Course outline
Module 1
Module 1: Sourdough Foundations
Sourdough Foundations
Knowledge check
Q1. What are the two basic ingredients needed to make a simple sourdough starter?
- A. Yeast and sugar
- B. Flour and water ✓
- C. Baking soda and milk
- D. Eggs and butter
Why: A sourdough starter is made by mixing flour and water, which allows wild yeast and lactic acid bacteria from the environment and the flour to colonize the mixture and ferment it over several days.
Q2. What does the term 'levain' refer to in sourdough baking?
- A. A type of bread pan
- B. A mature starter used to leaven dough ✓
- C. A scoring pattern on loaves
- D. A commercial yeast packet
Why: Levain is the French term for a mature sourdough starter that has been fed and is at peak activity, which is then mixed into the dough to leaven it.
Q3. Why is a sourdough starter sometimes described as being 'at its peak'?
- A. When it has been refrigerated for a month
- B. When it has doubled in volume and is full of bubbles after feeding ✓
- C. When it turns completely black
- D. When it has been dried into flakes
Why: A starter is at peak when it has roughly doubled in size after a feeding, is bubbly and domed on top, and has the strongest leavening power to raise dough.
Q4. What is the purpose of 'feeding' a sourdough starter?
- A. To kill unwanted bacteria completely
- B. To provide fresh flour and water so the yeast and bacteria stay active ✓
- C. To cool the starter down before baking
- D. To add salt for flavor
Why: Feeding replenishes the flour and water that the microorganisms consume, keeping the yeast and lactic acid bacteria healthy and active so the starter remains capable of leavening bread.
Q5. What does a sour, tangy smell in a starter generally indicate?
- A. The starter has gone bad and must be discarded
- B. Lactic and acetic acids are being produced by the bacteria, which is normal ✓
- C. The starter has too much salt
- D. The starter is frozen
Why: The tangy flavor comes from lactic and acetic acids produced by lactic acid bacteria and yeast during fermentation, and it is a normal, desirable characteristic of a healthy sourdough starter.
Module 2
Module 2: Wild Yeast and Starters
Wild Yeast and Starters
Knowledge check
Q1. What is the main microorganism responsible for leavening a sourdough starter?
- A. Saccharomyces cerevisiae, a commercial baker's yeast
- B. Wild yeasts naturally present in flour and the environment ✓
- C. Bacillus subtilis, a common soil bacterium
- D. Penicillium mold spores introduced during mixing
Why: A sourdough starter is cultivated from wild yeasts and lactic acid bacteria that naturally occur on flour and in the environment, rather than from added commercial yeast.
Q2. Why is it recommended to feed a starter with fresh flour and water on a regular schedule?
- A. To remove the starter's acidity completely
- B. To supply new food so the yeast and bacteria stay active and balanced ✓
- C. To cool the starter down before baking
- D. To prevent the starter from ever rising
Why: Regular feedings provide fresh carbohydrates and nutrients, keeping the yeast and lactic acid bacteria healthy and active so the starter stays vigorous and predictable.
Q3. What is a common sign that a starter is ready to use in a bake?
- A. It has a clear, watery appearance with no bubbles
- B. It has doubled or more in volume and is full of bubbles ✓
- C. It smells like rotten eggs and has a grey colour
- D. It has separated into a solid block with no movement
Why: A healthy, active starter typically doubles in volume within a few hours of feeding and is full of bubbles, indicating that yeast fermentation is at its peak.
Q4. What does the liquid 'hooch' that sometimes forms on top of a starter indicate?
- A. The starter has been contaminated and must be thrown away
- B. The starter is hungry and has run low on food ✓
- C. The starter has been stored in too warm a place
- D. The yeast has been killed by excessive stirring
Why: Hooch is alcohol produced when the starter exhausts its food supply. It is generally harmless and simply signals that the starter needs feeding, though it can be poured off or stirred back in.
Q5. Which factor most directly affects how quickly a starter ferments?
