Oral bio-accessibility of wheat allergens: the roles of food matrices and oral processing behaviors

Abstract

The oral mucosa is the first site of contact with food allergens, yet how food matrices and oral processing behaviors influence the release and immunoreactivity of allergens during mastication remains poorly understood. This study investigated the roles of bread matrix and oral processing in the oral bio-accessibility and IgE-reactivity of wheat allergens. Different breads (baked, steamed, baguette) with and without shortening were characterized and consumed by volunteers under video monitoring. Bread matrix did not alter the types of released proteins but significantly modulated their IgE-reactivity. The addition of shortening notably enhanced the IgE-binding capacity in certain baked breads, indicating a lipid-mediated modulation of allergen release, potentially through emulsion formation. Oral processing parameters correlated strongly with both bolus properties and the immunoreactivity of released proteins, highlighting that individual mastication behavior personalizes the exposure dose of immunoreactive allergens. High-molecular-weight (MW) and low-MW glutenin, serpin, GAPDH, and α-amylase inhibitors were identified as the primary bio-accessible wheat allergens released in the oral phase. This study provides a new perspective on the initial exposure pathway of wheat allergens from the novel lens of allergen-matrix interactions.