From wheat sourdough to gluten-free sourdough: a non-conventional process for producing gluten-free bread

摘要

Gluten-free (GF) sourdough was prepared from wheat sourdough and analysed both in fresh (GFS) and dried forms (DGFS). The gluten content in each GF sourdough sample was ＜20 mg kg~(-1). The dough leavening capacity and the properties of the bread samples were investigated and compared to those of bread prepared using bakery yeast (Saccharomyces cerevisiae). Two commercial rice-based mixtures (different for the presence/absence of buckwheat flour) were used to prepare bread samples. In GFS, lactic acid bacteria (LAB) and yeasts were found in amounts corresponding to 10~8 and 10~7 CFU g~(-1), respectively, whereas both LAB and yeasts were detected in lower amounts (about 10~6 CFU g~(-1)) in DGFS. When used in bread-making, both GFS types produced significant dough acidification and exhibited good dough development during proofing, resulting in loaves with specific volume values between 3.00 and 4.12 mL g~(-1), values similar to those obtained for reference bread (3.05÷4.15 mL g~(-1)). The use of GFS was effective in lowering the bread staling rate during storage for up to 7 days.