Sourdough vs Yeast: What’s the Difference?

Both yeast and sourdough starter play an important role in many bakers lives. Depending on what type of bread you intend to bake. Some bakers may prefer to use one over the other, whilst others like to experiment with each separately. But what’s the difference between the two, and is one better than the other? Let’s find out!

What is Yeast?

Yeast is a single-cell organism that requires food, warmth, and moisture to live. Its main purpose is to convert its food – sugar, and starch – through fermentation – into carbon dioxide and alcohol. The presence of carbon dioxide is what ensures the perfect bread rise.

Types of Baker’s Yeast

Typically, 3 types of commercial yeast aim to leaven the dough in any bread-baking recipe. Each type of yeast has its distinct properties and flavors, which can determine the type of commercial yeast you may choose to include in your bread recipe.

These varieties of commercial yeast include:

• Active dry yeast
• Fresh yeast
• Instant yeast

Active Dry Yeast

Active dry yeast harbors a grainy consistency and must be activated in water or milk before it is added to a recipe.

This type of yeast is best when used in recipes that require a lengthy fermentation process; great for bread dough recipes that require a double rise and longer proofing time.

Fresh Yeast

Fresh yeast is also known as “cake yeast”. It is sold in thick white blocks that must be refrigerated.

Fresh yeast is best added to sweet bread and donuts, although it can also be used in any recipe that requires yeast such as bread, pizza, or dinner rolls.

Instant Yeast

Instant yeast is a type of dry yeast that offers a rapid rise; often used by home bakers.

The best part is that it can be deposited directly into your dough, although you must remember to add a small amount of water to encourage activation.

What is a Sourdough Starter?

Sourdough starter is a type of leavening agent that also helps baked goods rise. However its complex flavor, and liquid form is what sets it apart from commercial yeast.

Sourdough starters are made by combining flour and water that must be left unrefrigerated to be inhabited by wild yeasts and bacteria. A small portion of the starter must be discarded before every feed, to avoid the appearance of mold. The remaining starter must be fed with fresh flour and water.

One of the main characteristics that set sourdough apart from commercial yeast is the fact that your starter is essentially alive and thriving. It must be looked after, fed regularly, and closely monitored before it is ready to be used in your sourdough recipes.

The inclusion of sourdough starter in your dough is what ensures a good rise, perfect crust, and a flavorful loaf.

How is Sourdough Starter Made?

A bubbly sourdough starter is created through the inclusion of flour and water. Feed the starter for 5 days with equal parts flour and water, then it’s ready to use in your sourdough bread.

Day 1

To make your starter combine 50g of flour with 50g of water in a jar or plastic container. Ensure the flour is well incorporated, without any visible lumps and bumps in the mixture. Leave this to rest – uncovered – at room temperature for 24 hours.

Day 2

Discard half of the mixture, then combine 50g of water and 50g of flour into yesterday’s mixture, stirring thoroughly. Ensure the flour is well incorporated then lightly cover with a tea towel and let this rest at room temperature for another 24 hours.

Day 3

Repeat yesterday’s process and remember to leave the mixture to rest at room temperature for 24 hours.

Day 4

You should notice some visible activity in the mixture. Bubbles will gather at the sides and top of the mixture. Add 50g flour and 50g of water into the mixture, stirring till thoroughly combined, then leave this semi-uncovered at room temperature for 24 hours.

Day 5

The mixture should be very active by now, and ready for making your starter. If the mixture isn’t bubbling, continue to feed it after 24 hours until it does. Once it’s ready it will impart a pleasant yogurt-like smell. Keep this refrigerated and once you’re ready to use it, discard half and feed it with 100g of flour and 100g of water. Leave this at room temperature and it should be activated once again.

How is Yeast Different to Sourdough Starter?

Although sourdough starter is different from commercial yeast, it doesn’t mean that it is completely void of yeast. In truth, a sourdough starter is a mixture brimming with naturally occurring yeasts.

The main difference between yeast and sourdough starters is the time taken to leaven bread. Since commercial yeast has been fabricated in a certain way, it can rise bread quickly, whereas a sourdough starter can take many hours or days to rise bread.

However, with the difference in time, there is a difference in flavor. Therefore, the time it takes the wild yeast in your sourdough starter to rise your dough will contribute to its unique tart flavors.

This is mainly due to the cold fermentation process that gradually encourages the expansion of acetic acid, which increases the sourness of sourdough bread.

Is it Better to Use Yeast or Sourdough Starter?

Whether you choose to use commercial yeast or a sourdough starter in bread baking, will rely on what you’re planning to achieve from your bake. There are many pros and cons concerning the use of both baker’s yeast and sourdough starters in bread recipes.

For instance, yeast produces a rapid dough rise to ensure a quick bake, whilst a sourdough starter requires patience to produce a delicious flavorful bread.

Though flavor can be important, often we find ourselves short of time and resources, therefore having to opt for yeast bread.

Let’s take a look at some of the pros and cons concerning sourdough starters and commercial yeast.

Pros and Cons of Commercial Yeast

Pros	Cons
Bread dough can be baked on the same day	Commercial yeast is manufactured and processed.
Requires less time for the dough to rise	Lacks depth of flavor and taste.
Easy to find at local grocery stores	Doesn’t provide the same health benefits as sourdough bread.

Pros and Cons of Sourdough Starter

Pros	Cons
Has a variety of health benefits	Sourdough starter requires many hours or days for the dough to rise and proof. Same day baking isn’t possible.
Requires the simplest of ingredients i.e. flour and water	Creating a sourdough starter is time consuming itself, especially when you have to start from scratch.
Can preserve your sourdough starter for months or years	Can achieve delicious open crumb bread.

Can You Convert a Yeasted Recipe to Sourdough Starter?

You can certainly convert a yeasted recipe to a sourdough recipe. While this isn’t always possible, there are ways to convert your favorite yeast breads, as long as you look out for some of the factors listed below:

• The amount of yeast required
• Amount of flour
• Amount of water
• Timing

Since sourdough starter is composed of equal parts flour and water, you may need to reduce the same amount of flour and water in your bread recipe. This is because your sourdough starter is mostly liquid based, which is why you’ll need to pay attention to the amount of liquid you use in your bread baking recipe.

So Yeast or Sourdough Starter?

A sourdough loaf may sound incredibly appetizing, however when there is little to no time on your hands, it may seem convenient to opt for a commercial yeast bread recipe in its stead.

Like me, you might love the sourness of sourdough, and you can add homemade yogurt to enhance this!

Sourdough vs Yeast – FAQs