Sue's Blog

Caution: “cultured dextrose”

Chances are, you’ve never heard of cultured dextrose. Or if you’ve noticed it in your bread, you think it sounds vaguely like yoghurt and therefore safe.  Particularly if your bread is organic or says “no artificial preservatives”.


Listen up, people. If you are going to eat highly processed foods (and that includes bread), you need to understand what’s in it. Cultured dextrose is a particularly nasty additive that can cause all kinds of problems. See just a few consumer reports from our database:

I was very surprised at my own reaction to the bread preservative challenge. After two days, I got so incredibly tired, I thought I was getting sick. All I wanted to do was sleep; I felt like a slug … When I stopped the bread I felt better overnight – from story 1165

Moody, stressed out, anxious, itchy rash
I have always eaten a lot of bread. I would often eat 6 English muffins a day. I used to get very moody, stressed out and anxious …. I used to get very angry quickly and then in a split second I would feel like crying my eyes out. I also had an ongoing rash on my body, a feeling of ants crawling over my skin … I decided to stop eating preserved bread. Within a day I was feeling better – from story 207

Two years of underachieving due to the bread preservative
The introduction of preservative 282 in purchased bread coincided with a decline in our daughter's abilities. Her bread intake increased until she was eating about 8 or more slices/day and her performance decreased until we were able to get very little work out of her as she was unable to concentrate for more than about one minute at a time … we returned to using our bread maker after not having used it for nearly two years. After about ten days, we had a different child. She started concentrating! – from story 329

Urinary incontinence and asthma in seniors
We (aged 60 and 56) gave up 282 preservatives in bread after reading your book 'Fed up' about two years ago – within a week my wife (aged 56) was free of urinary incontinence and over a period of about three months I was able to give up all asthma medications -from story 338

Migraine trigger
As a migraine sufferer, I have found that 282 is one of my main triggers for a migraine attack. I have them very infrequently but very severely. By keeping a food diary I have been virtually able to avoid them - from story 204

How did this additive get into our food?

Surveys worldwide show that 80% of consumers are making a real effort to avoid food additives. This alarms the food industry because additives mean profits. So they are fighting back with what they call the Clean Label strategy. Get it? – clean labels, not clean food.

Clean Label foods remove numbers and chemical-sounding names, and replace them with the same chemicals listed as innocent-sounding ingredients.

Until recently, cultured dextrose used to be called preservative 280 (propionic acid), one of a group of chemicals that are used as mould inhibitors in bread, especially as preservative 282 (calcium propionate). Of the hundreds of additives permitted in our food, these four have been identified as some of the 50 additives most likely to cause consumer reactions.

Propionate preservatives were added quite suddenly to most Australian breads in the 1990s. Most consumers had no idea they were there – just a little number added to the list.

At that time, I was already reading labels because I knew my daughter was affected by some additives. No one reacts to one slice of preserved bread. Instead, the effects build up slowly, so it took me a while to realise that the effects of this new bread preservative were more devastating than any additive we had encountered so far – her symptoms were tiredness, forgetfulness, inability to concentrate.  Her father was affected with the same fatigue.  Reactions were related to how much they ate. First rule of toxicology: it’s the dose that makes the poison.

Our food regulators FSANZ refused to listen to my complaints (“We only want to hear from scientists, not consumers”) so with the help of some local paediatricians I undertook a study that was published in a medical journal in 2003 (1).

After that I appeared on national TV and heard from thousands of Australians – adults and children - who had stopped eating preserved bread and noticed an improvement. Their complaints ranged from  stomach aches, irritability, restlessness, learning disabilities or insomnia to migraines, headaches, urinary urgency, bedwetting, itchy rashes, chronic fatigue, asthma and even heart palpitations and seizures. Some of these symptoms are reported in people who are born with a condition called propionic academia in which natural propionic acid in the body cannot be metabolised and builds up to cause problems.  Studies in mice have also shown learning difficulties and autistic-type symptoms, such as withdrawal and lack of social contact.

Citing “consumer concerns”, some of the big manufacturers took 282 out of their bread. That was 12 years ago. Now, preservative 282 is used extensively in commercial loaves, rolls, crumpets, muffins, healthy grain breads, gluten free breads and especially in wraps.

But it is less likely to be called 282. These days, the food industry makes the same chemical by culturing propionibacteria in a medium such as dextrose, whey, rice or wheat. Due to “natural” manufacturing, they can claim “no artificial preservatives” (2).  This is how cultured dextrose has come to be accepted even in organic breads.

People commonly assume this additive is helpful because it prevents staling. Well, no, it doesn’t. The extra freshness of commercial bread is due to special fats.  Preservative 282 is only there to stop mould. There is no mould on a freshly baked loaf of bread, so if work benches and slicer blades are kept clean by wiping down with vinegar, there is no need for a mould inhibitor. “We don’t have time for that”, the manager of Darwin Bakery told me in the 90s, “we just fog”.  Putting hot loaves into plastic bags compounds the problem.  Hot bread shops and artisanal bakeries that keep clean and use paper bags are less likely to need this additive.

Propionates are one of the most difficult additives to avoid because they are widely used in a healthy food eaten every day. In one generation, many Australians have gone from eating none of this preservative to eating it every day of their lives.

How many ways is it being hidden?

We have identified that propionates can be shown as an ingredient called cultured OR fermented wheat, flour, rice, whey or dextrose. That means there are 10 ways to hide propionates so far. Even "whey powder" was believed to be a cultured form to judge by a child's reactions, so that makes 11 ways and counting.

What you can do:

Read the ingredients label on your bread. Avoid any of these numbers or names: 280-283, propionic, propionate and “cultured” or "fermented" ANYTHING. There are preservative free alternatives available such as Bakers Delight and Brumbys hot bread shops, Mountain Bread wraps, some instore bakery lines and some local bakeries. Or you can buy a breadmaker and fill your house with the magic smell of baking bread.

If you are a food manufacturer, there is a perfectly safe alternative: ethanol

UPDATE August 2022:

Fermented wheat flour is the bread preservative


Major supermarkets are changing what they sell. Always read the label!

Helga, Abbotts, Wonder and Lawson breads ALWAYS contain the hidden bread preservative as "fermented wheat flour" or "cultured wheat flour" (except for some of their gluten-free products).

But if a Coles supermarket does NOT have an instore bakery, then their bread will contain hidden bread preservative. If it does have an instore bakery, then Coles plain breads remain free of preservatives.

Woolworths may also be changing. Please tell us if you see hidden additives in their plain breads!




1.    Dengate S, Ruben A. Controlled trial of cumulative behavioural effects of a common bread preservative. J Paediatr Child Health. 2002;38(4):373-6.
2.    Glatz B. The classical propionibacteria: their past, present and future as industrial organisms. American Society for Microbiology News. 1992:58,(4):199-200.

More information

Factsheet on 280-283 propionates - the bread preservative

Harm from bread preservative confirmed (2021)

How propionates are hidden as ingredients by the food industry

Blog - Bread preservative linked to obesity and diabetes

 updated August 2022