1. Applied and Industrial Microbiology
Chapter 28
Applied and Industrial Microbiology

2. Q&A
To produce ethanol, yeasts require anaerobic conditions. In what widely used industrial product does the growth of Saccharomyces cerevisiae require aerobic conditions?

3. Food Microbiology
28-1 Describe thermophilic anaerobic spoilage and flat sour spoilage by mesophilic bacteria.
28-2 Compare and contrast food preservation by industrial food canning, aseptic packaging, radiation, and high pressure.
28-3 Name four beneficial activities of microorganisms.

4. Historically…
Drying
Osmotic pressure (salt or sugar)
Fermentation

5. Foods and Disease Hazard Analysis and Critical Control Point (HACCP)
FDA
USDA

6. Industrial Food Canning
Figure 28.1

7. Commercial Canning Retorts
Figure 28.2

8. Construction of a Metal Can
Figure 28.3

9. Commercial Sterilization
Destroys C. botulinum endospores
12D treatment kills 1012 endospores
Surviving endospores of thermophilic anaerobic spoilage with gas
Or flat sour spoilage

10. Food Preservation
Aseptic packaging: Presterilized materials assembled into packages and aseptically filled
Figure 28.4

11. Ionizing Radiation
Figure 28.5, Table 28.2

12. Food Preservation High-energy electrons High-pressure: 87,000 psi
Figure 28.7

13. Cheese Curd: Solid casein from lactic acid bacteria and rennin
Whey: Liquid separated from curd
Hard cheeses are produced by lactic acid bacteria
Semisoft cheeses are ripened by Penicillium on surface

14. Making Cheddar Cheese
Figure 28.8

15. Making Red Wine
Figure 28.9

16. Alcoholic Beverages and Vinegar
Beer and ale are fermented starch
Malting: Germinating barley converts starch to maltose and glucose
For sake, rice starch is converted to sugar by Aspergillus
Wine is fermented plant sugars
Yeast ferment sugars to ethanol + CO2
Grape wine requires bacterial malolactic fermentation
Acetobacter and Gluconobacter convert ethanol to acetic acid

17. Microbial Metabolism Sugar Ethanol + CO2 Malic acid Lactic acid
Saccharomyces cerevisiae
Malic acid
Lactic acid
Lactic acid bacteria
Ethanol
Acetic acid
Acetobacter or Gluconobacter

18. Q&A
To produce ethanol, yeasts require anaerobic conditions. In what widely used industrial product does the growth of Saccharomyces cerevisiae require aerobic conditions?

19. Is botulism a greater danger in spoilage of canned goods under thermophilic or under mesophilic conditions? 28-1
Canned foods are usually in metal cans. What sorts of containers are used for aseptically packaged foods? 28-2
Roquefort and blue cheeses are characterized by blue-green clumps. What are these? 28-3

20. Industrial Microbiology
28-4 Define industrial fermentation and bioreactor.
28-5 Differentiate primary from secondary metabolites.
28-6 Describe the role of microorganisms in the production of industrial chemicals and pharmaceuticals.
28-7 Define bioconversion, and list its advantages.
28-8 List biofuels that can be made by microorganisms.

21. Biotechnology
Use of microorganisms, cells, or cell components to make a product
Classical: Fermentation
Recombinant DNA

22. Fermentation Technology
Figure 28.10a

23. Fermentation Technology
Figure 28.10b

24. Production Curve of a Primary Metabolite
Figure 28.11a

25. Production Curve of Secondary Metabolite
Figure 28.11b

26. Immobilized Cells
Figure 28.12

27. Industrial Products Xanthan Amino acids Citric acid Enzymes Vitamins
Antibiotics
Steroids
Applications, p. 801

28. Copper Extraction by Leaching
Figure 28.14

29. Alternative Energy Sources Using Microbes
Bioconversion
Biomass
Methane or ethanol
Figure 28.15

30. Biofuels Cellulose digested by cellulase
Sugars fermented to ethanol or higher alcohols or hydrogen
Algal oils
Figure 28.16

31. Industrial Microbiology and the Future
Food processing
Pharmaceuticals from rDNA technology
Ethanol and hydrogen
And more

32. Are bioreactors designed to operate aerobically or anaerobically? 28-4
Penicillin is produced in its greatest quantities during the trophophase of fermentation. Does that make it a primary or secondary metabolite? 28-5
At one time, citric acid was extracted on an industrial scale from lemons and other citrus fruits. What organism is used to produce it today? 28-6
Landfills are the site of a major form of bioconversion—what is the product? 28-7
How can microbes provide fuels for cars and electricity? 28-8