Sourdough¶

While exploring healthier eating habits, I came across sourdough and sourdough bread, and decided I want to give it a try.

Key Terms and Concepts¶

Sourdough Starter: A live culture of wild yeast and bacteria made from flour and water. It's the natural leavening agent that makes sourdough bread rise.
Levain (or Leaven): A specific portion of sourdough starter that is fed in preparation for being mixed into a bread dough. For many home bakers, "starter" and "levain" are used interchangeably.
Discard: The portion of the starter you remove before a feeding. This helps manage the starter's size and keeps the yeast culture healthy. Discard can be used in many other recipes like pancakes or crackers.
Active Starter: A starter that has been recently fed and is at its peak of activity—bubbly, expanded (often doubled) in volume, and ready for baking.
Float Test: A simple way to check if your starter is ready. A small spoonful of active starter should float in a glass of water.
Hydration: Refers to the amount of water relative to the amount of flour in a dough, expressed as a percentage. Higher hydration doughs are wetter and can be more challenging to handle, but often result in a more open crumb.
Autolyse: The initial rest period after mixing just the flour and water in a recipe. It helps the flour absorb the water fully and begins gluten development without kneading.
Bulk Fermentation: The dough's first and longest rising period, where it develops most of its flavor and strength.
Stretch and Fold: A gentle technique of stretching and folding the dough during bulk fermentation to build gluten strength without traditional kneading.
Proofing (or Final Proof/Second Rise): The final rise of the shaped dough before it's baked.
Scoring: Making a slash on the surface of the dough with a sharp blade right before baking. It allows the bread to expand predictably in the oven.
Oven Spring: The rapid initial rise of the dough when it's first placed in the hot oven.
Crumb: The texture and pattern of holes inside the finished loaf of bread.

Choosing the Best Flour for Each Phase¶

The type of flour you use is one of the most significant factors in sourdough baking, affecting everything from the starter's activity to the bread's flavor, texture, and nutritional value.

Flour Types¶

Bread Flour: A high-protein white flour. Its strength creates a chewy texture and helps loaves hold their shape, resulting in a taller rise.
All-Purpose Flour: A medium-protein white flour. A versatile option that creates a slightly softer loaf compared to one made with bread flour.
Whole Wheat Flour: A whole-grain flour that includes the bran, germ, and endosperm. It offers more nutrients and a nuttier, earthier flavor but can result in a denser loaf.
Rye Flour: A whole-grain flour that is high in nutrients and enzymes that boost fermentation. It imparts a distinct, tangy flavor but has low gluten potential, leading to denser, stickier doughs.
Heritage/Ancient Grains (e.g., Spelt, Einkorn): These are less-common grains that have not been modernized. They offer unique flavors and nutritional profiles but can have variable gluten strengths.

Sourdough Phases¶

1. Creating the Sourdough Starter¶

To create a vibrant and resilient starter, we need to provide the best possible environment for wild yeast and beneficial bacteria to thrive. The microbes we want to cultivate are most abundant on the outer hull (the bran) of the grain.

The best option is a blend of whole-grain and white flour. Whole-grain flours like Rye or Whole Wheat introduce a high concentration of yeast and nutrients, essentially seeding the starter. White flours like Bread Flour provide easily accessible food (simple starches and sugars) for that new colony to consume and grow. A 50/50 blend of whole wheat and bread flour is a reliable choice to build a strong starter quickly.

Options: * Whole Wheat: 1. Bob's Red Mill, Organic Spelt Flour, Whole Grain, 20 oz (567 g) 2. Arrowhead Mills, Organic Whole Wheat Flour, Stone Ground, 22 oz (623 g) 3. Shtibel 6 100% whole wheat flour * Rye: 1. Bob's Red Mill, Organic Dark Rye Flour, Whole Grain, 20 oz (567 g)

2. Feeding the Sourdough Starter¶

Once the starter is established, the goal of feeding shifts from creation to maintenance and preparation for baking. The flour you use for feeding will directly influence the flavor and performance of your bread.

For a milder flavor and strong rise: Feeding with 100% Bread Flour will create a less sour-tasting loaf and provide the strongest gluten structure for your bread.
For a more complex, tangy flavor: Continuing to feed with a blend that includes Whole Wheat or Rye will maintain a more diverse microbial culture and add depth to the bread's flavor.

A great compromise is to feed the starter with mostly bread flour plus a small amount (10-20%) of whole wheat or rye. This gives the starter a consistent nutrient boost and flavor complexity while still maximizing the gluten potential for a well-risen loaf.

Options: * Bread Flour: 1. Pivetti Tipo Manitoba (Hebrew) - A high-protein flour ideal for providing structure to sourdough. 2. Maimon's Sourdough Flour - A strong flour (13% protein) with added sourdough cultures to enhance fermentation. 3. King Arthur Baking Company, Gluten Free Bread Flour, 2 lbs (907 g)

3. Making the Bread¶

Here, the primary goal is to bake the most nutritious loaf possible without creating a loaf that is too dense. Nutrition in flour comes from the bran and germ, which are only present in whole grains.

