1. Biotechnology – Use of Microbes
Kitchen Microbiology
Biotechnology – Use of Microbes

2. Your understanding of Microbes
What is a microbe?
Where do you find them?
Are they beneficial or harmful?

3. Microbes in the Kitchen
Microbes or MO (microorganisms) are a part of our everyday life.
What did you eat yesterday? List them in your notebook.
Let see if any of your food is made by our tiny friends (MOs).

4. Commonly Known
Cheese/Butter – Fermentation lowers the pH, thus helping in the initial coagulation of the milk protein, as well as giving characteristic flavors. Some of the bacteria used in cheese fermentation is found in smelly feet (Streptococcus and Lactobacillus bacteria)
Bread - provides a variety of enzymes that enable carbohydrates to be broken down producing sufficient carbon dioxide to give bread its characteristic texture. (Baker’s Yeast - Saccharomyces cerevisiae)
Beer -Traditionally, the natural yeasts on grape skins determine the quality of wine produced. These natural yeasts, especially Saccharomyces cerevisiae (beer in Spanish is "cervesa") and Saccharomyces ellipsoideus, ferment the grapes to make wine.

5. Coffee/ Cocoa (chocolate)
Bacteria and yeast are used to remove the outer coats of coffee.
Erwinia dissolvens, leuconostoc, and lactobacillus species, Saccharomyces
The microbes do not affect the taste of coffee but are necessary to confer the characteristic taste to cocoa and chocolate.

6. Soy sauce/Vinegar
Soy sauce/Miso - made from a mixture of soy beans and rice fermented by a variety of bacteria and fungi.
Lactobacillus delbrueckii, Aspergillus oryzae, Aspergillus soyae, and Saccharomyces rouxii.
Vinegar - Vinegar is made by two distinct biological processes, both the result of the action of harmless microorganisms (yeast and “Acetobacter”) that turn sugars (carbohydrates) into acetic acid.
The first process is called alcoholic fermentation and occurs when yeasts change natural sugars to alcohol under controlled conditions. In the second process, a group of bacteria (called “Acetobacter”) converts the alcohol portion to acid.

7. Vitamins/MSG
Microbes may be used to elaborate precursors in the making of Vitamins A, C, and the B family. Using sugarbeet molasses as a growth medium, Pseudomonas denitrificans is made to produce Vitamin B12. Members of the genus Propionibacterium are also used to make this vitamin. Although many bacteria and fungi produce riboflavin (B2), the fungus Ashbya gossypii produces it in huge quantities.
MSG (monosodium glutamate) is manufactured by Corynebacterium glutamicum, a cousin of the diptheria germ.
The fungus, Aspergillus niger, when grown on sugarbeet molasses, produces huge quantities of citric acid.

8. Amino Acids
Citric acid used to be extracted primarily from lemons, but worldwide demand for it forced the commercial industry to seek other sources. The fungus, Aspergillus niger, when grown on sugarbeet molasses, produces huge quantities of citric acid.
Glutamic acid requires Corynebacterium glutamicum for its formation. Biotin is a cofactor essential for lipid synthesis in bacteria. By growing C. glutamicum on limited amounts of biotin, it causes the bacterial membrane to leak sufficient quantities of glutamic acid.
Lysine -- The bacterium, Brevibacterium flavum is used in the industrial biosynthesis of lysine. Mutants no longer susceptible to feedback inhibition have been isolated to be used industrially to increase the yield of amino acids.

9. Meat Products
Meat products, like salami and bologna sausages, require some fermentation with Pediuococcus cerevisiae, Lactobacillus plantarum and some members of the genus Bacillus. Country cured hams use fungi of the genus Aspergillus and the genus Penicillium in their fermentation process. Izushi (sushi), a Japanese delicacy made from a mixture of fish, rice, and other vegetables is produced by fermentation with lactobacilli.

10. Pickled Food
Dill pickles are simply fermented cucumbers. Streptococci starts the process of fermentation, but as the pH level falls, leuconostoc and pediococcus species, as well as Lactobacillus plantarum continue the process.
Olives are edible only after fermentation with Lactobacillus plantarum and Lactobacillus mesenteroides.

11. Homework Find one thing at home that is made by microorganism.
On a puzzle piece
Front: place a picture of the product, write the name of the MO and the ingredient produced by the MO.
Back: your name, period, and date