Chickens to benefit from bioethanol by-product research

According to new research, supported by the Engineering and Physical Sciences Research Council (EPSRC), the humble chicken could be the unexpected beneficiaries of the growing biofuels industry.

The research claims it has long been known the yeasty broth left over after bioethanol production is nutritious, but it has taken a collaboration between Nottingham Trent University and AB Agri, the agricultural division of Associated British Foods, to prove that yeast protein concentrate (YPC) can be separated from the fibrous cereal matter.

The researchers have also shown YPC may be a cost-competitive substitute for imported soya-based, and similar, high-value protein feed currently used in the diets of chickens bred for meat production.

Project supervisor Emily Burton, from the university, says this work is only just beginning: ‘Bioethanol is already a 60 billion litre per year global market but this project shows the fuel itself is only half the story – immense value lies within other co-product streams too. As well as the proteins, the yeast content provides important vitamins and other micronutrients.’

Produced by distilling and fermenting wheat and other agricultural feedstocks, bioethanol has particular potential for use as a petrol substitute. Currently, the dried distiller’s grains with solubles (DDGS) generated as a co-product are sold to the cattle-feed market but this is not big enough to absorb all material that would be generated if bioethanol production ramps up significantly in future.

Burton believes the project helps address an issue often raised in connection with cereal-based biofuels: ‘One concern with bioethanol is the perception it will compete with food crops for limited farmland. Our new work shows how the two can live side by side.’

The new, patented process separates DDGS into three fractions – fibre, a watery syrup and YPC, allowing global production of almost 3 million tonnes of supplementary protein per annum alongside current levels of bioethanol produced. A project at a US bioethanol facility is now up and running, demonstrating the performance of the process at factory scale.