distribution, and waste management. With increasing awareness of climate change, calculating the carbon footprint (CF) of food products has become increasingly popular among researchers and companies wanting to determine the impact of their products on global warming and/or to communicate the CF of their products to consumers. This chapter discusses issues that are especially relevant when calculating the CF of food products, such as the choice of functional unit, which is challenging owing to the multifunctionality of food. Other issues concern how to include emissions arising from indirect land use change and removal of CO2 from the atmosphere by carbon sequestration in soils into CF calculations. Causes of the large uncertainties associated with calculating the CF of food products and ways to handle this uncertainty are also discussed and examples of uses and results of CF of food products are presented. Despite the large uncertainties, it is clear that the differences in CF between different types of food products are very large. In general, the CF of livestock-based products are much larger than those of plant-based products. CF information on food products may be useful in business-to-business communication, for professionals in the retail sector and in public procurement.