Abstract
The application of a novel cereal ‘Tritordeum’ in sourdough fermentations for making bread was demonstrated. The sourdough was propagated with traditional backslopping procedure throughout 10 days. Culture-dependent and culture-independent approaches were used to explore the microbial ecology during sourdough preparation and propagation. Higher microbial diversity was found whitin the first days of propagation, while as sourdough reached maturity (day 5), the diversity started decreasing. The microbiota evolution of Tritordeum sourdough, shifted from dominance of Weisella to Lactiplantibacillus genera after 5 days of propagations. Lactic acid bacteria had a constant increase throughout the propagations starting with cell density ca. 3.9 up to ca. 8.0 log CFU g-1. Among the lactic acid bacteria isolates, Weisella confusa/cibaria and Weissela paramesenteroides had the highest prevalence until day 5, while during further propagations Lactiplantibacillus plantarum. Yeasts were in very low cell density (ca. 2 log CFU g-1) until the fourth backslopping and gradually increased until day 10 (ca. 5 log CFU g-1), with Saccharomyces cerevisiae beeing the most isolated and dominant species. Biochemical properties of Tritordeum sourdough such as, lactic and acetic acid concentrations increased throughout propagations, and reflected proportionally the decrease of fermentation quotient (range 3.5 to 4.0). Utilization of glucose, fructose and sucrose followed the progressive increase in manitol concentrations, while nutritional potential (total phenol content, antioxidant activity, dietary fiber content and total free amino acids), elevated during the subsequent sourdough propagations. Antinutritional factors (phytic acid and raffinose) were reduced to minimal concentrations. Finally, texture analysis of Tritordeum sourdough bread demostrated better cohesiveness, resilience and firmness compared to baker’s yeast breads, confirming its potential for improving functionality and use in sourdough biotechnology.