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What causes food contamination?

Food contamination


Food contamination occurs when something is found in food that shouldn’t be there. Contaminated food can be unsafe for consumption.

Causes of food contamination

There are three ways that food can be contaminated:

  • biological hazards (microorganisms)
    including bacteria, fungi, yeasts, mould and viruses
  • chemical hazards
    including cleaning chemicals or foods with naturally occurring toxins, such as green potatoes
  • physical hazards
    including dangerous physical objects such as plastic, glass, elastic bands, wood chips or bandages.

Beware! Selling contaminated food could lead to customer illness or injury, legal action taken by the local council and the customer, bad publicity including the closure of the premises or loss of your job.

You must follow the correct food handling techniques to ensure that food is not contaminated.

Where do bacteria come from?

Food poisoning is most often caused by bacteria that have been able to multiply or form a toxin in the food.

Bacteria and other microorganisms can be found in soil, on animals, on people and on the things people touch and use.
One of the greatest threats to food safety is the fact that bacteria can multiply from just a few cells to millions in a very short period of time.

Some of the factors that affect the growth of bacteria include:

  • the temperature of food
  • the moisture content of food
  • the time they have to grow in food, particularly food kept in the danger zone of 5 °C to 60 °C.
  • exposure to air.

Bacteria will not grow quickly if these factors are controlled.

Answer this question...

Finding a piece of plastic in food is which type of contamination?

Incorrect! Why is this?

Correct! Why is this?

You have the right to reject the delivery if you find the food unsafe

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