Food Allergy Association of Wisconsin Inc.

Cross contamination

Cross contamination refers to a food being inadvertently contaminated with food proteins other than those listed on the food label during the course of its being prepared, stored or served. These traces of allergenic proteins can cause reactions in individuals having food allergies to those proteins.

Cross contamination can occur at home, when you prepare or serve food on contaminated surfaces. An example of this is using a the same knife to spread jam on a sandwich that had been previously used to spread peanut butter. Another example is when you prepare food with utensils, mixing bowls or pans that may have been shared with other food that contains an allergen. Cross contamination in the home can also occur through the use of household, body, bath and pet food products that contain allergenic food ingredients.

The manufacturing process can also result in cross contamination of food products. Production lines are often shared with food products that contain many various ingredients. In using shared equipment, there is a chance that traces of food allergens may be left on the production lines resulting in cross contamination of other products.

It is common, for instance, for manufacturers to make products without nuts on the ingredient label using the same equipment that is also used for making other foods that do contain nuts. It is also common for products without milk ingredients to be made on equipment shared with products that do contain dairy ingredients. Cross contamination of products from other allergenic proteins can occur in a similar manner.

Common examples of products that may have cross contamination issues from shared equipment include many baked goods, cereals, processed foods and candy. It is very important to remember that some food manufacturers will label their products to indicate the possibility of cross contamination, but many manufacturers do not.

The improved food allergen labeling laws scheduled to go into effect in 2006 will not require manufacturers to list common allergenic ingredients resulting from shared equipment and cross contamination issues. It will still remain the responsibility of consumers to read labels carefully and call manufacturers to be sure that each food is safe for their unique allergy issues