Single-cell protein made from fermented straw offers great advantages as a new animal feed, according to a review by Chinese scientists — but production techniques still need to be optimised to make this a realistic option for farmers.
Fermentation of readily available straw biomass using bacteria, yeasts and fungi to create protein is a “highly effective method,” the researchers wrote in the journal GCB Bioenergy. The process also creates a ‘win-win’ situation, whereby farm byproducts are managed and a sustainable feed produced as an alternative to soybean meal.
The approach compares favourably to traditional protein sources in terms of speed of production, efficiency and land use, they noted. However, as things stand, there are some limitations standing in the way of the concept becoming mainstream, including production costs and difficulties in scaling up the technique.
“There is an urgent need for the development of equipment and technologies specifically designed for straw-based single-cell protein production. This includes improving the pretreatment and storage processes of raw materials to optimize the production efficiency,” they wrote.
Tapping tech to perfect fermentation
Another area for possible improvement is synthesising optimised microbial strains for the fermentation process. Here, machine learning approaches could be effectively employed to screen for high-performing, robust strains, they noted, while the use of sensors and artificial intelligence could also help improve the precision of production more broadly.
While there is lots of reason for optimism, continued advancement and, ultimately, uptake will depend on factors beyond the scientists working in this area.
“The success and widespread adoption of microbial straw protein in the market will depend on favourable legislation, public acceptance, and competitive costs,” they said. “Given the current environmental impact of agricultural production, there is promising potential to explore the use of agricultural straw for microbial fermentation as a substitute for protein feed.”
With further developments in fermentation processes, other biomass sources such as food waste could be considered as sources of single-cell protein, they added.
