The invention describes the patterns of deamidation in gluten, and it is found that this is highly dependent on the spacing between the glutamine and proline residues. This knowledge can be used to predict novel T cell stimulatory gluten peptides. Several newly defined peptides and epitopes are provided. Also, the finding can explain the formation of neo-epitopes in autoimmune diseases such as RA (rheumatoid arthritis), MS (multiple sclerosis), SLE (systemic lupus erythomatosus), SS (Sjogren syndrome) and DB (diabetes). Several neo-epitopes and the peptides that are substrate for deamidation are provided. Further, the inventions provides for methods for detecting these peptides and epitopes and methods for making food more suitable for celiac disease patients.