Circular Bioprocessing of Ethanol Carbon Dioxide and Thin Stillage for Sustainable Food Ingredient Production Using Microalgae

Algae Solutions for Carbon Emissions

Carbon dioxide emissions from bioethanol production and other industrial activities represent a significant environmental challenge in Minnesota, while existing carbon capture technologies remain energy intensive and costly.

Microalgae offer a natural carbon capture solution by efficiently converting carbon dioxide into biomass and valuable biochemicals. However, conventional microalgal cultivation systems relying on single species often suffer from limited nutrient utilization efficiency and suboptimal carbon capture performance. This project addresses this barrier by developing a mixotrophic co-cultivation platform using Euglena gracilis (EG) and Chlorella vulgaris (CV) that integrates photosynthetic carbon fixation with heterotrophic utilization of organic nutrients.

By quantifying carbon dioxide utilization efficiency, biomass productivity and ingredient yields, this research will assess the feasibility of transforming ethanol byproducts into sustainable food ingredients.

Project Goals

• Develop a scalable mixotrophic co-cultivation system for EG and CV to achieve ≥60 percent carbon sequestration
• Optimize enzyme modification of thin stillage to create a cost effective and nutrient rich medium that enhances algal growth
• Characterize harvested biomass for protein, lipid and paramylon to evaluate its potential as sustainable ingredients for functional foods, nutraceuticals and bio-based materials
• Conduct Life Cycle Assessment and Techno Economic Analysis to evaluate the scalability, sustainability and economic viability of the proposed process