- A. The colour of the storage jar
- B. The ambient temperature of the environment ✓
- C. The brand name printed on the flour bag
- D. Whether the starter is stirred with a metal or wooden spoon
Why: Yeast and bacteria are highly sensitive to temperature. Warmer conditions speed up fermentation significantly, while cooler conditions slow it down.
Module 3
Module 3: Flour Selection and Hydration
Flour Selection and Hydration
Knowledge check
Q1. Which flour type is most commonly recommended for beginners making sourdough bread because of its balance of protein and availability?
- A. Cake flour
- B. Bread flour ✓
- C. Self-rising flour
- D. Pastry flour
Why: Bread flour has a higher protein content (typically around 12-14%), which develops strong gluten networks that trap the gas produced by fermentation, giving sourdough its structure and open crumb.
Q2. What does 'hydration' refer to in sourdough baking?
- A. The temperature of the kitchen
- B. The ratio of water to flour in a dough, expressed as a percentage ✓
- C. The amount of salt added to the dough
- D. The length of time the dough rests
Why: Hydration is calculated by dividing the weight of water by the weight of flour and multiplying by 100. A 75% hydration dough contains 75 grams of water for every 100 grams of flour.
Q3. Why might a beginner start with a lower hydration dough, such as 65-70%?
- A. Low hydration doughs never rise
- B. Lower hydration doughs are easier to handle and shape, making them more forgiving for beginners ✓
- C. Lower hydration doughs require no fermentation
- D. Lower hydration doughs always produce larger holes in the crumb
Why: Stiffer doughs hold their shape better and are less sticky, which makes folding, shaping, and scoring more manageable while learning the technique.
Q4. What effect does whole wheat flour have on water absorption compared to white flour?
- A. It decreases the amount of water the flour absorbs
- B. It has no effect on water absorption
- C. It increases the amount of water the flour absorbs because of its bran and germ ✓
- D. It makes the flour completely impermeable to water
Why: Bran and germ particles in whole wheat flour are thirsty and absorb more water than refined white flour, so doughs made with whole wheat often need additional hydration.
Q5. If a recipe calls for 500 g of flour and 350 g of water, what is the hydration percentage?
- A. 50%
- B. 60%
- C. 70% ✓
- D. 75%
Why: Hydration is water weight divided by flour weight times 100: (350 / 500) x 100 = 70%.
Module 4
Module 4: Mixing, Folding, and Gluten Development
Mixing, Folding, and Gluten Development
Knowledge check
Q1. What is the primary purpose of mixing flour and water during the initial stage of sourdough bread making?
- A. To kill any wild yeast present in the flour
- B. To hydrate the flour so gluten can begin to form
- C. To remove bran from the flour
- D. To raise the dough temperature before fermentation
Why: When flour meets water, the proteins glutenin and gliadin begin to link together into gluten. Without hydration, these proteins cannot form the network that traps gas and gives bread its structure.
Q2. What does a 'folding' motion accomplish during sourdough dough development?
- A. It cools the dough so fermentation slows down
- B. It adds extra salt evenly throughout the dough
- C. It strengthens gluten by stretching and aligning the protein strands without overworking the dough
- D. It separates the dough into smaller portions for shaping
Why: Folding gently stretches the dough and realigns gluten strands, building strength gradually. Unlike aggressive kneading, it develops structure while keeping the dough extensible and preserving gas bubbles.
Q3. Why is an autolyse rest often used before adding salt and starter to sourdough dough?
- A. It allows the starter to multiply to double its size
- B. It lets the flour fully hydrate and begin gluten development with less mechanical work
- C. It kills unwanted bacteria before fermentation begins
- D. It warms the dough to the ideal proofing temperature
Why: During autolyse, flour and water rest together for 20 to 60 minutes. Enzymes break down starches and proteins begin bonding on their own, so less kneading is needed and the dough becomes more extensible.
Q4. How can a baker tell when gluten development is sufficient in sourdough dough?
