Abstract
Brewers’ spent grain (BSG) is the most abundant by-product of brewing. Due to its microbiological instability and high perishability, fresh BSG is currently disposed of as low-cost cattle feed. However, BSG is an appealing source of nutrients to obtain products with high added value through microbial-based transformation. As such, BSG could become a potential source of income for the brewery itself. While recent studies have covered the relevance of BSG chemical composition in detail, this review aims to underline the importance of microorganisms from the stabilization/contamination of fresh BSG to its biotechnological exploitation. Indeed, the evaluation of BSG-associated microorganisms, which include yeast, fungi, and bacteria, can allow their safe use and the best methods for their exploitation. This bibliographical examination is particularly focused on the role of microorganisms in BSG exploitation to (1) produce enzymes and metabolites of industrial interest, (2) supplement human and animal diets, and (3) improve soil fertility. Emerging safety issues in the use of BSG as a food and feed additive is also considered, particularly considering the presence of mycotoxins.Key points• Microorganisms are used to enhance brewers’ spent grain nutritional value.• Knowledge of brewers’ spent grain microbiota allows the reduction of health risks.Graphical abstract
Highlights
The recycling and exploitation of brewing residues, such as brewery wastewater, surplus yeast, and brewers’ spent grain (BSG), are critical goals for reduction of energy consumption and residue disposal costs, and for reduction of the associated carbon foot-print (Zupančič et al 2017)
Its relatively low cost makes Brewers’ spent grain (BSG) an interesting raw material that has the potential to be used for the production of goods with high added value
Brewers’ spent grain is the main by-product of the brewing industry, and it is regularly available in large amounts at a low market price
Summary
The recycling and exploitation of brewing residues, such as brewery wastewater, surplus yeast, and brewers’ spent grain (BSG), are critical goals for reduction of energy consumption and residue disposal costs, and for reduction of the associated carbon foot-print (Zupančič et al 2017). BSG is the most abundant by-product from the brewing process (i.e., 85% of total by-products) (Fig. 1). The global production of BSG has reached 39 million tons per year on average (Birsan et al 2019). Around 70% of the BSG produced is used as animal feed, with 10% used to produce biogas and the remaining 20% disposed of as landfill. Its relatively low cost makes BSG an interesting raw material that has the potential to be used for the production of goods with high added value
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
