Allergenic Reactivity of Various Soybean Products as Determined by RAST Inhibition

Allergenic reactivity of soybean products (sprouts‐Sp, tempeh‐T, tofu‐To, miso‐M, mold hydrolyzed soy sauce‐MHS, acid‐hydrolyzed soy sauce‐AHS and hydrolyzed vegetable protein‐HVP) was determined using RAST inhibition. All products inhibited binding of serum IgE from a pool of soy‐allergic adults to raw soybean extract bound to microcrystalline cellulose, showing competitive inhibition with increasing protein. M.T. To and MHS showed competitive inhibition only at much higher protein concentrations, suggesting fermentation may alter or desyroy allergenic epitopes. Selectle destruction of ep‐itopes was seen for MHS. To. and nossiblv M and T where inhibition curve slopes were not identical to intact material. Probably protein(s) with antigens common to raw soybean survived during processing of HVP and germination of sprouts. Based on RAST inhibition, these products are potentially hazardous to soybean‐allergic individuals.