The use of psyllium husk in gluten-free baking could be a thing of the past after University of Adelaide researchers discovered the seeds of two native species of Plantago produce mucilage that could be used as a natural additive.

The research, conducted by a team that was led by Dr James Cowley, discovered the difference in mucilage content and chemistry of each of the Plantago species affected its suitability for use as a food ingredient.

De Cowley said these differences led to wildly different impacts when added to gluten-free bread.

“Adding Plantago flour made the doughs more elastic, making them more resistant to collapsing during fermentation, which made breads with better appearance and texture,” he said.

“We believe this comes down to the differing chemistries of the mucilage, as the amount alone did not explain the effects. For example, two native species – P. cunninghamii and P. turrifera – produced similar or better quality breads to commercial P. ovata despite having a much lower mucilage content.”

Mucilage is a sticky gel of dietary fibre that is produced by many seeds when they are wetted.

Dr Cowley, who has studied Plantago seeds for more than a decade, said there was increasing desire among coeliacs and non-coeliac gluten-avoiders for better gluten-free bread products that have shorter ingredient lists.

“Consumers are increasingly looking for ‘clean label’ products that are perceived as ‘healthier’ or ‘more natural’,” he said.

“Hydroxypropylmethylcellulose, known as HPMC or E464, is one of the most common gluten replacements in bread but is often met negatively, as it is perceived as ‘artificial’ or ‘unnatural’.

“Psyllium husk, which is extracted from Plantago ovata for use in gluten-free doughs, can be included on ingredient labels as vegetable fibre without the need for an E number, allowing it to be more ‘clean label’.”

Dr Cowley said research published in Food Hydrocolloids had shown whole seed flours that use the inner seed parts as well as the mucilage-containing husk were preferable to those where the mucilage is removed.

“Commercial psyllium husk is made by removing the mucilage through a grinding process, but this produces a large amount of waste with no high-value commercial use, despite our group recently showing that the waste is high in nutrients,” he said.

“We hope that more products may use Plantago whole-seed flour, which still contains that beneficial mucilage, as a more sustainable alternative to purified psyllium husk.”

Dr Cowley said the results, which showed softer, more springy breads that had more volume was also promising for consumers who take texture into consideration.

“Consumers consider texture and appearance to be critical to their perception of a quality gluten-free bread, and they are looking for springy, airy loaves that behave as closely to gluten-containing breads as possible,” he said.

“We aren’t quite there yet, but new additives and formulations appear all the time. Hopefully one day we can produce clean-label gluten-free breads that are just as good as the real thing.”