Sourdough is being researched for its effectiveness in helping people with celiac disease and gluten sensitivities. Charlene Van Buiten, PhD, an assistant professor of food science and human nutrition at Colorado State University, shared how sourdough can alleviate problems with gut health in an article she wrote for Baking Europe.
The live, active cultures contained in fermented foods like kimchi, pickles, kombucha and yogurt have been scientifically proven to increase the diversity of microorganisms in the digestive tract. A recent study from researchers at Stanford found a diet rich in fermented foods decreases markers of inflammation.
The same health benefits cannot be attributed to sourdough, though, because the live microorganisms are killed during baking.
“As a result, the health benefits associated with sourdough bread are derived not from probiotics, but from the actions of the starter culture over the course of fermentation,” Van Buiten writes. The microorganisms present in starter cultures “have been shown to improve mineral bioavailability in sourdough bread in comparison to conventional yeast-fermented bread through the production of organic acids and enzyme phytase, which promote the degradation of anti-nutritional phytates found naturally in flour. “
Sourdough bread has other positive effects, too. The increased acidity of sourdough forms resistant starch, so starch is not converted to sugar by the gastrointestinal tract but instead “acts more like fiber.” Sourdough fermentation also increases the amount of free amino acids in bread, improving the protein digestibility. Sourdough bread made from starter cultures are also lower on the glycemic index.
Van Buiten points out case studies “have suggested that traditional sourdough fermentation can improve gastrointestinal tolerance to bread in comparison to conventional yeast fermentation,” but only for individuals with non-celiac gluten sensitivity. Few studies have explored how sourdough would impact someone with celiac. A study would need to explore gluten degradation within sourdough fermentation, a key sensitivity for individuals with celiac.
“Though no evidence currently exists where traditional artisanal sourdough fermentation provides protection against the harmful gluten peptides associated with celiac disease pathogenesis, scientists are exploring novel strategies to employ the known gluten-degrading capabilities of sourdough-derived microorganisms in the production of baked goods,” Van Buiten adds.
Read more (Baking Europe)