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

The oral mucosa is the first site of contact with food allergens, yet the influence of food matrices and oral processing on allergen release remains poorly understood. This study investigated the roles of bread matrix and mastication behaviors in the oral bio-accessibility of wheat allergens. Volunteers consumed breads with distinct structural profiles (baked, steamed, baguette; with/without shortening) under video monitoring. Results showed that the bread matrix did not alter the types of released proteins but significantly modulated their IgE-reactivity. The addition of shortening enhanced IgE-binding capacity, suggesting a lipid-mediated modulation of allergen release is likely through emulsion formation. Oral processing parameters correlated strongly with bolus properties and allergen immunoreactivity, highlighting that individual mastication behaviors personalize the exposure dose. 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.