Detection of Peanuts in Commercially Processed Foods by an Enzyme-Linked Fluorescent Immunoassay

Enzyme-linked fluorescent immunoassay에 의한 가공식품 중 땅콩의 검출

  • Published : 2009.02.28


In this study we analysed for peanuts in processed foods using an enzyme-linked fluorescent immunoassay (ELFA), and compared the results with labeled ingredients. Crude peanut protein (CPP) was immunized into rabbits to produce specific antibodies(Ab). A sandwich ELFA was established using anti-CPP Ab and Ab-horseradish peroxidase (HRP) conjugate. The cross-reactivities of the Ab toward CPP, peanuts, almonds, soybeans, and walnuts were 100, 9.8, $1.1{\times}10^{-2},\;4.4{\times}10^{-3}$, and 0%, respectively. The samples included 19 items consisting of biscuits, snacks, chocolates, and so on. The results from the sandwich ELFA showed that peanuts were contained in 7 of the processed food items, among which, 5 items were labeled as having peanuts present but 2 items were not. One of the 2 items that was peanut-detected but unlabeled was a biscuit labeled to contain almonds and assayed to contain $2.1{\times}10^{-3}%$ peanuts, which might have been due to the weak cross-reactivity of the Ab toward almonds. The other item was a snack labeled to contain soybeans and assayed to contain 0.098% peanuts, which might have been due to peanut cross-contamination during processing, since the crossreactivity of the Ab toward soybeans was very weak. These results suggest that ELFA is a good tool to detect peanuts in processed foods, and allergens in certain processed foods should be labeled correctly.


peanuts;detection;specific antibody;enzyme-linked fluorescent immunoassay (ELFA)


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