Determination of peanut traces in food by a commercially-available ELISA test

Peanuts are one of the most important food allergens. The unintended ingest ion of peanut has caused severe allergic reactions and even deaths in sensi tive individuals. Specific methods with sensitivities in the low ppm range are necessary? to check whether a food contains relevant amounts of peanut protein. Based on a commercially-available ELISA test, a test protocol was established for the detection and semi-quantitative determination of peanut traces in a wide range of products, including chocolate and chocolate conf ectionery, ice cream and bakery goods. The rest was rendered semi-quantitat ive by including a standard curve prepared from different peanut materials and by adapting the extraction procedure. Using the extraction buffer suppl ied with the kit, only 2-3% of peanut protein added to dark chocolate could be recover-ed By using a fish gelatine containing extraction buffer; recov eries of 60-90% and a detection limit of 2 mg peanut protein kg(-1) product were achieved for this matrix. Comparable results were established for oth er products with similar values for extraction with or without fish gelatin e. No false positive results were observed. With this a sensitive method is available for the determination of peanut traces in a wide range of raw ma terials and finished products. The detection limit of 2 mg peanut protein k g(-1) product is satisfactory if compared to the lowest tolerable dose of p eanut protein as determined in recent challenge studies.