Allergies to lupin foods assessed
The lupin is an increasingly economically important crop. Worldwide, over 2 million tonnes were produced in 1999, a huge increase over the previous two decades. The lupin crop is particularly suitable for growth in Europe and different varieties can be grown in all European regions. The seeds have a high protein, high fibre content together with a very low glycaemic index (GI), ideal for diabetic patients. As part of the HEALTHY-PROFOOD project funded by the EC, project partners developed food and drink products with a lupin base targeting the health food market. As part of the project's multi-disciplinary approach to the commercial production of lupin-based foods, it was possible to conduct a highly comprehensive study. This included all aspects of food technology and nutrient pathology. In particular, researchers at Biocentrum investigated the levels of potential allergenicity of raw lupin and its products. The allergic, or IgE response induced by raw and processed lupin protein was measured in an animal model. This response is a prelude to the production of antibodies before an allergenic cascade. The lupin protein γ-conglutin was found to induce an allergic response when crude lupin extract was used as opposed to processed protein. The results regarding γ-conglutin tie in with allergic tests for the same protein on human sera. The good news therefore is that it is possible to produce lupin protein extract that is not allergenic and a consequent risk to consumers. The capability of peanut and lupin proteins to produce an allergic response was compared. Different proteins from the two sources that had no sequence homology were tested and the phenomenon of cross reactivity was observed. This is when allergic symptoms may be induced by an allergen without prior exposure. Results from this research show that lupin-based products can be a healthy protein rich source in the diet that can replace other sources such as milk and egg. The findings regarding allergenicity of lupin proteins form a research base whereby consumer safety interests can continue to be protected at the highest level.
