Soy is one of the so-called big eight allergens that are also regulated in the EU. This is why it has to be labeled as an ingredient on food in almost all countries around the world.
The soybean (glycine maxima) from the family of legumes consists of more than 35% proteins and therefore serves as an important plant-based source of protein for human consumption. Soy products such as soy sauce, soy milk, tofu, miso or tempeh are growing in popularity. Furthermore, soy is often used for oil production and to manufacture the emulsifier soy lecithin. Nowadays, more and more soy products are sold on the market. Parallel to this, there are more soy allergies developing around the world. The increased use of soy in food production can lead to accidental cross contaminations of food.
Even small concentrations of approx. 5 mg of soy protein can trigger food allergies. Therefore, the allergen is subject to labeling in many countries. Gly m1 to Gly m6 are considered the allergenic proteins of the soybean. The main storage proteins are ß-conglycinin (Gly m5) and the heat-stable glycinin (Gly m6). ß-conglycinin represents the main allergen in childhood. Glycinin and ß-conglycinin can trigger anaphylactic reactions in allergic patients. If one of the aforementioned proteins is detected, e.g. by means of an ELISA test, allergy sufferers must avoid this food.
Detection of soy in processed foods
Specially processed or highly heated food can contain soy proteins that are not recognized using common analytical methods (excluding RIDASCREEN®FAST Soya, Art. No. R7102). The main reason for this is the lack of adequate antibodies and an effective extraction.
In addition to the ELISA test, R-Biopharm developed a lateral flow test that can be used to detect native or highly heated soy on surfaces. RIDA®QUICK Soya (Art. No. R7103) is a qualitative, immunochromatographic swab test used for hygiene monitoring in production lines and in the laboratory. At the moment, the RIDA®QUICK Soya test is the most sensitive lateral flow test used to detect soy on surfaces (0.5 μg soy protein/100 cm²) and is better than other analytical methods because it can detect processed protein. The antibodies used in the test detect, in particular, heated glycinin (Gly m6), one of the main allergens in soy and ß-conglycinin (Gly m5) another important allergen. An extraction at 100 °C results in the denaturation of all soy proteins and thus, enables efficient detection due to the antibodies.
RIDA®QUICK Soya can be used as a swab test for the soya determination on surfaces in the hygiene control and for the qualitative detection of soya in raw material and processed food.
RIDASCREEN®FAST Soya is a sandwich enzyme immunoassay for the quantitative analysis of native and processed soya proteins in food.
SureFood® ALLERGEN Soya
SureFood® ALLERGEN Soya is a PCR kit for the qualitative detection of DNA from soya.