Therefore, the best choice is a blend of Whole Wheat and Bread Flour. Using 100% whole wheat flour will provide maximum nutrition but can be dense. By blending it with a strong Bread Flour, we can achieve a more open, pleasant crumb while still getting a significant nutritional benefit from the whole grain. A good starting point is 50% Whole Wheat Flour and 50% Bread Flour, which creates a delicious, nutritious, and structurally sound loaf.

Part 1: Cultivating Your Starter: A Scientific Approach¶

This guide is tailored to your ingredients and environment. The goal over the next week is to cultivate a stable, symbiotic culture of wild yeast and Lactic Acid Bacteria (LAB) that will leaven and flavor your bread.

Your Ingredients & Tools¶

Inoculation Flour: A 50/51 blend of Arrowhead Mills Organic Whole Wheat and Bob's Red Mill Organic Spelt.
Feeding Flour: Pivetti Tipo Manitoba Bread Flour.
Water: Dechlorinated or filtered water, warmed to approx. 24-26°C (75-78°F).
Container: Your 1-liter Weck Tulip Jar (rest the glass lid on top, without the seal or clips).
Digital Scale: For precision.

The Process (Day by Day)¶

Day 1: Inoculation¶

Action: In your Weck jar, mix 60g of your whole wheat/spelt blend with 60g of warm water. Stir thoroughly until no dry flour remains. Cover loosely and let it sit in a warm spot for 24 hours.
The Science: You are creating a welcoming environment for the wild yeasts and microorganisms present on the bran and germ of your whole-grain flours. This mixture serves as a rich food source to kickstart microbial activity.

Day 2: The Acidification Phase¶

Action: Do nothing. You may see a few bubbles or none at all. You might also notice a slightly funky smell. Let it rest for another 24 hours.
The Science: This is a critical waiting period. The initial microbes (often including Leuconostoc bacteria) begin to ferment the sugars in the flour, producing acids. This process lowers the mixture's pH. This acidic environment is crucial as it inhibits the growth of unwanted mold and spoilage bacteria, creating the perfect habitat for the acid-tolerant sourdough yeasts and lactobacilli we want to cultivate. Feeding now would dilute the acid and slow this process.

Day 3: First Feeding & Selection¶

Action: Discard all but 60g of the starter. To this, add 60g of your strong Pivetti Tipo Manitoba bread flour and 60g of warm water. Mix well.
The Science: The environment is now acidic enough to select for your desired microbes. By discarding, you remove waste products (like alcohol) and refresh the food supply. We switch to the high-protein Manitoba flour because its simple starches are easily digestible for the yeast, promoting vigorous production of CO2 gas—which is what will make your starter rise.

Days 4-7: Establishing a Rhythm (Twice-Daily Feedings)¶

Action: For the next few days, feed the starter every 12 hours. At each feeding, discard all but 60g of starter and feed it with 60g of Pivetti Tipo Manitoba and 60g of warm water.
The Science: This establishes a stable, symbiotic culture. The yeast consumes sugars to produce CO2 (rise) and ethanol. The Lactic Acid Bacteria (LAB) feed on sugars and the byproducts of yeast, producing the lactic and acetic acids that create the complex, tangy flavor of sourdough. This feeding schedule keeps the culture in its most active growth phase and strengthens it for baking.

Is It Ready for Baking?¶

Key Indicators: Your starter is ready when it predictably doubles or triples in volume within 4-8 hours of feeding. It will be full of bubbles and have a pleasant, tangy aroma reminiscent of yogurt or fruit.
The Float Test Explained: A spoonful of active starter floats because it is full of trapped CO2 gas from peak yeast fermentation. This demonstrates it has enough leavening power to make your bread rise. If it doesn't float, it simply needs a few more feeding cycles to gain strength.

Part 2: Baking Your Sourdough Loaf: A Science-Based Workflow¶

Once your starter is mature and active, you're ready to bake. This workflow is designed to maximize flavor development and achieve an open, airy crumb.

Your Recipe (Baker's Percentages)¶

This recipe creates a loaf with 50% whole grains and a hydration of 78%, which is a great starting point.

Leaven (Active Starter): 100g (20%)
Water: 375g (75%)
Pivetti Tipo Manitoba Flour: 250g (50%)
Whole Wheat/Spelt Blend: 250g (50%)
Fine Sea Salt: 10g (2%)

(Total Flour: 500g, Total Water: 375g)

The Process: A Two-Day Timeline¶

Day 1: Fermentation and Dough Development¶

Morning (e.g., 9:00 AM): Feed Your Starter * Action: Feed your starter as usual, but give it a bit more food: to 30g of starter, add 60g of Manitoba flour and 60g of water. * The Science: We are creating a "young" leaven. Using a larger feed ratio ensures the starter is at its absolute peak of yeast activity (and lower in acidity) when we mix the dough, which promotes a better rise.

Afternoon (e.g., 2:00 PM): Autolyse * Action: In a large bowl, mix the 375g of water with the 250g Manitoba flour and the 250g whole wheat/spelt blend. Mix until no dry flour remains. Do NOT add the starter or salt yet. Cover and let it rest for 1-2 hours. * The Science: This is the autolyse. It allows the flour to fully hydrate and kickstarts gluten development enzymatically, without any kneading. The protease enzymes begin to break down proteins, making the dough extensible and easier to work with later.

