Environmental life cycle assessment of cereal and bread production in Norway

Abstract

We assessed the environmental impacts of producing bread, as delivered to the consumer, assuming the use of Norwegian ingredients only. Ten impact categories, including global warming potential (GWP), were quantified by mixed modelling and life cycle assessment. Firstly, we quantified the impacts of growing barley, oats, winter and spring wheat on 93 farms that were representative of the main cereal production regions in Norway. We used wide system boundaries, which included all relevant processes occurring both pre-farm and on-farm. Secondly, we assessed a representative production chain for bread, including transport, milling, baking and packing processes. On-farm processes accounted for a large share of the environmental impacts attributable to the production of bread (e.g. 50% for GWP). There is thus considerable potential for environmental improvements through changes in farm management. In total, the GWP per kg of bread (freshweight) was 0.95 kg CO₂-equivalent. The environmental footprint of transport was small.

Keywords:

• Acidification
• carbon stock change
• eutrophication
• global warming potential
• regional variation

Acknowledgements

This study was funded by the Norwegian Research Council (Program: Sustainable Innovation in Food and Bio-based Industries; BIONAER). We thank Hugh Riley for critically reading the manuscript, and Jon Olav Forbord, Harald Solberg and Bjørn Inge Rostad at the Norwegian Agricultural Extension Service for their valuable information on common agricultural practices in Central Norway, northern and southern parts of Eastern Norway, respectively.