Tesco confirms ‘fermented wheat flour' preservative purpose

On 15 December 2025, Tesco advised the Real Bread Campaign that the 'fermented wheat flour' in the chain’s own brand products is used 'to inhibit mould and thereby extending the freshness and shelf-life for the consume[r]'

When asked to if the organic acids generated for this purpose included propionic acid, 'customer care' advisors simply repeated the same statement.  Eventually, the Campaign was told: 'Unfortunately this is the only response we have had from the team and they have not provided any further information for us to supply to you. '

This confirmation of preservative function is the latest development in the Real Bread Campaign’s sector-wide investigation into labelling transparency and marketing honesty, which began in August 2025. Tesco's response to the Campaign at that time had been: 'We won’t be able to disclose that kind of information as it is confidential. I'm sorry that I couldn't be of more assistance to you on this occasion.'

Aldi and Asda have also advised that the function of the 'fermented wheat flour' in their products is to delay mould and extend shelf life. This echoes a statement published by the Federation of Bakers, which represents a number of the UK's largest industrial dough fabricators. It is used as a 'label friendly' alternative to preservatives such as purified  / isolated propionic acid (E280)  and calcium propionate (E282).

You can find further details, including updates about the other 12 companies investigated, on the Campaign website.

That's also where you can find the Real Bread Map, list of current Real Bread Loaf Mark licensees, FREE recipes, 17 years' worth of articles and information, and how you can JOIN the Campaign in support of our chartable work.

Note

The Campaign is not saying whether 'fermented wheat flour' is 'good or 'bad', or challenging any attempts at reducing food waste.  

Nor are we saying that any lack of transparency about the identity and purpose of 'fermented wheat flour' is illegal - food labelling law does not consider such 'clean label solutions' to be preservatives or any other category of additive.