The Differences Between Sourdough Bread and Soda Bread

Difference between sourdough bread and soda bread

People often ask if sourdough bread and soda bread are the same thing. The quick answer is no.

While both sourdough and soda bread share some similarities, such as the lactic acid inside the bread, they both use different ingredients and processes – which also means they taste different, too.

However, as a baker and a self-proclaimed sourdough enthusiast, I feel that it is my duty to explain the difference between the two breads to clear things up for anyone who finds themselves asking this question. From the main ingredients to their taste and even their origins, I’ve compiled everything you need to know about the differences between sourdough and soda bread, so you can spend less time Googling for answers and more time baking.

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What is sourdough bread?

What is sourdough bread?

Sourdough bread is slow-fermented bread that requires no commercial yeast in order to rise. Instead, it uses a sourdough ‘starter’, which is a mixture of fermented flour and water that contains wild yeast and good bacteria to make the bread rise. This also gives sourdough the signature tangy flavour and slightly chewy texture that people have enjoyed for centuries.

Although sourdough is made from a live fermented culture, known as a sourdough starter, the three main ingredients in sourdough are flour, water and salt. In fact, you can make your own sourdough starter by simply combining flour and water together in a jar and allowing the fermentation process to do its thing.

Meanwhile, the wild yeast you find in sourdough has more flavour than commercial yeast, and is natural in the sense that it doesn’t contain any additives – which is why it is often said to be healthier than your run-of-the-mill supermarket bread.

What is soda bread?

Soda bread is a type of quick bread which takes its name from the baking soda (or, sodium bicarbonate) that is used as a leavening agent instead of the traditional yeast.

Traditionally, soda bread is made using flour, baking soda, salt, and buttermilk. The buttermilk in the dough contains lactic acid, which reacts with the baking soda to form tiny bubbles of carbon dioxide – much like how the lactic acid reacts in sourdough. Other ingredients that are often added to soda bread include butter, egg, raisins, or nuts. 

An advantage of quick breads, like soda bread, is their ability to be prepared quickly and reliably, without requiring the time-consuming skilled labour and temperature control needed for traditional yeast breads.

How does soda bread taste?

How does soda bread taste

Soda bread typically tastes mild in flavour and has been likened to that of a biscuit. However, the taste of your soda bread does depend on what you put in it, as often people will add raisins, seeds, rye flour and even Guinness stout. 

Like most bread, soda bread isn’t designed to be eaten on its own – as this would be a pretty boring experience and not to mention dry. It’s meant to be served with butter, jam or meat.

Sourdough vs soda bread: what’s the difference?

Leavening agents

The main difference between sourdough bread and soda bread is in its leavening agent – sourdough bread rises due to the gasses released from yeast and bacteria fermentation, while soda bread rises from the gasses produced during the chemical interaction between baking soda and acids in the dough.

Since sourdough uses a ‘starter’ and soda bread uses baking soda, the two types of bread require different ingredients and baking processes, which means they have very different flavours and textures. On one hand, sourdough is slightly tangy with a chewy texture, while soda bread is mild, with a biscuit-like texture.

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Fermenting sourdough bread

The yeast in sourdough works on the bread dough at a very slow rate, as it uses the process of fermentation by consuming the starches and sugars in the flour. The fermentation process releases carbon dioxide gases and alcohol while also developing its gluten structure. 

Meanwhile, the soda bread reaction with lactic acid is instantaneous. The buttermilk reacts with the baking soda and gives off carbon dioxide gases as soon they have contact with each other. The process is a quick chemical reaction and does not use fermentation to turn it into bread. 

Soda bread uses softer wheat than sourdough 

Soda bread and other quick breads typically use softer wheat varieties like pastry flour, or all purpose flour, as the gluten in the flour is less important for the rise of the bread.

Sourdough on the other hand, will tend to be made with flour from harder wheat varieties, such as strong white flour. This is because the gluten in hard wheat is of a higher content, and gluten development is important in sourdough bread for the rise and structure of the bread.

Soda bread is quicker to make than sourdough

The main advantage of traditional soda bread is that it is quick to make. Once the dough is mixed, all you need to do is shape and bake the dough before you can enjoy it.

However, sourdough bread takes the same level of effort as soda bread to make, but takes a lot more planning and waiting to make sourdough bread due to the waiting time for fermentation to take place.

What are the similarities between sourdough and soda bread?

The dough in both soda and sourdough bread contain lactic acid. Sourdough uses the naturally occurring yeast from the sourdough starter which has lactic acid in it, while soda bread uses buttermilk. The reactions from both breads produce carbon dioxide bubbles which help the bread rise.

Fast facts about soda bread

1. Soda bread was first created by Native Americans

While soda bread is most famously attributed to Ireland, it was actually first created by Native Americans centuries ago. They were the first known people to be documented using pearl ash (a natural form of soda formed from the ashes of wood) to leaven their bread without yeast. 

2. 19th Century people believed cutting a cross on the top kept the devil out 

In the 19th century, it was widely believed that slashing a cross atop your bread let the devil out while the bread baked. It was also believed that the symbolism could be interpreted as blessing the bread and giving thanks. However, there is actually a practical reason behind the cruciform shape: these openings in the dough allow the bread to rise without splitting. 

3. The shape soda bread differs across different Irish regions

In Northern Ireland, people prefer the style of “farl”, while in Southern Ireland, they prefer “cake.” Farl, which translates to “four-part”, is normally rolled out into a circle, cut into four pieces, and baked in a frying pan rather than in an oven. Cake, on the other hand, is the version most often replicated in America. It’s the word used to describe soda bread that has been kneaded into a flat, round shape and baked in the oven.

Now you understand the difference between sourdough and soda bread, you can start baking your own. If you’re new to baking, this complete sourdough starter kit includes everything you need to bake your first loaf, or you stock up on your baking supplies by exploring our online range. 

If you need some more sourdough content in your life, be sure to follow us on Facebook and TikTok and be sure check out @youkneadsourdough on Instagram and hashtag #youkneadsourdough so we can see your sourdough creations. 

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