Notes

Causes of Contamination
There are three causes of contamination:

chemical – caused by the presence of chemicals in food, such as pesticides, insecticides and cleaning agents

biological – contracted by eating plants containing natural poisons, including poisonous species of mushrooms. Another form of biological food poisoning is called microbial food poisoning – this is caused by microorganisms such as viruses, moulds and bacteria. Micro-organisms are small, usually single-celled organisms that cannot be seen by the naked eye. Most micro-organisms cause no harm, but some cause food spoilage (visible contamination). Some micro-organisms cause food poisoning (invisible contamination).

physical – caused by harmful substances (such as glass fragments or metal shavings) that are introduced during the preparation process.

Conditions that may lead to food spoilage and contamination
It is important to be aware of the different types of food safety hazards which may pose a significant risk to the safety of your customers. Situations when food safety hazards are likely to pose a significant risk are:

handling "potentially hazardous foods" which are susceptible to microorganisms, contamination and growth.
handling raw food and fresh foods
using your hands rather than tongs or spatulas
under-cooking food
defrosting food- should never be done at room temperature
reheating foods- above 65 degrees
displaying food on buffets or self service
preparing food in the danger zone


Bacteria are living organisms that require certain conditions to grow including:

moisture
temperature between 5-60 degrees
PH neutral-acidic
oxygen