Page 13 - Comprehensive Food Safety

31.03.2020

BIOLOGICAL HAZARDS

Micro-organisms or microbes (bugs) are very small living organisms that can only be seen under
powerful microscopes and include bacteria, viruses, yeasts and moulds. Other biological
hazards include allergens, parasites and toxic algae bloom. Bacteria, yeasts and moulds can
cause food spoilage if bacteria are allowed to grow to dangerous levels, or yeasts and moulds
allowed to develop in food by keeping it past its expiry date, or storing it in the wrong
conditions.

What signs would you see that would show that the food was spoiled?

• slime, mould, smell, change of colour (grey/green meat) and gas, for example fizzy
orange juice, the bottle/container will look ‘blown up’.

BACTERIA

Bacteria are microscopic forms of life and we cannot escape them. They are all around us, in
and on the bodies of animals and humans, in soil, air, water and most other matter found on
earth. There are lots of different types of bacteria; however, the food handler’s responsibility is
to concern themselves with spoilage bacteria and pathogenic bacteria. The poisonous waste
product of some bacteria is called a toxin. Some bacteria produce thick-walled protective
structures called spores inside their cells. They can often survive cooking, freezing and
sanitizing mixtures.

Spoilage bacteria: are bacteria that make the food go off – rot, spoil or decay. They are a real
nuisance as they are responsible for the loss and destruction of tonnes of food each year.
However, most spoilage bacteria do not make people ill and do not cause food poisoning. The
food is spoilt by the micro-organisms that are naturally found in the food – spoiling the food.

Pathogenic bacteria: are bacteria that cause disease. Pathogenic bacteria are responsible for
most cases of both food poisoning and food-borne illness. Only a few, of all the thousands of
types of bacteria, are the cause of illness. Small numbers of pathogenic bacteria can be eaten
without causing any side effects - it is large quantities being present in the food consumed that
generally causes illness.

In order to grow to dangerous levels bacteria needs:

• time (more than 4 hours),
o
o
• the right temperature (5 c to 60 c),
• moisture,
• the right pH levels (over 4.6),
• food (such as poultry, meat, seafood, dairy products)
• and some (not all) require oxygen.

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