Fermentation

Fermentation technology can be used to produce valuable biological compounds in large quantities. For instance, most antibiotics are produced using fermentation technology. Desired compounds used in most antibiotics are produced in large tanks, in which fungi grows. To ensure quality production, fungi are grown under specific conditions to promote production of the desired compound. Fermentation can be used to produce pharmaceuticals, bioethanol, biochemicals, enzymes and many other products. Ensuring that cells have optimal conditions for production is not a trivial task. Many theories, mathematical models, and advanced laboratory and production equipment have been developed to allow and increase production.

In this lab, students will setup fermentation of a second-generation bioethanol production plant that converts waste into bioethanol. Students make a pilot scale experiment and develop a process for efficient bioethanol production. By the end of the lab, students will have a thorough understanding of Fermentation Technology and its application.

Yeast inoculum and aseptic technique

Students begins by preparing a yeast inoculum using the aseptic technique. Students practice the aseptic technique by using the Bunsen burner and making sure the media has been autoclaved in order to minimize risk of contamination. After students successfully acquire a pure yeast inoculum, they perform analysis on a small sample under microscope observation. The lab stresses the importance of acquiring a pure yeast inoculum in order to get the highest bioethanol production. After acquiring a pure inoculum, students preform the first fermentation. Learning about the fermenter and how it operates, students learn how to ensure yeast mono cultivation.

Mathematical simulation and data analysis

Using mathematical simulation, students can change various fermentation parameters. This includes temperature, pH, stirring power, and selection between air and nitrogen. A graph will be plotted based on the selected parameters. Furthermore, a spreadsheet containing time, biomass, glucose, ethanol, oxygen and carbon dioxide amounts reflecting the specific parameters is shown. Students must then analyze the output data and create a plot that shows the optimum temperature and pH for producing bioethanol.

A short guide on how to use Excel is provided for student access by clicking the “View Theory” button.

Using the downloaded data, students will perform calculations of the many outcomes including the specific growth rate of the different phases, doubling time and yield coefficient. A comparison between fermentation that is performed using 21% oxygen or no oxygen (in this case 100% nitrogen) is also done.

After completing the fermentation lab, Student will have a deeper understanding on production of bioethanol, common lab procedure, experiment design and analysis and organization of output data.