Lecture 4: Pathogenic bacteria, Listeria monocytogenes and Salmonella

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A.Food Safety and H.A.C.C.P.2.Pathogenic
microorganisms and foods
4. Pathogenic bacteria Listeria monocytogenes
and Salmonella
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Listeria monocytogenes

• it is a rod-shaped,  psychrotrophic  bacterium
•  it causes listeriosis (fatal disease)
• it can be found in raw dairy products, soft
  cheeses, ice cream, fresh vegetables, poultry and
  fish

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Listeria monocytogenesthrough a microscope
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Listeria monocytogenes and food poisoning
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Salmonella

• it is a rod-shaped, mesophilic, facultative,
  anaerobic bacterium
• it causes gastroenteritis
• it can be found in poultry, eggs, raw meat,
  insects and excrement

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Salmonella through a microscope
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Contamination with Salmonella stage I
feed contaminated with Salmonella
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Contamination with Salmonella stage II
transmission to animals
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Contamination with Salmonellastage III
growth and expansion of Salmonella
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Contamination with Salmonellastage IV
modes of transmission
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Contamination with Salmonellastage V
Cross contamination in the kitchen
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Contamination with Salmonellastage VI
food remains in the danger zone (5 to 60 0C)
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Salmonella food poisoning
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Summary of 4th Lecture

• Listeria monocytogenes
• Salmonella