Immunohistochemical detection of soya protein - optimisation and verification of the method

A functional immunohistochemical method for soya proteins detection was developed. The procedure is based on the avidin-biotin complex (ABC) method that attains sufficient sensitivity. The method was verified by the analysis of the model samples of different forms of soya additives containing various concentrations of soya isolate. The detection limit of soya present in the model samples was 0.5%. Different possibilities of the background staining were tested. The best results were obtained with the background staining according to Calleja. The results were confirmed by the accredited indirect ELISA method. The method allows the identification of various forms of soya proteins such as isolates, texturates, concentrates, and flour.