FOOD POISONING

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FOOD POISONING
(c) PDST Home Economics
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FOOD POISONING

• Food poisoning is caused by eating food
  containing harmful substances.
• There are 3 types of food poisoning
• Chemical food poisoning caused by chemicals such
  as antibiotics or pesticides in the food.
• Biological food poisoning caused by chemicals
  that occur naturally in the food e.g. solanine in
  green potatoes or toxins in red kidney beans.
• Bacterial food poisoning caused by the presence
  of pathogenic bacteria in the food.

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SYMPTOMS OF FOOD POISONING

• Nausea
• Vomiting
• Abdominal cramps
• Diarrhoea
• Fever
• Headache
• Loss of appetite
• Very serious for infants, invalids, pregnant
  women and elderly.

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(H) BACTERIAL FOOD POISONING

• There are 2 types of bacterial food poisoning
• 1. Toxic food poisoning
• 2. Infectious food poisoning

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(H) 1. TOXIC FOOD POISONING

• Some bacteria produce exotoxins as they grow in
  food both before and after its eaten.
• Exotoxins are hard to destroy. Boiling for 30
  mins is required.
• Symptoms develop quickly- often within 2 hours
• Examples staphylococci and clostridium botulinum

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(H) 2. INFECTIOUS FOOD POISONING

• Caused by eating food containing large numbers of
  live pathogenic bacteria.
• These bacteria make endotoxins which are released
  when they die.
• Endotoxins are easy to destroy. Proper cooking
  and reheating will destroy both toxins and
  bacteria.
• If not destroyed symptoms will appear after
  approx. 12 hours
• Salmonella and listeria cause infectious food
  poisoning.

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(H) HIGH RISK FOODS

• Liquid protein foods are at high risk of
  contamination
• Milk, cream
• Eggs egg dishes e.g. custard, mayonnaise
• Meat, poultry, fish, shellfish
• Meat pies, gravies, sauces, soups and stock
• Reheated dishes

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(H) FOOD POISONING BACTERIA

• Learn 3 common strains of food poisoning
  bacteria e.g.
• Salmonella, Staphylococcus aureus, Listeria
  monocytogenes.
• Habitat /Sources
• Factors affecting growth
• High risk foods
• Incubation period
• Toxic or infectious
• Symptoms

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OTHER FOOD WATER BORNE DISEASES

• Here the food acts only as a means of transport
  for the organism. They do not grow in it.
• Incubation longer.
• Only small number of organisms can cause illness.
• Organism enters bloodstream.
• Symptoms varied - may not include vomiting or
  diarrhoea.