Lecture 5: Pathogenic bacteria, Shigella and Bacillus cereus

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A.Food Safety and H.A.C.C.P.2.Pathogenic
microorganisms and foods
5. Pathogenic bacteria Shigella, Bacillus cereus
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Shigella

• it is a mesophilic, facultative anaerobic,
  rod-shaped bacterium
• it causes gastroenteritis
• it can be found in milk and dairy products, water
  and poultry

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Shigella through a microscope
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Shigella and Shigellosis
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Shigellosis
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Bacillus cereus

• it is a spore-forming, rod-shaped bacterium
• it produces toxins
• it can be found in plant foods (rice, potatoes,
  pasta, corn)

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Bacillus cereus through a microscope
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Contamination with Bacillus cereus
The spores of Bacillus cereus are found in rice,
spices, corn flower. Spores are not destroyed
during cooking
The food remains in   danger zone (5-60 C)
for several hours
The food is cooled slowly and then reheated
Bacillus cereus food poisoning may occur
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Bacillus cereus and food poisoning
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Summary of 5th Lecture

• Shigella
• Bacillus cereus