- A. The dough turns a deep golden color
- B. The dough becomes smooth, elastic, and holds its shape better, passing the windowpane test
- C. The dough sinks when placed in a bowl of water
- D. The dough doubles in volume during mixing
Why: A well-developed dough feels smooth and springy, and it can be stretched thin enough to see light through without tearing, known as the windowpane test. Color and volume are not reliable indicators at this stage.
Q5. What is the main risk of overmixing sourdough dough during the mixing stage?
- A. The dough will not rise at all during bulk fermentation
- B. The gluten can become overly tight and the dough can tear, turn sticky, or lose extensibility
- C. The starter will become inactive and stop producing gas
- D. The bread will taste too sour
Why: Excessive mechanical work over-tightens the gluten network, making the dough tough, tearing easily, and paradoxically becoming slack and sticky as the structure breaks down. Gentle mixing with rest periods avoids this.
Module 5
Module 5: Fermentation and Timing
Fermentation and Timing
Knowledge check
Q1. What is the main purpose of a sourdough starter in bread making?
- A. To add sweetness to the dough
- B. To leaven the dough using wild yeast and lactic acid bacteria ✓
- C. To thicken the dough so it holds its shape
- D. To replace salt as a flavor enhancer
Why: A sourdough starter is a culture of wild yeast and lactic acid bacteria that ferments flour and water, producing carbon dioxide to raise the dough and organic acids that give sourdough its characteristic tang.
Q2. What does it mean when a sourdough starter is said to be 'at its peak'?
- A. It has stopped producing any gas
- B. It has fully risen and is about to begin collapsing ✓
- C. It has turned dark brown and sour
- D. It has been refrigerated for over a week
Why: A starter at its peak has risen to its maximum volume, often doubling or more, and is full of active yeast. Using it at this point gives the best leavening power. Waiting too long means it begins to collapse and lose strength.
Q3. Why does a longer bulk fermentation at cooler temperatures often develop more flavor?
- A. Cooler temperatures kill the yeast, which concentrates flavor
- B. Slow fermentation gives bacteria more time to produce acids and complex flavor compounds ✓
- C. Cold dough absorbs more salt
- D. Warm dough always becomes bitter
Why: At cooler temperatures yeast activity slows more than bacterial activity, so acid and flavor compounds build up over a longer period. This is why cold retarding in the refrigerator is popular for developing tangy, complex loaves.
Q4. What is a reliable sign that bulk fermentation is complete?
- A. The dough has been sitting for exactly four hours
- B. The dough has grown roughly 50 to 75 percent in volume and looks airy with bubbles on the surface ✓
- C. The dough has turned completely white
- D. The dough sinks immediately when placed in water
Why: Bakers typically look for a volume increase of about 50 to 75 percent, with visible bubbles and a jiggly, airy texture. Clock time varies with temperature and starter strength, so visual and tactile cues are more reliable than a fixed timer.
Q5. What happens if a sourdough loaf is over-proofed?
- A. It becomes extra crusty and golden
- B. The gluten structure weakens and the loaf may spread flat and lose oven spring ✓
- C. The loaf automatically gains more salt
- D. The yeast becomes dormant permanently
Why: Over-proofing exhausts the food supply and weakens gluten, so the dough cannot trap gas well. The result is a flat, dense loaf with poor oven spring and sometimes a gummy crumb.
Module 6
Module 6: Shaping and Scoring
Shaping and Scoring
Knowledge check
Q1. What is the main purpose of shaping a sourdough loaf before the final proof?
- A. To add color to the crust
- B. To build surface tension so the dough holds its structure and rises upward ✓
- C. To remove all the air from the dough
- D. To activate the wild yeast for the first time
Why: Shaping creates a tight outer skin of surface tension, which helps the loaf hold its form and rise upward in the oven instead of spreading out.
Q2. Why should you score sourdough before baking?
- A. To make the bread taste more sour
- B. To release steam and control where the loaf expands in the oven ✓
- C. To help the dough cool down faster
- D. To prevent the crumb from becoming moist
Why: Scoring creates a controlled weak point, allowing the loaf to expand (oven spring) in a predictable place and preventing random bursting along the sides.
