Sourdough Starter #13

This is sourdough the old-fashioned way. No commercial yeast, no special ingredients. Just milk, unbleached flour, time, and the wild bacteria and yeast already floating around your kitchen.

Leave milk uncovered at room temperature for a full day. During that time, naturally occurring lactobacillus bacteria begin to colonize the milk and start producing lactic acid. You’ll notice it smelling slightly tangy. Then stir in the flour and let the mixture sit for another couple of days.

When it’s bubbling, smelling pleasantly sour (think yogurt-like tang, not rotten), and has roughly doubled in volume, your starter is alive and ready to use.

The scalding step for containers is critical and not just fussiness. Without commercial yeast to dominate, your starter depends on wild cultures winning the competition against unwanted bacteria. A dirty container tilts that competition the wrong way.

Kitchen Tips

• Use unbleached all-purpose flour. Bleached flour has fewer wild yeast spores and may not ferment properly
• Room temperature means 70-75°F (21-24°C). Too cold and nothing happens. Too hot and bad bacteria can take over
• If the starter smells truly foul (not sour, but rotten) or develops pink or orange streaks, throw it out and start over. That means the wrong organisms won
• Once active, feed your starter with equal parts flour and milk (or water) to keep it going

Variations

• Use whole wheat flour instead of all-purpose for a more robust, faster-fermenting starter
• Swap milk for water if you prefer a dairy-free starter (water starters are more common in modern sourdough baking)
• Add a teaspoon of honey to the initial mix to give the wild yeast a sugar boost at the start