Influence of dextran synthesized in situ on the rheological, technological and nutritional properties of whole grain pearl millet bread.

Highlights • Bioprocessing increased free phenolic content and antioxidant activity of millet. • Bioprocessing led to a large quantity of dextran production in millet. • Dextran presence markedly enhanced dough rheology and bread quality parameters. • Amylopectin recrystallization was significantly hindered by the dextran produced. • Bioprocessing reduced the digestible starch and improved the digestible protein. Abstract The effect of dextran produced in situ by Weissella confusa on the structure and nutrition quality of whole grain pearl millet bread containing 50% of wheat flour was investigated. NMR spectroscopy analysis indicated that the dextran formed by the strain consisted of a α-(1 → 6)-linked linear backbone and 3% α-(1 → 3) branches, and had a molar mass of 3.3 × 106 g/mol. In situ production resulted in 3.5% dextran (DW) which significantly enhanced the dough extensional properties, increased the bread specific volume (∼13%) and decreased crumb firmness (∼43%), moisture loss (∼15%) and staling rate (∼10%), compared to the control millet bread. DSC analysis showed that amylopectin recrystallization was significantly reduced in the bread containing dextran. In situ dextran production altered the nutritional value of millet, leading to increased free phenolic content (∼30%) and antioxidant activity. It also markedly lowered the bread predicted glycemic index and improved in vitro protein digestibility. [ABSTRACT FROM AUTHOR]