Bread is OLD. Like…. really, really old.

The first loaf of bread was probably a happy accident that occurred when some yeast living on grains began to ferment while some dough for flatbreads – like matzo or crackers – was being made. We know that neolithic farmers made bread 10,000 years agoThe first recorded yeast bread was made by Egyptians 4,000 years ago. Bread was so important to the Egyptians that you can even find it in their tombs – the most famous of which is the tomb of Tutankhamun where archaeologists have found loaves of bread with coriander added to them.

Leavened bread is now a staple in almost every culture on Earth. Bread is inexpensive, nutritious, delicious, portable and easy to share. Anywhere on the planet where wheat, rye or barley could be grown in sufficient quantities, bread became the basic food in most people’s diet. It has been called the “staff of life.”

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AN INTRODUCTION TO YEAST BREADS

What makes most of the breads we know and love different from flatbreads, baked porridges, and quickbreads is yeast.

Yeast is a magical change-agent that turns milk into cheese, cabbage into sauerkraut, vegetables into kimchi, and pepper mash into hot sauce. Even cocoa beans and olives rely on yeast to lose their natural bitterness and go from the plantation to your plate! For the purposes of this post, we are going to talk at some length about the most common use of yeast in the kitchen: breadmaking.

Why are we going to talk about yeast so much?

There’s a lot you need to know to use yeast effectively in your baking – there’s basic science concepts to nail down, a working knowledge of these is sufficient – no need to become an organic chemist! We’ll seek to understand the yeast organism itself so that we use it correctly, consistently. We’ll look into how it ferments, it’s market forms, how it is stored, how it is tested for effectiveness, and so on. To bake yeast breads RIGHT there’s a lot to understand that recipes don’t explain – stuff that is UNDER the surface. Think of breadmaking like an iceberg: what you need to know UNDERNEATH the recipe is much greater than the surface instructions on the page.

But before we dive into the glorious world of yeast and fermentation and hydration and gluten….

Let’s talk about yeast breads in general. This is for YOU, my wonderful culinary 2 & 3 students: you need to know the basics before we get into the particulars.

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Some folks may already be feeling a little lost. In that case, better review the basics you learned in Culinary 1. Here’s a link to a post that should help:

Getting to know the Eight Ingredients Bakers Use Everyday

Back? Good. Now that you are comfortable with the basics, read on…

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2 TYPES OF YEAST BREAD

In its simplest form, all yeast doughs are a mixture of flour, liquid, and yeast. The base dough is then divided into two broader categories: lean doughs and rich doughs.

Lean doughs are made with only flour, yeast, water, and salt. They have very little or no sugar or fat. Breads made from lean dough tend to have a chewy texture and a crisp crust. French bread and hard rolls are examples of lean doughs. Rich or Enriched doughs are made with the same ingredients as lean doughs, but with the addition of shortening or tenderizing ingredients such as sugars, syrups, butter, eggs, milk, and cream. Introducing these ingredients changes the bread’s overall texture, as well as the way the dough is handled. Rich doughs have a cake-like texture after baking. Parker House rolls, cloverleaf rolls, soft rolls, and Danishes are examples of rich doughs.

There is a third kind of bread: sourdough. Sourdough is made from wild yeast, caught from flour and the air and “fed” until it is active enough to serve as a leavener. The wild yeast gives the bread made from it a different flavor profile depending on where it is “caught.” Some sourdough yeasts cultures are famous for their interesting, tangy, and slightly sour taste – San Francisco and Southern Italy are particularly famous for their sourdoughs.

2 METHODS OF MAKING BREAD

Bakers use two primary methods to make yeast breads: the straight- dough method and the sponge method.

The straight-dough method (also called straight, straight-mix, or bulk method) can be used for all types of yeast dough. When using the straight-dough method to mix dough, the baker combines all ingredients at the same time when using instant yeast, OR activates the yeast separately with 100°F-120°F water until it starts to bubble, THEN adds all the rest of the ingredients (if using active or fresh/cake yeast).

Here’s something important you should know: Yeast begins to die at around 120°F and is completely killed at 140°F. So don’t add really hot water or put your rising dough in a 140°F proofing box. You’ll kill the yeast and make a disgusting cracker. Dead yeast will not leaven bread and will make the flavor of your product taste like stale, nasty beer.

