Metabolic profiling of sourdough fermented wheat and rye bread

• Published in: Scientific reports Vol. 8; no. 1; pp. 5684 - 11
• Main Authors: Koistinen, Ville M., Mattila, Outi, Katina, Kati, Poutanen, Kaisa, Aura, Anna-Marja, Hanhineva, Kati
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 09-04-2018; Nature Publishing Group
• Subjects: 631/45/320; 631/61; Amino acids; Bacteria; Baking; Bases (nucleic acids); Bioactive compounds; Fermentation; Grain; Health promotion; Humanities and Social Sciences; Insulin; Lactic acid; Lactic acid bacteria; Metabolism; Metabolites; multidisciplinary; Peptides; Phenolic acids; Phenols; Science; Science (multidisciplinary); Sourdough; Wheat; Yeasts
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-018-24149-w

Sourdough fermentation by lactic acid bacteria is commonly used in bread baking, affecting several attributes of the final product. We analyzed whole-grain wheat and rye breads and doughs prepared with baker’s yeast or a sourdough starter including
Candida milleri
,
Lactobacillus brevis
and
Lactobacillus plantarum
using non-targeted metabolic profiling utilizing LC–QTOF–MS. The aim was to determine the fermentation-induced changes in metabolites potentially contributing to the health-promoting properties of whole-grain wheat and rye. Overall, we identified 118 compounds with significantly increased levels in sourdough, including branched-chain amino acids (BCAAs) and their metabolites, small peptides with high proportion of BCAAs, microbial metabolites of phenolic acids and several other potentially bioactive compounds. We also identified 69 compounds with significantly decreased levels, including phenolic acid precursors, nucleosides, and nucleobases. Intensive sourdough fermentation had a higher impact on the metabolite profile of whole-grain rye compared to milder whole-grain wheat sourdough fermentation. We hypothesize that the increased amount of BCAAs and potentially bioactive small peptides may contribute to the insulin response of rye bread, and in more general, the overall protective effect against T2DM and CVD.