Sourdough or sourfaux? How to spot ‘fake’ supermarket bread

Here's how to tell if you’re getting a genuine, gut-friendly loaf – or a sour-foe
Here's how to tell if you’re getting a genuine, gut-friendly loaf – or a sour-foe

It’s the worst nightmare of the sourdough-munching middle classes: that the rye sourdough loaf you brought home from the supermarket might, in fact, be “sourfaux.” Quelle horreur. And yet it’s more common than you might think.

The Real Bread Campaign has just celebrated a victory against Lidl, which has changed the name of its Sourdough Rye Crusty Bloomer to Crusty Wheat & Rye Bloomer, after a complaint was raised that it was not, in fact, genuine sourdough.

The complaint came from a disgruntled shopper who discovered that the loaf of bread was in fact made from majority wheat flour (56 per cent), with added baker’s yeast.

“This is basically a wheat loaf,” says Chris Young, coordinator for the Real Bread Campaign. The campaign group raised the complaint with trading standards, after Lidl originally rejected the customer’s grievance. “There’s possibly 12 per cent rye flour in it, which is still a miniscule amount for something that’s being sold to you as ‘rye’.”

It is the latest tussle in a series of disagreements between bakers and consumers about what can and can’t be called sourdough, which is by now verging on a national obsession. A genuine sourdough loaf in an independent bakery can cost £5 or more, while supermarket alternatives are half the price.

But how can you tell whether you’re getting a genuine, gut-friendly loaf or a sour-foe?

Sourdough, the oldest form of leavened bread, does not use added yeast and is made from a live “starter”, which is made from a paste of water and flour and left to ferment and grow yeast and bacteria. It typically contains just three ingredients: flour, water and salt.

Anything else on the ingredients list should ring warning bells. I tell Young I was pleased with myself when I bought an Aldi Specially Selected bake-at-home baguette “with sourdough”, but the ingredients list reveals it contains added yeast, an antioxidant and ethyl alcohol – so it’s actually closer to supermarket sliced white than a real sourdough loaf.

There are a few key things to look out for on the label, Young explains. “Genuine sourdough bread doesn’t involve the use of baker’s yeast or baking powder or anything else to make it rise,” says Young. “You take the flour, mix it with water and nurture those bacteria and yeasts until there are enough of them to make a starter, and the starter culture has enough yeast in it to make the dough rise.” So, any product that lists yeast is out.

Woman holding freshly baked sourdough bread
Genuine sourdough bread is made without any additives - alvarez

There’s a reason supermarkets skip this long and laborious process: it’s far quicker and cheaper to make bread through the industrial Chorleywood process, which uses additives, fats and high-speed mixing to cut the time it takes to make each loaf.

Which brings us to the second key signifier of a suspect bread: anything additive-laden is “sourfaux”.

“Genuine sourdough bread is made without any additives,” explains Young. It takes between 12 to 48 hours from making the dough to baking the bread. When shopping, look out for ascorbic acid, which puts a loaf “outside of our definition of real bread, full stop”. The same goes for any unrecognisable “funky stuff”: chemical raising agents, preservatives or emulsifiers. “Those emulsifiers aren’t necessary… and then there are [health] concerns that hang over ultra-processed foods more generally,” says Young.

Some processing aids such as phospholipase A2, which increases volume, or l-cysteine, a preservative, may have been used by a manufacturer, but they do not legally have to appear on an ingredients label so they are difficult for customers to avoid, Young adds. But he notes that we can look out for The Real Bread Loaf Mark on the label: bakers participating in the scheme must sign an agreement that they won’t use processing aids.

Those telltale holes in the sourdough crumb don’t necessarily guarantee a genuine loaf, either, as the same effect can be achieved from adding extra yeast.

The best, low-cost solution? Make your own. “This is what I do every weekend,” says Young. “You can make yourself two large loaves and a pizza from £1.10 of flour.” More time-consuming, granted, than grabbing a loaf from the supermarket shelf, but for an easier sleep in the knowledge that your sourdough is far from faux, it’s your best bet.