Implementation of resource supply risk characterisation factors in the life cycle assessment of food products: Application to contrasting bread supply chains

In addition to generating environmental impacts, food systems are vulnerable to shortages of the resources on which they rely (e.g. critical minerals, water and land). To eco-design these systems, their environmental footprints and vulnerabilities to resources must be assessed simultaneously. Resource supply risk methods have been applied to life cycle assessments (LCAs) of high-tech products to provide information on resource accessibility. The aim of this paper is to discuss the applicability of these methods to the LCA of food products.

Supply risk characterisation factors (CFs) are derived from the two acknowledged resource criticality methods of (i) the Joint Research Centre (JRC) and (ii) the Yale University. These methods characterise mineral, land and water resources, which are essential for agricultural products. CFs are matched with life cycle inventory (LCI) data, and a comparative LCA on both environmental impacts and resource supply risk is performed on three contrasting bread supply chains. These supply chains differ by agricultural practices, flour milling and bread baking processes, as well as transport distances between intermediaries.

The results of the case study show that trade-offs can occur between environmental impact and resource supply risk. Indeed, the supply chain with the greatest environmental impacts is also the one with the lowest mineral and water supply risk potential. Analysis of the results indicates that fertilisers contribute the most to the mineral supply risk of agricultural products, that land supply risk potential is due to agricultural production and forestry for energy and packaging, and that the water supply risk potential is mainly related to electricity production for baking. The comparison between the Yale and JRC methods highlights differences in modelling choices, mainly due to their different coverages and scopes.

This case study highlights the value of considering resource supply risks as a complement to conventional LCA of food products, as it makes it possible to identify potential trade-offs between environmental impacts and vulnerability to resource supply shortage. The development of additional case studies, using other supply risk methods and including processed resources such as agricultural products, would enable further research on food system criticality.