It’s clear that sourdough from a bakery tastes different from the sourdough loaves you’ll find on a supermarket shelf. That’s because they’re made from different processes – one uses long, slow fermentation while the other uses extra ingredients to speed the process up. Here’s what that means in practice.
The short answer: time and fermentation
Real sourdough is made using a live starter culture – a mixture of wild yeast and naturally occurring bacteria that ferments the dough over many hours, sometimes days. That long, slow fermentation is what gives genuine sourdough its characteristic tang, its open crumb, its chew, and its crust. It’s also what makes it digest differently from a quickly made loaf.
Industrial sourdough, the kind you’ll find in most supermarket aisles, is typically made using the Chorleywood Bread Process, a high-speed method developed in the 1960s that compresses hours of fermentation into minutes. To get any sourdough flavour at all, manufacturers add vinegar, citric acid, or ‘sourdough flavouring’. The result looks the part while the taste and the texture tell a different story.
What happens during real sourdough fermentation
When a baker feeds a sourdough starter with flour and water, two things happen. Wild yeast produces carbon dioxide, which makes the dough rise. Lactobacillus bacteria produce lactic and acetic acids, which give the bread its flavour, its keeping qualities, and its effect on the gut.
The balance between these two acids determines the character of the finished loaf. A longer, cooler fermentation produces more acetic acid – sharper, more pronounced sourness. A warmer, faster ferment produces more lactic acid – milder, more like yogurt in flavour. A skilled baker manages this balance deliberately, adjusting temperature, hydration, and timing to get the result they’re after.
That process cannot be rushed without losing something, and it cannot be replicated by adding an acid to a fast-made dough.
Why the texture is so different
Supermarket bread, including most supermarket sourdough, is made to be soft, uniform, and sliceable straight out of the bag. That softness comes partly from added fats, emulsifiers, and improvers, and partly from the Chorleywood Process itself, which overdevelops the gluten structure in a way that gives a fine, even crumb but none of the irregular holes you’d find in a properly fermented loaf.
Real sourdough has an open, irregular crumb – those uneven holes aren’t imperfections, they’re evidence of proper fermentation at work. Long fermentation partially breaks down the gluten structure, making the bread easier to digest for many people, including some who find modern wheat bread difficult to tolerate. It’s worth noting this is not the same as being gluten-free; sourdough made with wheat still contains gluten but the fermentation process does change how that gluten behaves.
What's in supermarket sourdough
The ingredients list is where the real difference becomes clearest. Real sourdough needs four things: flour, water, salt, and a live starter culture. That’s it.
A recent Real Bread Campaign investigation found that a number of supermarket and branded sourdough products contain ingredients including: wheat flour, water, yeast (baker’s yeast, added on top of any starter), salt, vinegar, citric acid, flour treatment agents, emulsifiers, and in some cases acidity regulators. Some listed ‘sourdough flavouring’ as a separate ingredient, which says everything you need to know about how much genuine sourdough flavour was created by the fermentation process.
Our bread: flour, water, yeast, and time
At All You Knead, we bake without additives or preservatives. Our sourdough is made the proper way – long fermentation, no shortcuts, nothing added that doesn’t need to be there.
We’re a family-run bakery based in Chorley, Lancashire, supplying our own cafés at Whittle-le-Woods and Haigh Woodland Park in Wigan, as well as a growing number of local independent businesses. Everything is baked fresh in our central bakery and travels a very short distance to where it’s sold. You can pick up our bread at both cafés, or pre-order online for collection from your preferred location.
Common questions about sourdough
Is sourdough better for you than regular bread?
The research is ongoing, but there is evidence that the long fermentation process in genuine sourdough partially breaks down phytic acid (which can inhibit mineral absorption), makes gluten easier to digest for some people, and produces a lower glycaemic response compared to standard bread.
Why does bakery sourdough cost more than supermarket sourdough?
Because it takes longer to make. A Chorleywood Process loaf can be made in a couple of hours. A properly fermented sourdough takes at minimum 12–24 hours, and often longer. That time is reflected in the price, along with the skill involved in managing a live culture and the fact that a small independent bakery doesn’t benefit from the same economies of scale as a factory producing millions of loaves a year.
How do I know if sourdough is the real thing?
Ask what’s in it, a genuine sourdough baker will give you a short ingredients list and be happy to discuss their starter. And if the bread has a two-week shelf life, there’s your answer.
https://www.allyouknead.co.uk/cafe-haigh-woodland-park/Find us at 60 Preston Road, Whittle-le-Woods, Chorley (Mon–Sat, 8am–3pm) and at the Kitchen Courtyard, Haigh Woodland Park, Wigan (open daily from 10am). You can also pre-order bread online via our website for collection from either location.