[The influence of thermal load on the immunochemical detection of dried blood plasma supplements in meat mixtures].

Addition of blood plasma to meat products is not permitted in the FRG unless these products are heat processed using an internal temperature of 80 degrees C (German regulation of meat and meat products: "Verordnung für Fleisch und Fleischerzeugnisse"). Such heat process may have an unfavourable effect on the detectability of blood plasma. Since blood plasma or dried plasma may originate from different animal species (porcine or bovine) two different anti dried blood plasma-sera (porcine and bovine) are required for immunochemical analysis. The varying quality of these sera has to be considered when interpreting the results. Seven M urea extract turned out to be suitable for detection of dried plasma additives and proved to be highly effective particularly when examining heated samples. Both the gel-diffusion and the electro immuno assay proved useful for the detection of dried blood plasma, provided the examined extracts had been adequately diluted. Immunochemical reactivity was hampered by the heat process which was given to the sample. Accordingly, the concentration of the plasma in a particular sample cannot be determined unless the time/temperature data of the process applied to the sample were given and model samples were tested for comparison.