1. Good Microbes Fermentation Process

2. Goal of Metabolism Utilize food (sugars) in order to store energy in the form of ATP. Differences between prokaryotes and eukaryotes. Utilize food (sugars) in order to store energy in the form of ATP. Differences between prokaryotes and eukaryotes. Therefore, the production of alcohol, rising bread, souring of milk (yogurt and cheese) are bi-products of organisms attempting to make ATP. Therefore, the production of alcohol, rising bread, souring of milk (yogurt and cheese) are bi-products of organisms attempting to make ATP.

4. Metabolism with Oxygen

5. Yeast Metabolism in Wine Making C6H12O6 ====> 2(CH3CH2OH) + 2(CO2) Sugar ====> Alcohol + Carbon dioxide gas (Glucose) (Ethyl alcohol) C6H12O6 ====> 2(CH3CH2OH) + 2(CO2) Sugar ====> Alcohol + Carbon dioxide gas (Glucose) (Ethyl alcohol) Yeast metabolism often begins as an aerobic condition in which the yeast multiply rapidly, then switches to an anaerobic condition in which the fermentation process takes place. Yeast metabolism often begins as an aerobic condition in which the yeast multiply rapidly, then switches to an anaerobic condition in which the fermentation process takes place.

8. Summary In the anaerobic condition, yeast will yield only 2 ATP’s per molecule of glucose, plus ethanol and CO2. In the anaerobic condition, yeast will yield only 2 ATP’s per molecule of glucose, plus ethanol and CO2. While this works for good wine, the level of ethanol soon becomes too concentrated and actually kills the yeast that produced it. While this works for good wine, the level of ethanol soon becomes too concentrated and actually kills the yeast that produced it. Therefore, yeast are considered falcultative anaerobes. Therefore, yeast are considered falcultative anaerobes.

9. Wine Making Wine is usually made from grapes because it has the right balance of natural sugars, nutrients and pH for the yeast to work. Wine is usually made from grapes because it has the right balance of natural sugars, nutrients and pH for the yeast to work. Yeast converts the sugars to alcohol and CO2, we let the CO2 dissipate before bottling. Yeast converts the sugars to alcohol and CO2, we let the CO2 dissipate before bottling. Yeast dies after sugar is gone (or alcohol content kills them) Yeast dies after sugar is gone (or alcohol content kills them) Specialized yeasts (wine yeasts) are able to withstand higher levels of ethanol than bread yeasts. Specialized yeasts (wine yeasts) are able to withstand higher levels of ethanol than bread yeasts.

10. ATP Yield Without Oxygen

11. ATP Yield With Oxygen

12. Prokaryotic Metabolism Can use alcohol fermentation pathway or lactate (lactic acid fermentation pathway). Can use alcohol fermentation pathway or lactate (lactic acid fermentation pathway). In cheese making, we used the lactic acid pathway using bacteria Lactobacillus. In cheese making, we used the lactic acid pathway using bacteria Lactobacillus. First, proteins in milk are transformed into solid lumps called curds. Second, the curds are separated from the milky liquid, called whey, and shaped or pressed into molds. Finally, the shaped curds are ripened using a variety of different aging and curing techniques. First, proteins in milk are transformed into solid lumps called curds. Second, the curds are separated from the milky liquid, called whey, and shaped or pressed into molds. Finally, the shaped curds are ripened using a variety of different aging and curing techniques.

14. Your Job What is happening with rising bread? Which pathway and what happens to all these products? What is happening with rising bread? Which pathway and what happens to all these products? What other foods do we make or utilize using microbes? What other foods do we make or utilize using microbes?