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06:08
Design of Solid-State Fermentation Systems for Polymer Hydrolytic Extracellular Enzyme Production by Filamentous Fungi
Published on: June 6, 2025
A continuous, farm-scale, solid-phase fermentation process for fuel ethanol and protein feed production from fodder
W R Gibbons1, C A Westby, T L Dobbs
1Department of Microbiology, Alcohol Fuel Research Laboratory, South Dakota State University, Brookings, South Dakota 57007.
Biotechnology and Bioengineering
|September 1, 1984
Summary
Fuel ethanol production from fodder beets using a novel solid-phase fermentation process achieved higher yields and concentrations, making beets a competitive feedstock. This method offers improved energy efficiency and lower production costs compared to conventional submerged fermentation.
Area of Science:
- Agricultural Science
- Biotechnology
- Chemical Engineering
Background:
- Conventional submerged fermentation of fodder beets for fuel ethanol yields low concentrations (3-5% v/v) due to mash viscosity.
- Low ethanol concentrations increase distillation costs and reduce energy efficiency in fuel ethanol production.
Purpose of the Study:
- To develop and test a novel solid-phase fermentation process for fuel ethanol production from fodder beets.
- To achieve higher ethanol concentrations (8-10% v/v) for more efficient distillation.
Main Methods:
- Farm-scale submerged fermentation of fodder beets.
- Development and testing of a continuous solid-phase fermentation process.
Main Results:
- Submerged fermentation yielded 70 L/metric ton (7 gal/ton) with low ethanol concentrations.
- Solid-phase fermentation achieved over 8% (v/v) ethanol, yielding 87 L/metric ton (21 gal/ton).
- Production costs for solid-phase fermentation were $0.47/L ($1.77/gal) with an energy balance of 2.11.
Conclusions:
- Fodder beets are a potentially competitive feedstock for fuel ethanol production.
- Solid-phase fermentation offers a more energy-efficient and cost-effective method compared to submerged fermentation.
- Further research is needed to optimize costs, energy balances, and co-product value.
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