From beer manufacturing waste, researchers managed to extract proteins that can enrich vegetarian diets
Published 05/03/2024
Director of NTU’s Food Science and Technology program, Professor William Chen, and Senior Researcher, Dr. Chai Kong Fei. | Photo: NTU Singapore
Producing around 15.4 billion liters of beer per year, Brazil is in third place on the list of the largest beer manufacturers in the world. All this production, which basically involves barley malt, hops, yeast and water, generates a large amount of waste. Researchers at Nanyang Technological University (NTU), the largest research university in Singapore, are seeking to transform such waste into a food supplement.
Brazilian academic research indicates that for every 100 kg of processed grains, 125 to 130 kg of wet bagasse are generated. Globally, according to NTU, around 36.4 million tonnes of used grain are produced annually, which are disposed of in landfills or incinerated, contributing to greenhouse gas emissions. Beer pomace or BSG (brewer’s spent grain) is the most significant by-product of the brewing industry, representing 85% of total waste.
“Although some efforts are being made to reuse BSG in applications such as animal feed, biofuel production or composting, a substantial portion still ends up in landfills, generating greenhouse gases such as methane and carbon dioxide,” says NTU in press release.
Research from NTU’s Food Science and Technology program has created a method that extracts more than 80% of the protein available in leftover grains from brewing. The result is a product capable of enriching vegetarian diets and even being applied for cosmetic purposes. Check out some advantages observed by researchers when using this bagasse:
- They are safe for human consumption and of high quality, which makes them suitable for direct use in supplements;
- They can also increase the protein content of plant foods;
- It can also help reduce carbon emissions by avoiding waste
- Proteins are rich in antioxidants, which could not only protect human skin from pollutants but also extend the shelf life of cosmetics such as body lotions and moisturizers;
In addition to increasing the potential nutritional value of a plant-based diet, researchers believe that using beer pomace “would help mitigate a potential protein deficiency due to a predicted 73% increase in meat consumption by the year 2050, after the rapid growth of the global population”, as predicted by FAO.
How protein was extracted from beer pomace
To extract the protein, the researchers sterilized the Rhizopus oligosporus, a food grade fungus commonly used to ferment soybeans to produce tempeh -, a soybean food popular in Southeast Asia. The three-day process helps break down the complex structure of BSG, making its protein content more easily extractable.
The fermented BSG is then dried, ground into a powder, sieved and centrifuged to separate the protein, which would float to the top of the rest of the mixture. Once extracted, the protein can be added to foods to increase their protein content or combined with lotions or creams to increase their moisturizing and antioxidant properties.
The findings were published in the scientific journal Innovative Food Science and Emerging Technologies.
