Microbial fibre from fermentation waste – summary
- Western diets deliver 12 to 24 grams fibre versus recommendations
- Fermentation growth creates biomass waste streams rich in untapped microbial fibre
- Different fibre structures enable targeted benefits including gut immune and health
- Research shows microbial fibres can match functionality needed for food applications
- Using microbial fibre can close fibre gaps and unlock fermentation revenues
Fermentation is booming across the industry. But what do manufacturers do with the leftover biomass? Emerging research suggests microbial fibre could enable food products with targeted health benefits – and turn waste into a profitable new revenue stream.
“If you pass small stools, you need big hospitals.” That quote from Dr Denis Burkitt – surgeon, dietary fibre pioneer and author of 1979’s Don’t forget fibre in your diet – sums up the long-established link between fibre and health. However, many Western diets are still worryingly low in fibre: average daily intake is just 12-14g in the US and 18-24g in Europe, far below the recommended 28-42g.
The fibremaxxing trend has turned the social media spotlight on this “fibre gap”. Like most social media trends, fibremaxxing will probably have a short shelf life. However, while the maxxing buzz will fade, fibre awareness is likely to stay.
Gut health, physical health, mental health
Fibre is essential to keep the digestive system working smoothly, helping reduce the risk of colorectal cancer and inflammatory bowel disease. It also brings benefits beyond gut health.
Beneficial bacteria within the gut digest fibre molecules and produce metabolites that trigger effects throughout the body. This can help boost the immune system, lower cholesterol and reduce obesity. It could also influence the gut-brain axis leading to beneficial changes in mood, emotions, sleep patterns, appetite, cognition, motor function and even brain health.
Not all fibres act the same
Within the food industry, there is growing appreciation that specific fibres can deliver targeted health benefits. Research from RMIT University in Australia suggests that a fibre’s specific health benefits are linked to factors such as molecular structure, water-holding capacity and fermentation rate.
Among the more studied examples are the beta-glucans. For instance, 1,3-1,4 beta-glucans found in oats and barley have been shown to modulate the gut microbiota and reduce blood glucose and cholesterol levels. Meanwhile, 1,3–1,6 beta‑glucans from yeasts and fungi are recognised for their ability to modulate the immune system and have also shown potential anti‑microbial and anti‑cancer effects.
But beta-glucans are just one class of fibre. Identifying other novel fibres could open the door to a host of new health-promoting foods. The question is where to find them.
Growth in fermentation
The answer could lie in fermentation. Recent years have seen an explosion in fermentation in food production. Yeasts, algae, bacteria and filamentous fungi are all being used to improve texture, taste and shelf life or as a source of protein, oils and other nutrients.
In addition to these target food components, microorganisms also contain fibre – in some cases, fibres that aren’t found in plants. Typically, this fibre is thrown away in waste biomass after the target food components are extracted. But could we exploit it in food products?
Turning fermentation waste into value
Doing so could help tackle the fibre gap through “high fibre” versions of familiar products, analogous to the now common high protein products. Finding novel fibres could also enable food products that offer targeted health benefits.
Both possibilities turn what is currently waste into a highly valuable and lucrative sidestream for companies involved in biomass fermentation.
Closing the fibre knowledge gap
Beyond certain beta glucans and exopolysaccharides, microbial fibres have not been extensively studied. So, while there is a growing understanding and ecosystem around fermentation as a source of biomass, the industry still lacks insight into what fibres might be produced by commercial fermentation processes and whether they have specific health benefits.
However, there are efforts within the industry to answer these questions. For example, the Edible Microorganisms Consortium* is analysing the potential role of microbial fibre in creating more sustainable and resilient food systems.
A public-private collaboration part-funded by the Dutch government, the consortium is taking a holistic approach to the use of microbial fibres including:
- Production
- Extraction and purification
- Composition and functionality
- Health benefits
- Food safety issues
- Consumer acceptance
Early findings show fibre’s potential
Research is ongoing but has already turned up interesting initial results. The consortium has identified yeasts, bacteria, fungi and microalgae that contain levels of fibre of suitable composition and basic technical functionality (such as water-holding capacity) to be interesting for food applications.
An initial survey of 300 consumers also found a large majority were open to eating foods containing microorganisms “to a certain extent”. This suggests that products based on microbial fibre could find a willing market, especially among the more health conscious.
The consortium is in the process of identifying specific health benefits of these promising candidates using in vitro models of the human digestive tract and immune system. This includes exploring how biomass fractionation – i.e. using whole cells, disrupted cells or extracted fractions at different levels of purity – affects a fibre’s health impact and usability in food products.
Unlocking new health products and revenue streams
By increasing the industry’s understanding and portfolio of edible microbial fibres, research such as this lays the foundation for new generations of targeted health products. Products that look and taste like familiar foods while boosting the immune system, reducing inflammation or enhancing emotional wellbeing.
For companies running fermentation at scale, it promises a compelling commercial opportunity: transforming waste biomass streams into high-value functional ingredients.
* This project receives financial support from the Top Sector Agri & Food. Within the Top Sector, the business community, knowledge institutions and government work together on innovations for safe and healthy food for 9 billion people in a resilient world. This consortium is scheduled to run from 2024 to 2027.
