Researchers in Europe conducted a novel study which utilized a highly specialized sourdough lactobacilli containing peptidases that have the ability to hydrolyze Pro-rich peptides, including the 33-mer peptide, which is the main culprit in the immune response associated with celiac disease. The sourdough bread in the study was made from a dough mixture that contained 30% wheat flour and other nontoxic flours including oat, millet, and buckwheat, which was then started with the specialized lactobacilli. After 24 hours of fermentation all 33-mer peptides and low-molecular-mass, alcohol-soluble polypeptides were almost totally hydrolyzed.
For the next step in the study the researchers extracted proteins fro the sourdough and used them to produce a "peptic-tryptic digest" for in vitro agglutination tests on human K 562 subclone cell. The agglutinating activity of the sourdough proteins was found to be 250 times higher that that of normal bakers-yeast or lactobacilli started breads.
A double blind test was then conducted in which 17 celiac disease patients were given 2 grams of gluten-containing bread started with bakers yeast or lactobacilli. Thirteen of them showed distinct, negative changes in their intestinal permeability after eating the bread, and 4 of them did not show any negative effects. The specially prepared sourdough bread was then given to all 17 patients and none of them had intestinal permeability reactions that differed from their normal baseline values.
The researchers conclude: "These results showed that a bread biotechnology that uses selected lactobacilli, nontoxic flours, and a long fermentation time is a novel tool for decreasing the level of gluten intolerance in humans."