What is contamination of food?

Contamination of food is the transference of any objectionable, harmful substance or material to food.

There are four types of contamination


Microbiological Contamination

Caused by bacteria, toxins, moulds, viruses (micro-organisms) or parasites.

Control methods include-

  • High standards of personal hygiene e.g thorough & regular handwashing
  • On-going staff training, knowledge and enforcement of policies & procedures



Chemical Contamination

from pesticides, residues from cleaning chemicals, veterinary drugs, perfume, scented soap and machine oils.

Control methods include –

  • Safe and correct storage of chemicals
  • On-going staff training, knowledge and enforcement of policies & procedures
  • Suitable protective clothing and equipment – colour coded


Physical Contamination

from foreign bodies, including insects e.g packaging materials, machinery and equipment, glass, plastic, string. Rodents hair and droppings.

Control methods include-

  • Pest control policy, procedure and enforcement
  • Metal detectors
  • Start/end production checks


Allergenic Contamination

The main cause of this is cross contamination from allergenic to non-allergenic products.

Control methods include-

  • All food handlers should be trained in allergen awareness and the effects of ingesting allergens by the consumer
  • Dedicated areas, colour coded equipment for allergen production only
  • Thorough and effective cleaning procedures that are regular monitored and corrected.