Microbial Metabolism of Food Components ◾ 89
3. A facultative bacterial species is growing anaerobically in the following foods: one rich in
carbohydrates but low in proteins, the second rich in proteins but low in carbohydrates,
and the third rich in both. Also, the carbohydrates and proteins in all three foods can be
metabolized by the bacterial species. Suggest how the bacterial species will metabolize the
two nutrients in these foods.
4. How are the polysaccharides and disaccharides metabolized by microorganisms?
5. List the five major pathways microorganisms use to metabolize monosaccharides found in
foods.
6. List some metabolites produced by Esc. coli and Enterobacter spp. by mixed acid fermentation and Clostridium spp. by butyric acid fermentation.
7. Discuss briefly the significance of microbial metabolism of carbohydrates by aerobic and
anaerobic respiration.
8. How are food proteins metabolized by bacteria? What is the importance of protein synthesis
during growth of microorganisms in food?
9. Discuss the differences and importance of amino acid degradation by microorganisms via
fermentation and aerobic respiration in food.
10. What is the protein sparing effect and how can it be used advantageously in the production
of low-carbohydrate, high-protein foods?
11. List three examples of metabolism of amino acids that can be used for laboratory identification of an unknown bacterial isolate from food.
12. What is the significance of lipid metabolism by microorganisms in food?
References
1. Lengeler, J.W., Drews, G., and Schlegel, H.C., Biology of the Prokaryotes, Blackwell Science, New York,
1999, pp. 59, 110, 163.
2. Gottschalk, G., Bacterial Metabolism, 2nd ed., Academic Press, New York, 1986, pp. 13, 96, 141, 210.
3. Rose, A.H., Chemical Microbiology, Butterworths, London, 1965, pp. 79, 85, 94.
4. Sneath, P.H.A., Ed., Bergey’s Manual of Systemic Bacteriology, Williams & Wilkins, Baltimore, 1986.
5. Gunsalus, I.C. and Stanier, R.Y., Eds., The Bacteria, Vol. II, Academic Press, New York, 1961, pp. 59, 151.
3. A facultative bacterial species is growing anaerobically in the following foods: one rich in
carbohydrates but low in proteins, the second rich in proteins but low in carbohydrates,
and the third rich in both. Also, the carbohydrates and proteins in all three foods can be
metabolized by the bacterial species. Suggest how the bacterial species will metabolize the
two nutrients in these foods.
4. How are the polysaccharides and disaccharides metabolized by microorganisms?
5. List the five major pathways microorganisms use to metabolize monosaccharides found in
foods.
6. List some metabolites produced by Esc. coli and Enterobacter spp. by mixed acid fermentation and Clostridium spp. by butyric acid fermentation.
7. Discuss briefly the significance of microbial metabolism of carbohydrates by aerobic and
anaerobic respiration.
8. How are food proteins metabolized by bacteria? What is the importance of protein synthesis
during growth of microorganisms in food?
9. Discuss the differences and importance of amino acid degradation by microorganisms via
fermentation and aerobic respiration in food.
10. What is the protein sparing effect and how can it be used advantageously in the production
of low-carbohydrate, high-protein foods?
11. List three examples of metabolism of amino acids that can be used for laboratory identification of an unknown bacterial isolate from food.
12. What is the significance of lipid metabolism by microorganisms in food?
References
1. Lengeler, J.W., Drews, G., and Schlegel, H.C., Biology of the Prokaryotes, Blackwell Science, New York,
1999, pp. 59, 110, 163.
2. Gottschalk, G., Bacterial Metabolism, 2nd ed., Academic Press, New York, 1986, pp. 13, 96, 141, 210.
3. Rose, A.H., Chemical Microbiology, Butterworths, London, 1965, pp. 79, 85, 94.
4. Sneath, P.H.A., Ed., Bergey’s Manual of Systemic Bacteriology, Williams & Wilkins, Baltimore, 1986.
5. Gunsalus, I.C. and Stanier, R.Y., Eds., The Bacteria, Vol. II, Academic Press, New York, 1961, pp. 59, 151.