An anti-gliadin monoclonal antibody (IFRN 0033) raised to total gliadin protein from wheat has been assessed for its ability to recognise, at the ultrastructural level, gluten proteins in grain and bread. An indirect, two-step, immunolabelling procedure using colloidal gold as a readily identifiable marker for electron microscopy was successfully used to locate gluten proteins in wheat and bread. Storage protein bodies in developing grain, and protein matrix in mature grain, immunolabelled, and there was no cross-reactivity with aleurone proteins or non-storage proteins associated with the endosperm starch. Epitopes recognised by IFRN 0033 were not destroyed by the baking process. IFRN 0033 bound strongly to the cut surface of breadcrumb immunolabelled before embedding, but, apart from isolated fibrils, did not recognise the gluten-gas cell interface.