The present invention relates to the use of an enzymatic method for treating flour, semolina and protein extracts derived from cereals known to stimulate a pathological immune response in patients affected by Celiac Disease (CD). Said treatment drastically reduces or completely eliminates the toxicity of gluten or similar products derived from other cereals. The method uses the catalytic activity of microbial transglutaminase and, in particular, its ability to bind proteins in cereal flour or semolina to an alkylated (C1-C4) derivative of lysine. After the treatment said proteins extracted from flour show a substantially lowered immuno-stimulatory activity in celiac patients T lymphocytes.
