Influence of starch addition and dough microstructure on fermentation aroma production by yeasts and lactobacilli

The work hypothesis of this paper was that during fermentation processes the chemico-physical interactions of the microbial metabolites with food matrix affects not only their retention, but the metabolic activity of the microorganisms. The influence of starch addition to liquid fermentation systems simulating sourdough and inoculated with pure and mixed population of Saccharomyces cerevisiae, Candida milleri and Lactobacillus sanfranciscensis significantly enhanced the production of selected metabolites. Moreover the starch addition interfered with the response of S. cerevisiae, C. milleri and L. sanfranciscencis when exposed to conditioned media of L. sanfranciscensis resulting in an increasing production of alcohols, isovaleric acid and of a key odorant like γ-decalactone. Under real conditions, the microstructure of the dough matrix significantly affected the metabolites production and cell activity.