What is sourdough bread?
Baking, one of the main processes of the food industry worldwide, has been carried out for millennia through the use of a consortium consisting mainly of yeasts of different genera (Candida, Saccharomyces, Kzachstania, etc), associated with various lactobacilli. This was, until the nineteenth century, the traditional way of making bread, which was replaced by the use of pressed yeast of the species Saccharomyces cerevisiae as the sole raising agent. In recent years, however, there has been a growing interest in the recovery of the use of sourdoughs with yeasts and natural lactobacilli, which results in a better structure and conservation of bread (production of lactic and acetic acid), increases its organoleptic properties (aroma and flavor) and favors the digestibility of the masses.
What is a Sourdough?
A sourdough is a microbial consortium of bacteria and yeast growing in a mix of water and flour. It has 100 hundred times more bacteria than yeast cells.
During baking, maillard reactions between amino acids and reducing sugars take place. This gives bread –and other browned food- its distinctive roasted flavor.
To ferment the dough, sourdough is mixed with more flour, water and salt. Yeast consumes glucose and produces carbon dioxide (helps bread rise) and ethanol (will boil off during baking).
Bacteria consume glucose and maltose and produce lactic acid and aromatic compounds.