Food allergy is increasing in prevalence, posing aheavier social and financial burden. At present, there is still no widely accepted treatment for it. Methods to reduce or eliminate the allergenicity of trigger foods are urgently needed. Technological processing contributes to producing some hypoallergenic foods. Among the processing methods, the Maillard reaction (MR) is popular because neither special chemical materials nor sophisticated equipment is needed. MR may affect the allergenicity of proteins by disrupting the conformational epitope, disclosing the hidden epitope, masking the linear epitope, and/or forming a new epitope. Changes in the allergenicity of foods after processing are affected by various factors, such as the characteristics of the allergen, the processing parameters, and the processing matrix, and they are therefore variable and difficult to predict. This paper reviews the effects of MR on the allergenicity of each allergen group from common allergenic foods.

Ovalbumin (OVA), one of the major allergens in hen egg white, and has widespread use in experimental models of allergy. The aim of this research was to assess the effect of glycation and heat treatment on the potential allergenicity of OVA prepared from hen egg white. Secondary and tertiary structures of OVA were also characterised to show the relationship between potential allergenicity and the conformation of OVA after heating and glycation. Glycation significantly reduced the potential allergenicity of OVA tested with egg allergy patients’ sera, which was caused by conformation changes. An increased IgG reactivity was measured using rabbit anti-OVA and was supposed to be caused by protein unfolding which exposed hidden epitopes. Heating reduced the potential allergenicity of OVA at the expense of increased IgG reactivity. It is suggested that conformational changes of OVA induced by glycation and controlled heating significantly reduced its potential allergenicity.