Cross contamination can come from a number of sources and cause harm. Glass, raw food, insects, people, clothing, chemicals and rodents are just a few.
The types are foreign bodies, chemical, allergens and microbiological.
Foreign bodies or physical contaminants can generally be seen with the human eye. They may cause injury or be distasteful, but not harmful. Common methods of controlling foreign bodies are to have materials such as wood and glass banned from production kitchens. Another method of controlling these is to have coloured materials such as blue plastics. Find out more about foreign bodies by clicking the button or here.
Chemical cross contamination
Contamination from chemicals can happen for a number of reasons. For example, when cleaning chemicals are used at the wrong dilution, or in the wrong place. Another example is from poor working practices, such as not washing hands after using chemicals. They may come from environmental sources such as pollution. Some of these a food business operator has direct control over. Others, such as pollution, they do not. However, the choice of supplier is always available. A trusted and approved supply chain will check for cross contamination sources such as pollution.
Microbiological cross contamination
Bacteria, viruses, moulds and yeasts as well as protozoa can all cause disease, or be pathogenic. Some of these produce toxins or poisons which may make the consumer ill, or even kill them. The contamination may happen from raw to cooked or ready to eat food. Vectors can include people, pets, pests or equipment used for raw then ready to eat food.
In the UK, the Food Standards Agency has detailed guidance about the information required for the consumer, here. There are 14 foods which contain allergens that are listed in the legislation. However, people are allergic to more than these 14. When preparing food to serve direct to the consumer, reading the label is essential. When manufacturing food, the specifications will have all the necessary information in. Contamination can happen when poor equipment cleaning or separation of allergenic and non allergenic foods occurs. Sometime food allergens can be in unusual places, such as cleaning chemicals. Recalls for allergens are frequent. These are often due to missing allergen declarations as happened to Alana from The Apprentice