surdeigen

Surdeigen, or the sourdough starter, is a living leavening culture used in bread baking. It consists of flour and water that have been allowed to ferment, hosting a community of wild yeasts and lactic acid bacteria. As these microorganisms feed on the flour’s sugars, the mixture becomes bubbly and acidic, capable of leavening dough and contributing complex flavors.

Maintaining surdeigen requires regular feeding with fresh flour and water to sustain the microbial population. Starters can vary in hydration: a liquid starter is typically near 100% hydration, while a stiff starter is drier. Common practice is to discard part of the starter and replenish with fresh flour and water in equal weights, for example 100 g starter, 100 g flour, and 100 g water.

Before baking, the starter is refreshed and allowed to become active, doubling in size and showing bubbles. A portion of the starter is kept for ongoing maintenance, while the remainder is used to inoculate dough. The starter’s activity and flavor depend on temperature, feeding frequency, flour type, and hydration.

Uses and flavor: Surdeigen provides leavening without commercial yeast and imparts a characteristic tang and depth of aroma. It is well suited to breads based on rye or whole grains, but is used across many bread styles.

Storage and safety: When kept at room temperature, regular feedings are usually required; refrigerated storage allows longer intervals between feedings. For long-term storage, it can be dried or frozen. Signs of spoilage include off smells, pink or orange coloring, or visible mold; such starters should be discarded.