Avoiding Cross-Contamination
Cross-contamination in food is one of the common causes of foodborne illness. Micro-organisms originated from many sources can contaminate food including safely cooked, ready-to-eat food during the food preparation and storage processes. Preventing cross-contamination can help to eliminate the incidence of foodborne illness.
1. What is cross-contamination in food?
It refers to the transfer of harmful bacteria from a source to food products either by direct or indirect contact.
2. How does cross-contamination in food occur?
The common routes of cross-contamination are:
Food to Food
Raw perishable food can contain harmful bacteria. For instance, raw meats contain a large number of naturally occurring bacteria such as Salmonella, Listeria and Campylobacter, which cause foodborne illness. Hence, harmful bacteria can be transferred from raw to cooked or ready-to-eat food.
For example:
Meat drippings from raw meat placed on the top shelf of the refrigerator may drip onto ready-to-eat food that is placed on a lower shelf.
Placing improperly packed raw food next to ready-to-eat or cooked food in the refrigerator.
Equipment to Food
Bacteria are able to multiply in cracks and crevices found in equipment. If kitchen equipment and utensils are improperly cleaned, the bacteria can be transferred to another food. For example:
Use of the same knife and cutting board for cutting different types of food such as raw food, followed by ready-to-eat food (e.g. salads) without thorough washing of the knife and cutting boards.
Work Surfaces to Food
Work surfaces such as kitchen tabletops may contain bacteria as a result of contact with dirty equipment, raw food and people. If the surface is not cleaned thoroughly, the bacteria would contaminate any food that is in contact with the surface. For example:
Cartons that are stored on the floor would contaminate the surfaces if next placed on the tabletops.
People to Food
People can be a source of cross-contamination to food. This is because harmful bacteria live in and on our bodies, especially on and around our faces, hands and on our clothing. As they are usually present in small numbers, they do not make us sick. If these bacteria are transferred from our bodies or clothes to food and allow to multiply, the food can become unsafe.
For example:
Touching of raw meats and followed by slicing of cooked hams without washing hands between tasks.
Inadequate hand washing and poor personal hygiene of food handlers.
3. Why is cross-contamination in food a problem?
It may cause foodborne illness when the bacteria are transferred onto food that is ready-to-eat. For instance, a customer consumes a cooked chicken that comes into contact with raw meat; the customer will consume the bacteria found on the meats that could later make him or her feel ill.
source :http://www.ava.gov.sg/
