Deamidation of Gluten Proteins as a Tool for Improving the Properties of Bread

The allergenicity of gluten proteins in foods made with wheat flour, including bread, is a serious public health concern. The deamidation of gluten proteins, a reaction that converts glutamine and asparagine residues to glutamic-acid and aspartic-acid residue, respectively, is an effective method for reducing allergenicity and improving physicochemical functions, including the solubility and surface properties of gluten proteins. The deamidation of gluten proteins following acid-, alkaline-, heat-, enzyme-, or cation-exchange-resin treatment yields increased solubility in aqueous solution and improved emulsifying, foaming, and gelation properties compared with untreated proteins. In addition, the deamidation of gliadin, a major allergenic protein in gluten, using carboxylated cation-exchange resin is reportedly effective at reducing its reactivity with the sera of patients that exhibit a positive radioallergosorbent test to wheat and oral allergenicity, including intestinal permeability, increased serum allergen, or allergen-specific immunoglobulin E (IgE) levels, FcɛRI expression on mast cell surfaces, and increased serum and intestinal histamine levels.