Afternoon (e.g., 4:00 PM): Final Mix * Action: Add 100g of your active starter and the 10g of salt to the dough. Use wet hands to dimple everything in, then squeeze and fold the dough for 3-4 minutes until fully incorporated. * The Science: We add the starter now to begin bulk fermentation. Salt is added last because it can tighten the gluten network and hinder the enzymatic activity of the autolyse.

Evening (e.g., 4:30 PM - 7:30 PM): Bulk Fermentation & Strength Building * Action: Let the dough ferment in a warm place for about 3-5 hours. During the first 1.5 hours, perform a set of "stretch and folds" every 30 minutes (3 sets total). * The Science: This is the primary fermentation where flavor develops. The yeast produces CO2, and the LAB produce acids. The stretch and folds build a strong and organized gluten network, which is essential for trapping the CO2 gas. Whole grain flours ferment faster, so watch the dough, not the clock. The dough is ready when it has increased in volume by about 30-50% (not doubled!) and shows bubbles on the surface.

Night (e.g., 8:00 PM): Shape and Cold Proof (Rétardation) * Action: Gently shape your dough into a tight ball (boule). Place it seam-side up in a floured proofing basket, cover it, and immediately put it in the refrigerator for 12-16 hours. * The Science: This is the cold proof, or rétardation. The cold temperature dramatically slows down the yeast's CO2 production but allows the LAB to continue working. This is where the complex, tangy sourdough flavors are developed. It also makes the dough firm and much easier to score and handle.

Day 2: The Bake¶

Morning/Afternoon: Baking * Action: 1. Place a Dutch oven in your oven and preheat it for 1 hour at 232°C (450°F). 2. Take the dough straight from the fridge. Flip it onto parchment paper, score the top with a lame or razor blade, and carefully place it in the hot Dutch oven. 3. Bake for 20 minutes with the lid on. 4. Remove the lid and bake for another 20-25 minutes with the lid off, until the crust is deep brown. * The Science: The intense heat from the preheated Dutch oven creates rapid "oven spring." The lid traps steam released from the dough, which keeps the crust soft initially, allowing the loaf to expand to its full potential. Removing the lid allows this steam to escape, and the dry heat then forms the crisp, caramelized crust through the Maillard reaction.

The Final, Crucial Step: Cooling * Action: Place the loaf on a wire rack and let it cool completely for at least 2-4 hours. * The Science: The bread is not finished baking when you take it out of the oven. The internal crumb is still setting as the loaf cools. Slicing into it too early releases steam and moisture, resulting in a gummy, dense texture. Patience here is essential for the perfect crumb.

Troubleshooting a "Stuck" Starter¶

Sometimes a starter can seem to plateau around days 4-8, with an unpleasant smell and little to no rise. This is almost always a solvable environmental or feeding issue.

Scenario 1: The Starter is Too Cold (Below 22°C / 72°F)¶

Symptoms: Sluggish, little activity, may smell a bit musty.
The Science: Yeast is less active at cooler temperatures, while some undesirable bacteria can still multiply.
The Fix: Find a warmer spot (24-26°C / 75-78°F), like an oven with the light on. Use slightly warmer water in your feedings to help kickstart yeast activity.

Scenario 2: The Starter is Too Warm (Above 27°C / 80°F) - Your Scenario¶

Symptoms: Very liquidy, a layer of dark liquid (hooch) on top, a strong "vomit" or acetone smell.
The Science: The starter is fermenting too quickly and running out of food long before the next feeding. This starvation phase produces excessive alcohol (hooch) and allows smelly bacteria to thrive.
The Fix:
1. Switch to a larger feeding ratio. Instead of 1:1:1 (starter:flour:water), move to a 1:2:2 or even 1:3:3 ratio. For example, keep 30g of starter and feed it with 60g flour and 60g water. This provides more food to last between feedings.
2. Use cool water. Using cool or even cold filtered water will help slow down the initial fermentation, giving the starter a longer, more stable period of activity.
3. Add a small amount of whole grain flour. A boost of 10% whole grain flour in the feeding can provide extra nutrients to help the yeast take over.

Sample Baker's Timeline¶

This is just an example to show how you can fit baking into a busy schedule.

Evening Bake:

8:00 AM: Feed your starter.
4:00 PM: Mix the dough (Autolyse).
5:00 PM - 7:00 PM: Perform stretch and folds.
7:00 PM - 11:00 PM: Bulk fermentation.
11:00 PM: Shape dough and place in the fridge for an overnight cold proof.
Next Day (Evening): Preheat oven and bake.

Morning Bake:

8:00 PM: Feed your starter.
Next Day 8:00 AM: Mix the dough (Autolyse).
9:00 AM - 11:00 AM: Perform stretch and folds.
11:00 AM - 4:00 PM: Bulk fermentation.
4:00 PM: Shape dough and do a final proof at room temperature.
6:00 PM: Preheat oven and bake.