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Purpose In light of the sustainable diet debate, we conducted a large-scale regionalised LCA to answer the following questions: (i) does the climate advantage hypothesis of plant-based fat spreads and creams over dairy butter and cream hold regardless of the variabilities of product recipes, geographies and the influence of land use change (LUC)? (ii) Considering the climate-water-land nexus, is there a risk of shifting impacts from climate to water scarcity and land occupation, and what are the key opportunities for impact mitigation? Methods A framework for conducting a large-scale regionalised LCA was developed and applied to compare the environmental impacts of 212 plant-based fat spreads, 16 plant-based creams and 40 dairy alternatives sold in 21 countries per 1 kg of product. Data was compiled for different product recipes, key ingredient sourcing countries, production factory locations, energy mixes, packaging designs, transportation and end-of-life scenarios. Spatially (archetype) differentiated agricultural life cycle inventory data were generated, as well as LUC emissions for agricultural ingredients. A total of 18 environmental indicators were assessed. Results and discussion All plant-based spreads had a significantly lower climate impact than butter, with and without LUC inclusion. The regionalised analysis highlighted large variabilities across products, ranging from 0.98 to 6.93 (mean 3.3) kg CO2-eq for 212 plant-based spreads and 8.08 to 16.93 (mean 12.1) kg CO2-eq for 21 dairy butter with 95th confidence interval. The main drivers of GHG emissions for plant-based products are oilseed farming and the associated LUC emissions, which can vary significantly depending on type of oilseeds, quantity and sourcing country; in the worst-case scenario, the climate advantage is no longer valid due to LUC. Thus, the inclusion of LUC is essential for a robust assessment and hotspot identification. Overall, the risk of shifting impact was small, as most of the plant-based spreads also had lower impacts for water scarcity footprints and land occupation; 8 of the 212 products were not lower, due to oilseed ingredients with high embodied impacts. Conclusions This study confirmed that plant-based spreads had lower climate, water and land impacts than butter, despite variability of product recipes, geographies and influence of LUC. This research offers a framework for performing regionalised agricultural LCA for a large portfolio of products thereby enabling identification of inter-product variabilities and hotspots for the development of mitigation strategies. Key mitigation opportunities include reducing oilseed ingredients' embodied impacts by optimising product recipe design and adapting supply chain sourcing and agricultural practice.
Marc Vielle, Sigit Pria Perdana
Sergi Aguacil Moreno, Martine Laprise, Sara Sonia Formery Regazzoni