Prospective life cycle assessment of mycelium protein from submerged fermentation: The role of energy systems and residual substrates

Mycelium from basidiomycetes is gaining attention as a promising alternative protein source to address the rising global demand for sustainable proteins. This study presents a prospective life cycle assessment (LCA) of a novel food application based on Flammulina velutipes (FVE) mycelium produced via submerged fermentation using potato pulp as a substrate – a side stream from the food industry. In addition to a pilot-scale base case, three future scenarios for 2030 and 2050 (best-case, predictive, worst-case) were developed based on primary process data, expert estimates of efficiency improvements, and projected future energy mixes. Results show that, in the best-case scenario, the climate change impacts could be reduced by up to 95% by 2050 compared to the base case, primarily through process optimization and a decarbonized energy supply. Uncertainty analysis confirmed the projected reduction in climate change impacts across future scenarios and identified agitation efficiency as the key improvement priority for 2030, while thermal energy efficiency becomes critical by 2050. Through the application of a structured prospective LCA to an emerging mycelium-based food production, this study first identifies the key prospective elements and uncertainties that need to be considered. The results underscore the potential of mycelium as a sustainable protein source and emphasize the importance of early-stage process optimization and alignment with renewable energy supply to fully realize its environmental benefits.