Overview
This lecture introduces fermentation (anaerobic respiration) in yeast, focusing on its applications in alcohol production, biofuels, and bread making.
Fermentation in Yeast
- Fermentation is anaerobic respiration in yeast, meaning it occurs in the absence of oxygen.
- The summary equation for yeast fermentation is: glucose → ethanol + carbon dioxide.
- Yeast is a microorganism capable of both aerobic and anaerobic respiration.
- Under anaerobic conditions, yeast produces ethanol (alcohol) and carbon dioxide.
Uses of Fermentation
- Ethanol produced by fermentation can be used to make alcoholic beverages such as beer.
- Ethanol can also serve as a biofuel, a renewable energy source.
- Carbon dioxide produced during fermentation is used in bread making.
- Carbon dioxide forms bubbles in the dough, causing it to rise and improving the bread's texture.
Bread Making and Fermentation
- Yeast in bread dough ferments, releasing carbon dioxide that helps the dough rise.
- Ethanol is also produced in the dough but evaporates during baking.
Key Terms and Definitions
- Fermentation — an anaerobic respiration process where microorganisms like yeast convert glucose into ethanol and carbon dioxide.
- Anaerobic respiration — respiration occurring without oxygen.
- Yeast — a microorganism capable of both aerobic and anaerobic respiration.
- Ethanol — an alcohol produced during fermentation, used in beverages and biofuels.
- Biofuel — fuel derived from biological sources, such as ethanol produced by fermentation.
Action Items / Next Steps
- Review the summary equation for yeast fermentation.
- Understand the practical applications of fermentation (alcohol, biofuels, bread making).