Ingredients

• 500g unbleached bread flour or all-purpose flour (used over several days)
• 500g filtered, chlorine-free water, room temperature (70–75°F / 21–24°C)

Optional (Recommended for Faster Fermentation)

• 100g whole wheat flour or rye flour (replace part of the white flour during the first few feedings)

Equipment

• 1 large glass jar (1-quart or larger)
• Digital kitchen scale
• Silicone spatula or wooden spoon
• Rubber band or marker
• Loose-fitting lid or clean kitchen towel
• Thermometer (optional)

Instructions

Day 1 – Create the Starter

1. In a clean glass jar, combine:
   • 100g flour
   • 100g room-temperature filtered water
2. Stir until a thick, smooth batter forms with no dry flour remaining.
3. Scrape down the sides of the jar.
4. Mark the level with a rubber band.
5. Cover loosely and leave at room temperature (70–78°F / 21–26°C) for 24 hours.

What to Expect:
The mixture may look unchanged today. This is completely normal as the natural fermentation process begins.

Day 2 – First Feeding

1. You may notice a few bubbles or a mild floury aroma.
2. Discard all but 100g of the starter.
3. Feed with:
   • 100g flour
   • 100g water
4. Mix thoroughly until smooth.
5. Cover loosely and let ferment for another 24 hours.

Day 3 – Fermentation Increases

By now, the starter should begin producing more bubbles and may have a slightly fruity or tangy aroma.

1. Discard all but 100g starter.
2. Add:
   • 100g flour
   • 100g water
3. Stir well.
4. Cover and let rest for another day.

Don’t worry if the starter rises and falls quickly—it is still developing.

Day 4 – Strengthening the Culture

The starter should now become noticeably more active.

Repeat the feeding:

• Keep 100g starter.
• Add 100g flour.
• Add 100g water.
• Mix until smooth.

The starter may double in size after feeding.

Day 5 – Check for Readiness

Your starter should now:

• Double in volume within 4–8 hours
• Be filled with bubbles
• Smell pleasantly tangy, fruity, or slightly yogurt-like
• Have a light and airy texture

Feed again:

• 100g starter
• 100g flour
• 100g water

If it isn’t consistently doubling, continue daily feedings.

Days 6–7 – Mature Starter

Continue feeding every 24 hours until your starter reliably doubles or triples after each feeding.

A mature starter should:

• Rise consistently after feeding
• Hold plenty of bubbles throughout
• Have a pleasant sour aroma
• Feel light and elastic when stirred
• Peak within 4–8 hours

Once it reaches this stage, it is ready for baking.

Daily Feeding Schedule

For frequent bakers:

• 50g mature starter
• 50g filtered water
• 50g bread flour

Mix well and allow it to rise until doubled before using.

Refrigerator Storage

If you bake once a week or less:

1. Feed the starter.
2. Leave it at room temperature for 1–2 hours.
3. Refrigerate in a loosely covered jar.

Feed it every 7 days.

Before baking:

• Remove from the refrigerator.
• Feed once or twice.
• Wait until it doubles before mixing your dough.

How to Know Your Starter Is Active

A healthy starter should:

• Double or triple in size
• Have many visible bubbles
• Smell pleasantly sour with fruity or yeasty notes
• Form a domed top before slowly falling
• Return to this pattern consistently after each feeding

Troubleshooting

Starter Isn’t Rising

• Move it to a warmer location (75–78°F / 24–26°C).
• Use filtered water if your tap water contains chlorine.
• Feed with some whole wheat or rye flour to encourage activity.
• Be patient—some starters take 7–10 days to mature.

Gray Liquid (Hooch)

A layer of liquid means the starter is hungry.

Pour it off or stir it back in if you prefer a more sour flavor, then feed the starter.

Unpleasant Smell

During the first few days, the starter may smell cheesy or slightly unpleasant as different microorganisms compete. This is a normal part of the process.

If you see pink, orange, green, or black mold, or fuzzy growth, discard the starter and start again with a clean jar.

Pro Tips

• Always weigh ingredients for accuracy.
• Use room-temperature filtered water.
• Keep the jar loosely covered to allow gases to escape.
• Clean the sides of the jar after each feeding.
• Feed at roughly the same time every day.
• A warm, draft-free environment encourages healthy fermentation.

Ways to Use Your Active Starter

Once mature, your starter can be used to make:

• Artisan sourdough bread
• Sandwich bread
• Focaccia
• Pizza dough
• Bagels
• English muffins
• Cinnamon rolls
• Soft pretzels
• Pancakes
• Waffles
• Crackers
• Brioche
• Dinner rolls
• Donuts
• Biscuits

Nutrition (Approximate per 50g active starter)

• Calories: 55
• Carbohydrates: 11g
• Protein: 2g
• Fat: 0.2g
• Fiber: 0.5g
• Sugar: 0g
• Sodium: 1mg

A Classic Active Sourdough Starter is the essential first step to exceptional homemade sourdough baking. With only flour, water, and a little patience, you’ll cultivate a thriving natural leaven that can be maintained indefinitely, providing incredible flavor, texture, and versatility for countless bread and baked goods recipes.