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Fuel alcohol production: optimization of temperature for efficient very-high-gravity fermentation
1Department of Applied Microbiology and Food Science, University of Saskatchewan, Saskatoon, Saskatchewan, Canada S7N 0W0.
Applied and Environmental Microbiology
|March 1, 1994
Summary
Increasing temperature and adding urea speeds up wheat mash fermentation, with optimal ethanol production at 27°C. These findings aid very-high-gravity fermentation technology assessments.
Area of Science:
- Biotechnology
- Fermentation Science
- Biochemistry
Background:
- Wheat mash fermentation is crucial for ethanol production.
- Optimizing fermentation conditions is key for industrial efficiency.
- Very-high-gravity (VHG) fermentation presents unique challenges and opportunities.
Purpose of the Study:
- To investigate the impact of temperature and dissolved solids on wheat mash fermentation time and ethanol yield.
- To evaluate the effect of urea supplementation on fermentation kinetics and ethanol production.
- To determine the optimal conditions for VHG wheat mash fermentation.
Main Methods:
- Wheat mash fermentation experiments were conducted across a range of temperatures (17–33°C) and dissolved solid concentrations (14.0–36.5 g/100 ml).
- Urea was added to supplemented mashes to assess its effect on fermentation rate and ethanol yield.
- Ethanol yield and fermentation time were measured under various conditions.
Main Results:
- Fermentation time decreased with increasing temperature but increased with higher dissolved solids.
- Ethanol yield was largely unaffected by temperature and dissolved solids within the tested ranges.
- Urea supplementation accelerated fermentation, reduced completion time, and slightly increased ethanol production.
- The optimal temperature for ethanol production in urea-supplemented VHG wheat mash was 27°C.
Conclusions:
- Temperature and dissolved solids concentration significantly influence wheat mash fermentation time.
- Urea supplementation is a viable strategy to enhance fermentation efficiency and ethanol yield in VHG processes.
- The findings provide valuable data for the industrial application of VHG fermentation technology.
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