After mixing the water, yeast, sugar, salt, and flour, the baker kneads the dough until it is elastic and smooth. In its simplest terms, kneading is the process of preparing dough by combining a mixture of flour, water, yeast and other ingredients, either with your hands or a stand mixer fitted with a hook attachment. As a result, gluten develops in the dough, giving the final product the stretch and texture you want.

The second way bakers make bread is by using the sponge method. To do this, bakers add ALL the yeast, half of the liquid, and half of the flour to make a thick batter called a sponge. After the sponge rises and doubles its size, the remaining fat, liquid, salt, sugar, and flour are added. The dough is then kneaded and left to rise. Breads made with the sponge method have a lighter texture and more unique flavor than breads made using the straight-dough method.

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Before we go any further, lets dive into an overview of the process and the specialized terms used to describe each step. These are the 9 distinct steps used to make ALL yeast breads.

1. Scaling: this is simply the process of carefully measuring ingredients. It’s called “scaling” because in some old-school classic bakeries, professional bakers still use a mechanical scale – a dual platform piece of equipment with a adjustable poise and beam with counterweights for calibration. Nowadays, most professional bakers use the much more consistent and accurate digital scale to weight ingredients.
2. Mixing and kneading: Mixing combines the ingredients, distributes the yeast, and develops the gluten. Kneading further develops the gluten and makes the dough smooth and elastic.
3. Fermentation/ first proof/ pushing up: During fermentation, the yeast acts on sugars and starches in the dough to produce carbon dioxide, flavor compounds, and alcohol. In the process of the yeast “eating” the sugars, carbon dioxide gas gets trapped in the gluten. This step is also known as “pushing up” or the “first proof” and can take 60 minutes to 2 hours depending on the warmth of the product and how rich the dough is.
4. Punching down: After the dough has doubled in size, the dough is gently folded down to expel and redistribute carbon dioxide gas pockets that have formed in the dough. Punching also relaxes the gluten and redistributes the yeast evenly.
5. Portioning: The dough is divided into pieces of uniform weight and size according to whatever final product that is desired. Uniformity is important and the only way to do that is to use a portion scale to ensure every piece is the same.
6. Rounding/ shaping: The dough is shaped into smooth, round balls (when rounding) or formed into other shapes depending on what the final loaf should look like. During rounding or shaping, the outside layer of gluten becomes smooth, which holds in the gases.
7. Proofing – Right before putting the loaf into the oven, the shaped dough is allowed to rise a second time, usually until almost doubled in size. The danger at this step is in over-proofing, in which all the available sugars are “eaten” by the yeast and the dough collapses.
8. Baking – obviously. Put it in the oven. During the initial heat, the bread rises a last time as the CO2 expands and the surviving yeast goes into overdrive. Once the outside of the dough hits 180*F, the gluten structure stabilizes and the dough achieves its final form. All breads are done baking when they read 185 – 210*F on a probe thermometer inserted into the middle of the product. Rich doughs are done at cooler temperatures; lean doughs require higher temperatures.
9. Cooling and storing: Tenth and final step in making yeast breads. The finished bread is removed from the pan and placed on a rack to allow air circulation, cooling at room temperature. After it is thoroughly cooled, the bread is wrapped in a moisture-proof bag so that it will not become stale . You can FREEZE baked products for longer term storage. NEVER, EVER store bread in the refrigerator – instead hold in a cooler spot of the house at room temperature.

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There are three things which need further explanation do have a solid grasp of the fundamentals of breadmaking:

• Developing gluten / kneading
• The four types of yeast and their uses
• Fermentation control through temperature control

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Yeast is a single-celled living organism in the fungus family. There are more than 1,500 species of them on Earth. While each individual yeast is only one cell, they are surprisingly complex and contain a nucleus, DNA and many other cellular parts found in more complicated organisms.

Yeasts break down complex molecules into simpler molecules to produce the energy they live on. They can be found on most plants, floating around in the air and in soils across the globe. Quite a number of these yeast species can convert sugar into carbon dioxide and alcohol – a really valuable quality humans have been using to their benefit for millennia – but only twenty-four of them make foods that actually taste good. Of these 24 – only one species is used to make bread: Saccharomyces cerevisiae, which literally means “sugar-eating fungus.” This is bread yeast, the yeast we humans know and love.

