Microbiology

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Microbiology

• The study of Microorganisms
• Gail Wagley (Roses mom)

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Microorganisms

• Most are microscopic (cant be seen without a
  microscope)
• Include
• Viruses (eg. cold viruses, the flu, stomach
  viruses, and food-borne Norovirus, Hepatitis)
• Bacteria (Salmonella, E. coli, Staphylococcus
  (staph), Listeria)
• Parasites

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Bacteria

• Bacteria can multiply from 1 to 100,000,000 cells
  overnight!!!
• One cell can grow overnight on an agar plate to
  become a pin-point sized colony of a million
  cells that you can see
• Beneficial (decomposers, digestive bacteria,
  penicillin producers)
• Harmful (pathogens cause human or animal
  illness)

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Food Microbiology (my job)

• Testing Food and Make-up for pathogens
  (disease-causing bacteria)
• Common Pathogens we recover
• Salmonella (fruits, vegetables, flour, eggs (only
  one type), raw or undercooked fish, raw or
  undercooked chicken) commonly carried by birds
  and reptiles
• E. coli (fruits, vegetables, cheese, raw or
  undercooked meat) carried by mammals (deer, pigs,
  cows, humans)
• Listeria (vegetables, fruits, milk, cheese, other
  processed foods) common in soil

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Keeping Food Safe

• Wash fruits and vegetables (dirt and animal
  contamination)
• Completely cook meat
• Wash hands and utensils after handling raw meat
• Refrigerate Foods!
• Dont leave cooked food out too long

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How do we find bacteria in food?

• Add food to liquid that contains all the things
  bacteria love (let it grow!!)
• Add that to another media (agar, liquid) that
  contains something other bacteria dont like or
  cant eat
• Add that to another media that changes color with
  the bacteria you are looking for so you can
  recognize it

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Salmonella
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E. coli

• Some E. coli can make you very sick
• Some E. coli is beneficial
• Any E. coli in food is a sign of poor hygiene of
  food-handlers or improper cooking of raw meat

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Listeria

• Can cause sickness in humans (especially old and
  pregnant people)
• If found in food, can be a sign of dirty
  environment and poor food preparation practices

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