Q3. What is the recommended angle for holding a lame (scoring blade) when scoring sourdough?
- A. Straight up and down, 90 degrees to the dough
- B. Flat, almost parallel to the surface
- C. About 30 degrees to the surface ✓
- D. Upside down with the blade pointing away
Why: Holding the blade at roughly 30 degrees lets it cut cleanly under the skin, creating an ear or opening that expands nicely during baking.
Q4. Which tool is most commonly used to score sourdough loaves?
- A. A butter knife
- B. A lame or sharp razor blade ✓
- C. A wooden spoon
- D. A pastry brush
Why: A lame or a very sharp razor blade gives a clean, shallow cut without dragging the dough, which is essential for a good score.
Q5. What is a good sign that your dough is properly shaped and ready to be scored?
- A. The surface is dry, cracked, and flaky
- B. The surface feels smooth and taut, and the dough holds its shape ✓
- C. The dough is sticky and spreads when left on the counter
- D. The dough has large bubbles breaking through the surface
Why: A smooth, taut surface that holds its shape indicates good surface tension, which means the loaf is ready to score and bake without collapsing.
Module 7
Module 7: Baking for Crust and Crumb
Baking for Crust and Crumb
Knowledge check
Q1. What is the main purpose of preheating a Dutch oven before baking sourdough bread?
- A. To soften the dough so it spreads more evenly
- B. To create an intense initial burst of heat that promotes oven spring and a crisp crust ✓
- C. To activate the wild yeast before the dough is shaped
- D. To cool the surface of the dough so it does not over-brown
Why: A preheated Dutch oven delivers strong, immediate heat to the dough. This sudden heat drives rapid oven spring (the final rise in the oven) and helps the crust set and crisp, while the trapped steam keeps the surface soft long enough for the loaf to expand.
Q2. Which factor most directly influences how open and airy the crumb of a sourdough loaf becomes?
- A. The color of the flour bag
- B. Hydration level and the development of gluten and gas structure during fermentation ✓
- C. The shape of the loaf before scoring
- D. Whether the loaf is cooled on a rack or on a cutting board
Why: Higher hydration dough, combined with good gluten development and proper fermentation, traps more gas and produces larger, more open holes in the crumb. Shaping and cooling affect other aspects of the loaf but not the internal structure as directly.
Q3. Why do bakers score the top of a sourdough loaf before baking?
- A. To make the loaf easier to slice after cooling
- B. To release strain in the dough so it expands in a controlled place rather than tearing randomly ✓
- C. To let excess moisture escape from the center of the loaf
- D. To add decorative patterns that help the loaf brown evenly
Why: Scoring creates a weak point in the skin, allowing the loaf to expand predictably during oven spring. Without scoring, the dough tends to burst at its weakest spots, which can look uneven and affect the final shape.
Q4. What does a thick, deeply browned crust usually indicate about a sourdough bake?
- A. The dough was underproofed and needs more time
- B. The bread was baked at a suitable temperature for a long enough time to develop flavor through caramelization and the Maillard reaction ✓
- C. The starter was too young to produce enough acid
- D. The flour contained too little protein
Why: Browning comes from the Maillard reaction and caramelization of sugars at high temperatures. A deep, flavorful crust reflects good oven heat and adequate bake time, and it contributes much of the characteristic taste of sourdough.
Q5. After a sourdough loaf comes out of the oven, why should you let it cool fully before slicing?
- A. Cutting warm bread causes the crust to lose all its flavor
- B. The crumb is still setting, and slicing too early can cause a gummy texture and compressed interior ✓
- C. Warm bread cannot be stored in a bread bag
- D. Bread must sit overnight for the yeast to die off
Why: As the loaf cools, the starches and proteins in the crumb finish setting and the moisture redistributes. Slicing too soon releases steam and leaves the interior gummy and dense, even though the loaf looked fully baked.