Chapter 5

  1. What is sterilization?
    • Complete removal of microbes
    • Uses heat, filtration, chemicals, irradiation
  2. What is Disinfection?
    • Eliminates most pathogens
    • Uses: Disinfectants/Antiseptics
  3. What is pasteurization?
    Heat treatment that reduces number of microbes in food and drink.
  4. What is decontamination?
    Reduce pathogens to levels considered safe
  5. What is degerming/demicrobing?
    • Decrease number of microbes in a area
    • used especially on skin
  6. What is sanitization?
    Substantially reduced microbial population
  7. What is preservation?
    Process used to delay spoilage
  8. Best way to control microbes in daily life?
  9. Best way to control microbes in hospitals?
  10. What is a nasocomial infection?`
    Infection caught in a hospital
  11. What does selection of microbial removal procedure depend on?
    • Type of microbe
    • Type of environment
    • Risk of infection
    • Composition of infected item
  12. What is a critical item?
    Comes in contact with body tissues
  13. What is a semi-critical item?
    Contacts mucous membranes but does not penetrate skin.
  14. What is a non-critical item?
    Contacts unbroken skin only.
  15. How can heat be used to control microbial growth?
    • Used to sterilize or disinfect
    • Moist or dry heat
  16. How does moist heat destroy microbes and what are the 3 methods?
    • Coagulation
    • Boiling
    • Pasteurization
    • Pressurized Steam
  17. What is an autoclave?
    Sterilizes items using pressureized steam.
  18. When is filtration used in microbial control?
    • Used to remove microbes from air
    • Used to remove microbes from fluids that can't be boiled
  19. How and when is radiation used to control microbial growth?
    • Gamma radiation
    • X-rays
    • Electron Accelerators
    • Used on heat resistant materials
  20. What chemicals are used to control microbial growth?
    • Alcohol - used in disinfectants and antiseptics
    • Ozone - used in drinking and waste water
    • Hydrogen Peroxide - useful as a disinfectant
    • Phenolics - Lysol ingredient
    • Chlorine - Pools
  21. What are some chemical preservatives?
    • Ascorbic, Benzoic and Propionic acids - used in bread, cheese, juice
    • Nitrates, Nitrites - used in processed meats
  22. How does freezing control microbial growth in food?
    • Kills 50% of microbes
    • Irreversibly damages cells
Card Set
Chapter 5
Microbiology: A human perspective - chapter 5