Climate Impact of Plant-based Meat Analogues: A Review of Life Cycle Assessments

Abstract

The transition towards more plant-based diets is identified as an important measure for limiting dietary climate impact. Plant-based meat analogues (PBMAs) have been proposed as a viable lower carbon alternative to meat, and its market is rapidly growing globally. However, knowledge about the climate impact of PBMAs in relation to other foods is currently limited due to the challenge of comparing life cycle assessments (LCAs) using different methods. The aim of this study was to review the climate impact of PBMAs based on LCAs published up to 2021. Original LCA data were recalculated to harmonize differences in method choices among studies and presented as the climate impact of final products at factory gate. The median climate impact of PBMAs was estimated at 1.7 kg CO2 eq./kg of product with a more than fourfold variation in impact (0.5–2.4 kg CO2 eq./kg product). Climate impact per protein content of the final product varied from 0.4 to 1.2 kg CO2 eq./100 g protein with a median impact of 0.8 kg CO2 eq./100 g protein. Cultivation of raw materials and manufacturing were identified to be responsible for a large proportion of GHG emissions up to factory gate. However, the assessment of climate impact in the production chain was challenged by the level of detail of data provided. A transparent reporting strategy regarding the specific stages in the supply chain, method choices and product information is recommended to facilitate identification of hot spots to target for improved climate performance of future PBMAs and to enable accurate comparisons between studies. It could further be concluded that current scientific knowledge on the climate impact of PBMAs is based on a limited number of LCAs that often rely on a combination of secondary data and collected data at production scale or from pilot-scale production facilities. Future LCAs of PBMAs would benefit from additional assessments of commercial production using region- and site-specific data.