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Updated: Jul 4, 2026
04:41
Measuring Lactase Enzymatic Activity in the Teaching Lab
Published on: August 6, 2018
Kinetics of whey-lactose acidogenesis
W S Kissalita1, K V Lo, K L Pinder
1Department of Bio-Resource Engineering, University of British Columbia, Vancouver, British Columbia, Canada V6T 1W5.
Biotechnology and Bioengineering
|January 25, 1989
Summary
This study explores anaerobic fermentation of lactose into organic acids using a continuous-flow stirred-tank fermentor. Microbial growth and pH are modeled to understand end-product distribution during this bioconversion process.
Area of Science:
- Biotechnology
- Microbial Metabolism
- Chemical Engineering
Background:
- Lactose fermentation is a key bioprocess for producing organic acids.
- Understanding microbial growth dynamics is crucial for optimizing fermentation.
- Continuous-flow stirred-tank fermentors offer advantages for industrial-scale bioconversions.
Purpose of the Study:
- To investigate the mixed-culture anaerobic conversion of lactose to organic acids.
- To analyze the distribution of acidogenic end-products based on dilution rate.
- To model microbial growth and its impact on pH during fermentation.
Main Methods:
- Utilized a bench-scale continuous-flow stirred-tank fermentor.
- Employed a Monod chemostat model to describe microbial growth kinetics.
- Analyzed end-product distribution in relation to varying dilution rates.
Main Results:
- Presented the major acidogenic end-product distribution as a function of dilution rate.
- Estimated key parameters of the Monod chemostat model.
- Discussed the influence of these parameters on the fermentation's pH.
Conclusions:
- The study provides insights into the anaerobic conversion of lactose to organic acids.
- The Monod chemostat model effectively describes microbial growth and influences pH.
- Findings are relevant for optimizing bioprocesses involving lactose fermentation.
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