Here’s how it works: the process starts out the same whether you are making bread or beer! Enzymes in the yeast convert sugar into alcohol, carbon dioxide, and flavor compounds. With bread, a baker wants to capture the carbon dioxide to leaven the bread and make it rise. With beer, a brewer wants to capture the alcohol (and the bubbles).

When you mix yeast with a bit of water and flour, the yeast “wakes up” and begins to eat the long chains of carbohydrates found in the flour called starches. When yeast breaks down starch, it produces carbon dioxide gas, ethyl alcohol, and flavor compounds. The CO2 is trapped in the dough by stringy protein strands called gluten and causes the dough to rise. After baking, those little air pockets are locked into place and result in airy, fluffy bread.

But soft bread is not the only result. When yeast break down the starches in flour, it create another byproduct: flavor compounds in the form of delicious, caramelized sugars. The longer you let the dough rise, the stronger these good flavors will be, and some of the most popular bread recipes use this to their advantage.

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Different types of yeast

ACTIVE DRY

• Description: This yeast is a dry, granular form of baker’s yeast with a protective coating. The drying process kills about a quarter of the yeast cells, and the dead cells coat the live ones. 
• Key Characteristics:
  • Activation (Proofing): Requires proofing—dissolving in warm water (105–110°F) with a pinch of sugar—to rehydrate the live cells and activate them before adding to the other ingredients. The resulting foam also serves as proof that the yeast is alive.
  • Speed: Starts more slowly than instant yeast but, in longer rise times (2–3 hours), it will catch up.
  • Flavor: Tends to produce a slightly more “yeasty” or moderate flavor profile than instant yeast.
  • Shelf life: Much longer than fresh yeast. An unopened packet can last up to two years, while an opened one stored in the refrigerator should be used within four months.
  • Best uses: A versatile, all-purpose yeast suitable for most home baking, including sandwich bread, rolls, and pizza dough. The proofing step offers a chance to check that the yeast is active before committing to the full recipe. 

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INSTANT YEAST

• Description: Also a dry, granular yeast, but milled into finer particles than active dry yeast. It is more porous, allowing it to absorb liquid and activate more quickly. Some varieties are specifically labeled as “RapidRise” or “Bread Machine Yeast” for even faster fermentation. 
• Key characteristics:
  • Activation: Does not require proofing. It can be mixed directly with the dry ingredients and begins working almost immediately.
  • Speed: The fastest-acting yeast, which significantly shortens the dough’s rise time.
  • Flavor: Produces a milder, less pronounced yeast flavor compared to fresh or active dry yeast. It does not allow for a long, slow flavor development.
  • Shelf life: The most stable of the three. Unopened packages last up to two years, and opened packages can last up to six months in the refrigerator or freezer when properly stored.
  • Best uses: Ideal for recipes where a quick rise is desired, such as cinnamon buns, quick rolls, and some pizza doughs. It is the best choice for bread machine recipes. 

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FRESH OR CAKE YEAST

• Description: Also known as cake or compressed yeast, fresh yeast is a moist, pale block of living yeast cells that feels like a soft, crumbly clay. 
• Key characteristics:
  • Best uses: Ideal for high-hydration or soft doughs, such as those for brioche and other enriched breads. It is also favored for long-fermentation artisan breads due to its flavor profile. 
  • Activation: Must be dissolved in a small amount of lukewarm liquid (typically from the recipe) before use to ensure it is active.
  • Speed: Very active and reliable when fresh, producing a rapid rise.
  • Flavor: Gives baked goods a distinct, rich flavor that many professional bakers prefer.
  • Shelf life: Highly perishable. Must be refrigerated and used within about two weeks. It should not be frozen.

Sourdough starter: A living culture of wild yeast and bacteria. It provides a distinct tangy flavor and acts as a leavening agent. Sourdough starters and making sourdough breads are significantly outside the scope of an introduction. For the ambitious, sourdough can be a fun adventure (though frequently frustrating). Read THIS for a primer.

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In baking, fermentation is defined as the metabolic process by which yeast consumes the naturally occuring sugars and starches in dough, producing ethanol (alcohol), carbon dioxide, which causes the dough to rise by creating air pockets, and flavor compounds, contributing to flavor and aroma. Fermentation is an anaerobic process, meaning it occurs without oxygen. During this process, gluten develops and relaxes, enhancing the dough’s structure and texture.

