Food Allergen Test May Not Accurately Detect Milk Proteins

The test usually used to detect milk proteins in processed food may not work accurately with all foods, sometimes missing proteins that could cause a reaction in people with milk allergies, which are among the most common of all food allergies.

Joseph Baumert, the researcher who headed the study, explained to Laboratory Equipment.com that processing of foods (both thermally and using non-thermal methods), can change the proteins that are responsible for milk allergies into a form that is more difficult to detect using the standard test, which is known as ELISA (or the enzyme-linked immunosorbent assay). The same processing may not render the milk proteins unable to activate the immune system, causing wheezing, itchy skin, runny eyes, and other symptoms.

Food processors use ELISA tests to ensure that their processed foods are free of milk proteins that could trigger a milk allergy. Baumert explained "The results of these studies could be utilized by commercial ELISA kit manufacturers to aid in improving ELISAs for detection of milk residue in processed food products... regardless of the type of processing that is used."

Baumert, who is with the University of Nebraska, explained that heating (such as through boiling, baking, or frying) and other food processing techniques can cause the milk proteins to clump together or alter their molecular structure, making them more difficult for the test to detect. However, the milk proteins are likely to maintain their ability to trigger a food allergy.