Soybean proteins are the most widely used source vegetable proteins in the meat industry because of several
interesting characteristics. As soybean is included in the group of ingredients potentially allergenic, if not
declared, it can be considered a hidden allergen, representing a potential risk to sensitised individuals. The
aim of this work was to optimise and apply DNA-based techniques for soybean detection in meat products,
as alternative to the currently used protein-based methods. The optimised polymerase chain reaction (PCR)
protocol targeting the soybean lectin gene enabled the detection of the addition of 0.1% and 0.5% of
hydrated textured protein, which corresponded to 0.01% and 0.06% (w ⁄ w) of soybean protein in
unprocessed and heat-processed pork meats, respectively. The established PCR technique, when applied to
commercial meat sausages (eighteen samples), confirmed the presence of soybean declared in nine samples
and indicated the presence of soybean in four samples with no labelled information about soybean.
Additionally, the event-specific PCR detection of Roundup Ready soybean was also performed, enabling
the detection of transgenic DNA in three samples.