Hopefully it is obvious that the fermentation stages are the most important things that happen during breadmaking. And the most powerful tool in the baker’s toolbox—especially when working with sourdough—isn’t a special oven or an ancient starter or specialized techniques. It’s fermentation control. And we control fermentation by controlling temperature.

Temperature plays a HUGE role in how dough ferments, how it rises, and ultimately, how your bread is going to taste. There are two approaches to fermentation: warm and cold. Both have their pros and cons… let’s look at them both.

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The Role of Warm Fermentation

Warm fermentation typically happens at temperatures above room temperature—often in the 78–82°F range. Within this range, yeast activity increases significantly, consuming sugars faster, producing more gas, and accelerating the dough’s rise.

Note: when you ferment ALL your dough at the same time, it is called a “bulk ferment” because you are fermenting all the dough at the same time, you know… in “bulk.”

Because warm fermentation speeds everything up, it requires a bit more vigilance. A dough fermenting at 80°F might hit its target rise in just 60-90 minutes. If it goes too far, it risks overproofing—where the yeast eats all the available sugars and then starves to death. As a result, the dough structure collapses, leading to dense, gummy, disgusting loaves. To avoid this, recipes that use warm fermentation often suggest stopping the bulk ferment at a lower percentage rise—around 30% is a common target. This leaves room for continued fermentation during later stages like shaping and resting.

Measuring dough temperature—not just room temperature—is crucial here. Dough straight from mixing is often cooler than the air around it, and that internal temperature is what determines how the microbes behave. Using a thermometer helps take the guesswork out of timing and ensures more consistent results.

The Power of Cold Fermentation

Cold fermentation, sometimes called cold retardation, works in the opposite way. The dough is placed in the refrigerator, usually below 40°F, to deliberately slow down the fermentation process. Sometimes you do this because you want the dough ready for baking on the following or subsequent day. Sometimes you might use a cold ferment to really develop flavor and increase a sourdough-like taste. Whatever the reason, there a a number of reasons to choose this method.

At cooler temperatures, yeast activity nearly stops, but lactic acid bacteria naturally present in the dough keep right on working—just much more slowly. That extended activity leads to deeper, more complex flavors, especially those tangy, sour notes often associated with artisan sourdough. Time becomes the secret ingredient, allowing aromatic compounds to develop that simply can’t form in a faster, warm ferment.

This method also offers flexibility. Once the dough is in the fridge, the window for baking stretches dramatically. You don’t need to bake at a precise time. The dough can often sit chilled for 24 to 72 hours, with some bakers pushing it even further to achieve extra sourness.

That said, cooling isn’t instant. After putting dough in the fridge, it can take several hours for the core temperature to fully drop. Fermentation continues during this transition, just at a decelerating pace. That means dough still needs to be monitored, especially in those first few hours.

Many recipes that incorporate a long cold ferment will encourage a higher rise during the initial warm bulk phase—sometimes 50% or more—before chilling. This gives the dough a head start before the yeast activity slows down in the fridge.

Comparing the Two

Both warm and cold fermentation have their strengths:

• Speed: Warm fermentation is faster and ideal when you want fresh bread on the same day.
• Flavor: Cold fermentation offers a broader and deeper flavor profile, especially for sourdough lovers.
• Flexibility: Cold fermenting gives bakers MUCH more control over timing, fitting around busy schedules more easily.
• Risk of Overproofing: There is a danger of overproofing with warm fermentation if not watched closely. Cold methods slow everything down and reduce that risk, although very long cold proofs can eventually break down gluten structure if taken too far.

Ultimately, choosing between warm and cold fermentation depends on your goals. Are you after a quicker bake or more complex flavor? Do you have time to tend the dough closely, or do you need to stretch the process out over a couple of days?

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Curious if you got it right? Here’s a handy measuring stick to gauge how well you fermented your dough:

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Breadmaking is a fascinating art and a challenging science. You can go much further… there are preferments, laminates, and many more methods of developing gluten than we have even hinted at! But understanding these basics will hopefully make your first few loaves a lot more tasty and give you enough knowledge to know if something is going wrong long before your dough hits the oven.