Optimisation of the Quorn fermentation process for the production and extraction of functional mycoprotein

This project proposes to assess the technical and commercial feasibility of producing and extracting functional mycoprotein from the Quorn fermentation process. This process is based on the conversion of starch into protein by the fungus Fusarium venenatum. The resulting mycoprotein is currently solely used for the production of Quorn's food products. However a current collaboration between Heriot-Watt University (HWU) and the company showed that mycoprotein extracted from the fermented broth on a laboratory scale displayed outstanding foaming, emulsifying and gelling properties, highlighting their potential use as commercial functional proteins.

There is a need to develop valuable and sustainable functional proteins for the food industry. Indeed animal-based sources of proteins such as whey or egg are responsible with high greenhouse gas emissions. Similarly, the costs and environmental impact of functional delivery systems for drugs and bioactive compounds often hinder their commercialisation. On the contrary, Quorn's industrial processes reported 90% lower emission rates of greenhouse gas emissions and benefits on land and water footprints in comparison with beef products. The idea behind this project is to assess the development of functional mycoprotein as sustainable protein replacements for the industry.

The funding received will allow first to design and assess a mycoprotein extraction process according to protein purity, yield, functionality, composition and associated costs. The results obtained will then be used to investigate the technical and economic feasibility of optimising the Quorn fermentation process for functional protein production on a large scale.

In a first stage, a range of protein separation and purification methods will be screened in Nicholas Willoughby's laboratory. In parallel the composition and functionality of the resulting extracts will be characterised in Stephen Euston's laboratory. Based on this screening a protein extraction strategy will be designed and further optimised, while its economic impact will be assessed by Quorn.
Based on these results, the company will assess the viability of optimising its fermentation process to specifically produce functional mycoprotein. An adapted fermentation process with first be designed and optimised on a laboratory scale, followed by a series of scaled-up pilot trials. In parallel the composition and functionality profile of the resulting proteins will be monitored, as well as associated costs.

A number of economic, environmental and societal benefits would arise from this project. This research could pave the way for the development of sustainable functional mycoproteins for the food industry. Based on preliminary work it is estimated that up to 13,500 tons of mycoprotein (at 80% protein purity) could be produced per year. Based on current prices, this production could open up a market worth £78M per annum. In addition the extraction of functional mycoprotein from Quorn's main co-product would further reduce the company's environmental impact while opening up an additional market of up to £14M per year.

This project will contribute to improve quality of life by offering manufacturers cost-effective functional protein alternatives, allowing them to offer cheaper products to the benefit of consumers. In addition, preliminary results indicate that functional mycoprotein could act as fat replacer due to unique foaming and emulsifying properties, so could contribute to the reduction of obesity. This collaborative project will allow Quorn to access specific multidisciplinary expertise developed at HWU in protein extraction and characterisation. The partnership with Quorn will help establish Heriot-Watt University as a major Scottish and UK centre for sustainable protein production, and should lead to many years of collaborative research outwith this project.

Proteins are used as functional ingredients in a wide range of manufactured foods. In addition to their nutritional properties, proteins are excellent emulsifying, foaming and gelling agents and contribute to the structure and stability of formulated foods through these properties. Animal proteins (egg, milk) are popular due to their superior functional properties over plant proteins (soy, wheat). However, the sustainability of animal protein production is continually under scrutiny and alternative non-animal sources of protein with adequate functionality are being sought to overcome this issue. Quorn is a mycoprotein based meat replacer that has been shown to have excellent sustainability credentials. Our previous work has demonstrated that a functional mycoprotein product can be prepared from the leftover fermentation broth after separation of the fungal biomass used for Quorn production. The waste broth contains extracellular proteins expressed by the fungi, as well as proteins from the cell membrane disrupted during mycelia separation. When concentrated and dried, the protein powder has excellent emulsifying and foaming properties over and above comparable animal protein products. The current project will progress this work in a number of areas. Firstly, we will assess a number of separation and purification methods for their technical and economic suitability for production of high purity mycoprotein powders. Secondly, these processes will be assessed for their suitability for scale-up production of protein. Finally, we will assess the feasibility of fractionating the mycoprotein in to different protein classes to assess whether further functional diversification of the protein can be achieved. In parallel to this, Quorn will work on the control of the fermentation process to ascertain whether it is possible to manipulate the composition of the left-over fermentation broth to produce higher proportions of functional exo-proteins.