Food contamination refers to the presence of harmful chemicals and microorganisms in food which can cause consumer illness.
A food contaminant has been defined as any substance not intentionally added to food, which is present in such food as a result of the production, manufacture, processing, preparation, treatment, packing, transport or storage of such food as a result of environmental contamination.
It is important to protect food from risk of contamination to prevent food poisoning and the entry of foreign objects.
There are three main ways in which food can become contaminated:
(i) Microbial Contamination
(ii) Physical Contamination
(iii) Chemical Contamination
Info Source: Introduction to Food and Food Processing Book