Gluten-free flour fermented with autochthonous starters for sourdough production:Effect of the fermentation process

Refined rice flour and wholegrain quinoa and buckwheat flours were used to prepare gluten-free sourdoughs.Two autochthonous LAB strains were isolated,one from quinoa (Limosilactobacillus fermentum Q3) and the other from buckwheat (Lim.fermentum T5).Lactiplantibacillus plantarum ATCC8014 was used as a reference starter.Two fermentation processes were evaluated,a single-step process (30℃,24 h) named SD1,and a daily refreshment process (backslopping for 10 days) named SD2.Sourdoughs were freeze-dried prior to analyses.Pasting properties,pentosan and polyphenol contents,and antioxidant activity were analysed.Flour properties were significantly modified by fermentation.Polyphenol extractability increased during fermentation,which resulted in a higher antioxidant capacity,mainly through a reducing mechanism.Q3 and T5 strains produced the most remarkable modifications of flour properties.Differences were found between both fermentation processes,mainly as a result of the development of different microbiota.The single-step fermentation (SD1) showed to be a simple and appropriate method for improving flour properties.