Comparison of analytical techniques for qualitative detectionof soybean derivatives in meat products

Abstract

In Argentina, SENASA is the organization responsible for the inspection of establishments that manufacture meat products, and these products, in turn, are regulated by the Argentine Food Code. This regulation allows the addition of soybean derivatives in sausages as binders and/or extenders, but, the use in cured meats is prohibited. The aim in this framework was to compare the techniques of microscopy, enzyme immunoassay and real-time polymerase chain reaction (ELISA and Real-Time PCR, respectively) for the detection of soybean in meat products. For this purpose, 4 matrices of sausages and cured meats fortified with 1% soybean derivatives and 20 commercial samples were analyzed. In all fortified samples, the presence of soybean was detected by the three methodologies, and all commercial samples were in compliance with the legislation. Although the three techniques are suitable for the proposed objective, it can be concluded that microscopy has the advantage of being low cost, however, the number of samples that can be observed simultaneously is limited and depends on the expertise of the analyst. One disadvantage of the ELISA technique is the cost of commercial kits, also, that a certain amount of samples must be gathered to optimize its use. Finally, the method based on DNA detection allows to analyze a large number of samples simultaneously in a short time with high sensitivity and specificity; considering this, as well as the stability of the DNA molecule against heat treatments used in food processing, the PCR technique is presented as a reliable alternative tool. In addition, a more specific development of the Qualitative PCR method will allow, in the future, to quantify the content of soybean in different food matrices.