A team of students at Te Whare Wānanga o Waitaha, the University of Canterbury, has begun laboratory testing to determine whether spent grain from breweries can be converted into nanocellulose, a high-performance material used in products ranging from electronic circuit boards to cosmetics.
The project, known as Nanobrew, focuses on one of the brewing industry's largest waste streams. Approximately 85% of brewing waste consists of spent grain, which spoils rapidly and must typically be collected the same day it is produced to remain suitable for animal feed.
Because spent grain is difficult to compost, breweries often sell it as livestock feed or send it to landfills, where it contributes to greenhouse gas emissions. The research aims to create a higher-value use for the byproduct by extracting nanocellulose from the grain.
Nanocellulose is a lightweight, high-strength material with applications in wound dressings, oil remediation, cosmetics, biodegradable materials and other advanced products. Researchers at the University of Canterbury's School of Product Design are already investigating several of these uses.
The student team includes 10 biochemistry, biology and engineering students working with a local brewery, brewing industry organizations and breweries across New Zealand to evaluate the concept over the coming months.
The process under development uses two specialized enzymes to break down the plant structures surrounding cellulose fibers in barley grain before converting the fibers into nanoscale particles.
One of the enzymes is an ancestral endoglucanase reconstructed through computer analysis of proteins from multiple species. Researchers selected the enzyme because previous research has shown it to be more thermally stable and resistant to varying conditions than naturally occurring versions.
The project's long-term goal is to design a bioreactor in which bacteria produce the enzymes needed to process spent grain into nanocellulose.
The research is part of the international Genetically Engineered Machine synthetic biology competition, where the team's results will be evaluated during the organization's annual jamboree in Paris in November.
The project also marks the second time the University of Canterbury has incorporated the competition into an undergraduate course, allowing students to develop and complete a research project from concept through presentation.
The team expects preliminary results within the next few months and plans to complete the research by October before the international competition. The students also intend to share their findings with local brewery partners and the broader community after returning from Paris in December.
Source: University of Canterbury, "UC students eye billion-dollar use for beer waste"