2024 AIChE Annual Meeting
(161e) Life Cycle Assessment and Sensitivity Analysis of a Plant-Based Meat Alternative Containing Heme Protein
Authors
Hariteja Nandimandalam, Mississippi state university
Rui Shi, The Pennsylvania State University
According to the United States Environmental Protection Agency, beef production accounts for 38% of US agricultural greenhouse gas emissions, and 3.5% of total United States greenhouse gas emissions. To mitigate the impact of food protein production, the United States aims to advance food protein production methods with greenhouse gas emissions that are 50% or less of current methods by 2028. Meat alternatives have been developed to mitigate beef greenhouse gas emissions. One nascent additive to some meat alternatives is heme protein produced via fermentation, added to enhance flavor and verisimilitude to meat. While previous life cycle assessments of meat alternatives of ground beef have included products containing heme protein as an additive, these studies have not quantified the impact of the heme additive alone, nor its contributions to the product’s environmental impact in depth. To study the environmental impact of heme protein production, and its contribution to the impact of a meat alternative, two cradle-to-gate life cycle assessments (LCA) were conducted using material and energy inputs obtained from information provided by Motif Foodworks™. The LCA of meat alternative production compared the impact of producing the meat alternative with ground beef, using a functional unit of 1 kg of meat alternative patty following the ReCiPe 2016 impact assessment method. Heme protein production resulted in an impact of 117 kg CO2 eq. per kilogram of heme protein produced, while the plant-based meat alternative patty had an impact of 3.45 kg CO2 eq. per kilogram, 90% lower than the same quantity of ground beef. Among all environmental impact categories, the impact of the heme-containing meat alternative was lower than that of ground beef, except for freshwater ecotoxicity, which was 9% greater than ground beef. The environmental impact of the meat alternative showed sensitivity to the proportion of renewable energy in the electricity used in the process, and the agricultural practices used to grow ingredients. Key drivers of greenhouse gas emissions were determined via sensitivity analysis. Greenhouse gas emissions were most sensitive to the heme protein production rate. Electricity, ingredient procurement, and heme production parameters each affect product environmental impact and are targets for future improvements to sustainability. These results can be used to illustrate bottle necks in system sustainability and inform the public of the environmental impact of meat alternative and plant-based protein production.