Effect of polysaccharide conjugation or transglutaminase treatment on the allergenicity and functional properties of soy protein

The soy protein-galactomannan conjugate prepared by the Maillard reaction removed the allergenicity of the 34 kDa protein which is frequently recognized by the IgE antibody in the sera of soybean-sensitive patients as a major allergen. Monitoring of polyclonal antibody titers by an indirect enzyme-linked immunosorbent assay and immunoblotting of rabbit sera, monoclonal antibody, and human allergic sera showed that soy protein-galactomannan conjugation was more effective in reducing the allergenicity of the soy protein than transglutaminase treatments and/or chymotrypsin. The soy protein-galactomannan conjugate was highly soluble at all pHs, while untreated soy protein was sparingly soluble at pH 4-6. Heat stability and emulsifying properties were greatly improved by conjugation with galactomannan.