Wet and dry brewery spent grain utilization for livestock feeding and its’ limitation

The practices and constraints of wet and dry brewery spent grain utilization for livestock feed were summarized. The abundant agro-industrial byproducts, including milling residues and occasionally surplus or damaged grain, are utilized to formulate concentrate feed supplements. The expanding brewing industry in Ethiopia has extracted brewery spent grain during beer production. In accordance with environmentally conscious policies and cleaner technology initiatives, there is an increased emphasis on recycling and preserving bioresources, such as brewer's spent grain (BSG), to diversify waste production and mitigate environmental impact. The short lifespan of the wet brewery grain associated with its high moisture content is the critical problem of farmers in utilizing the by-product. On the other hand, cost of drying is one challenge which leads farmers to directly use wet brewery grain. However, BSG's nutritional profile comprises 26.3% dry matter, 23.4% crude protein, and 17.6% crude fiber. It is considered a valuable source of undegradable proteins and water-soluble vitamins. While BSG is abundantly available in Ethiopia throughout the year, several factors present challenges to its reliable and sustainable use as livestock feed. These include timing, location, composition, environmental impact, technological feasibility, and economic viability. This paper provides an overview of brewery spent grain production and utilization, highlighting its alternative applications as a raw material in livestock feed production, energy generation, and biotechnological processes. Consequently, there is a necessity to develop technology for preservation methods and its utilization as a livestock feed supplement or as an ingredient in supplements.