Mechanisms behind matrix–protein interactions influencing receptor-based and chromatographic detection of food allergens: A case study with a fruit based snack

Food allergies represent an important food safety problem. The only effective treatment for food allergies is the complete avoidance of the offending foods or foods containing undeclared traces of allergens. In order to verify whether foods are contaminated with allergens reliable detection methods are needed. Currently enzyme-linked immunosorbent assays (ELISA) especially commercial ones are routinely used by the food industry and enforcement agencies. However, the reliability of such receptor based methods can be affected by the matrix in several ways. In this study we showed that the proteins/allergens can strongly bind to the matrix making them inefficient for the extraction as proven by a high-performance liquid chromatography method. On the other hand, especially in the case of ELISA methods, the matrix can non-specifically bind to the antibodies leading to false positive results. In conclusion, outmost care should be taken when interpreting the results of the methods used for analysis of traces of food allergens especially when important decisions about the acceptance or removal of the products from the market should be taken.