Health News: Standard Test May Miss Food Ingredients That Cause Milk Allergy

The standard test used to detect milk-protein residues in processed foods may not work as well as previously believed, sometimes missing ingredients that can cause allergic reactions, a scientist reported at the recent National Meeting & Exposition of the American Chemical Society.

Joeseph L. Baumert, who headed the study, explained that thermal and nonthermal processing of foods can change the proteins responsible for milk allergy in ways that make the proteins harder to detect using the standard enzyme-linked immunosorbent assay (ELISA) test. Processing may still leave the milk proteins capable of causing itchy skin, runny eyes, wheezing, and other sometimes more-serious symptoms of milk allergy, despite the inability to detect the milk residue.

According to Baumert, heating and other processing of foods can make milk proteins aggregate together so it is difficult to get the milk proteins into solution, which enables them to be detected by the antibodies in ELISAs. The clumping, however, does not necessarily destroy the protein’s ability to trigger an allergic reaction in sensitive people.

Baumert’s team studied and documented how ELISAs perform on several measures of accuracy when milk proteins undergo changes in foods that are boiled, baked, fried, or heated in other ways. “The results of these studies could be utilized by commercial ELISA kit manufacturers to improve tests for dectection of milk residue in processed food products,” said Baumert.