Rye sourdough

Rye sourdough is a type of bread made using a starter culture of wild yeasts and lactic acid bacteria, traditionally fermented with rye flour and water. This slow fermentation process gives sourdough its characteristic tangy flavour and chewy texture. The starter culture is maintained and fed regularly, and a portion is used to leaven subsequent batches of bread.

Rye sourdough is primarily used as a bread product, valued for its distinct flavour profile and texture. It is also sometimes used as a base for croutons or breadcrumbs. The fermentation process can also contribute to the bread's keeping qualities.

Rye sourdough is not an additive and does not have an E-number. The fermentation process may increase the bioavailability of certain nutrients in rye flour. Some research suggests that sourdough fermentation can lower the glycaemic response compared to conventional bread, though evidence is mixed. The Food Standards Agency (FSA) and Food Standards Scotland (FSS) do not set specific limits for sourdough consumption.