applied micro Flashcards
Give two reasons for preventing microbes from getting into food.
prevent food related illness
prevent food spoilage
How could microbes contaminate food?
food can get contaminated with
- with soil
- handling- when you bought a sandwich did they handle and make it properyl
- harvesting/slaughtering- when we get meat, they have to cut animal to expel gut properly to avoid contamination
- improper storage
- preparation procedures
How does fermentation preserve food?
Lactic acid bacteria grow, produces lactic acid, lowers the pH, other bacteria isn’t able to grow
List two of each pathogenic bacteria viruses and parasites that can cause illness through food or water?
Bacteria: Bacillus cereus (rice), Staphylococcus aureus (ham), Campylobacter (chicken)
Virus: Norovirus (seafood), Rotavirus
Parasite: Helminth-Nematode (round worm), Giardia lamblia (food)
Why does spoilage of food appear rapid when the microbes are on the food for long periods before the appearance of spoilage?
It is due to exponential growth pattern microbes, initial population is mixed, microbe with the shortest generation time under the conditions of storage will dominate.
List two uses for microbes in industry
Fermentation - preserves food
Dairy Products - cheese and sour cream
List two reasons for treating waste water
Removes pathogens, removes toxins and prevents contamination of drinking water.
Prevents foul odours and removes nutrients that cause pollution.
What is B.O.D?
Biochemical oxygen demand
What does BOD indicate?
Measures the decrease in oxygen concentrations following the oxygen dependent oxidation of organic compounds by bacteria
What is the main process in secondary sewage treatment?
Hydrolysis - Reaction where complex macromolecules are split into smaller parts by reacting with H2O
Give 3 uses for Bacteriophage
Possible treatment for bacterial infection
Identify pathogenic bacteria
Recombinant DNA technology
What are the advantages of using HIV as a vector for gene therapy?
Retrovirus, reverse transcriptase generates DS-DNA, Integrated into host chromosome, gene replacement therapy, deliver and express gene
