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Updated: Aug 6, 2026
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Operation of a Benchtop Bioreactor
Published on: September 12, 2013
Foam control in fermentation bioprocess: from simple aeration tests to bioreactor
A Etoc1, F Delvigne, J P Lecomte
1Dow Coming s.a., Rue Jules Bordet, Parc Industriel - Zone C, 7180 Seneffe, Belgium.
Applied Biochemistry and Biotechnology
|August 19, 2006
Summary
A new dynamic sparge test effectively screens foam control agents for Yarrowia lipolytica fermentation. A silicone/organic blend antifoam demonstrated superior performance compared to organic or silicone-based agents during extended fermentation.
Area of Science:
- Biotechnology
- Chemical Engineering
- Industrial Microbiology
Background:
- Foam formation is a significant challenge in industrial fermentation, impacting process efficiency and product yield.
- Effective foam control agents (antifoams) are crucial for optimizing bioreactor operations, particularly in large-scale microbial production.
- Yarrowia lipolytica is a key microorganism used in industrial biotechnology, and its mass production often involves significant foaming issues.
Purpose of the Study:
- To develop and validate a simple laboratory test for screening antifoams in a Yarrowia lipolytica fermentation system.
- To compare the efficacy of three distinct antifoam formulations (organic, silicone-based, and silicone/organic blend) under dynamic aeration conditions.
- To correlate antifoam performance with changes in fermentation broth properties, such as protein content and foam stability.
Main Methods:
- Development of a "dynamic sparge test" simulating bioreactor gas-liquid hydrodynamics by sparging air into a foaming medium.
- Comparative analysis of three antifoams: TEGO AFKS911 (organic), DC-1520 (silicone-based), and a silicone/organic blend.
- Monitoring antifoam capacity over fermentation time and correlating performance with broth composition (protein content) and foam stability.
Main Results:
- Significant differences in antifoam efficacy were observed among the tested agents.
- The performance of organic (TEGO AFKS911) and silicone-based (DC-1520) antifoams decreased notably over the fermentation period.
- A silicone/organic blend formulation exhibited sustained foam control with minimal performance degradation, even with increasing protein content and foam stability.
Conclusions:
- The dynamic sparge test provides a reliable method for selecting appropriate antifoams for Yarrowia lipolytica fermentation.
- Foam stability and antifoam consumption increase with protein content during fermentation, affecting antifoam efficacy.
- A synthetic fermentation broth model can effectively mimic real fermentation conditions, aiding in antifoam screening and selection.
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