Abstract
The rapid growth of the microbrewery sector, driven by the increasing demand for craft beers, has highlighted the importance of managing brewing residues to ensure environmental and economic sustainability. This review explores the primary byproducts of beer productionbrewer's spent grain (BSG), brewer's spent yeast (BSY), and hot trubanalyzing their composition and potential for upcycling. By exploring the Brazilian microbrewery sector as a case study, this work highlights its growth and challenges, while drawing insights that resonate with the global interest in sustainable practices within the craft beer industry. Traditional applications, such as animal feed and fertilizer, are expanded with new approaches like biofuel production, biogas, biopolymer synthesis, prebiotics, and healthy food ingredient development. An emphasis on the applications of BSG in food formulations, such as bread, cookies, nutrition bars, beverages, meat analogs, yogurt, and others, highlights its nutritional value and functional properties for developing food products. By integrating sustainable practices and advanced processing technologies, brewing residues can be transformed into high-value products, reducing waste and fostering economic growth. This review concludes that adopting circular economy principles is essential for aligning microbrewery operations with global sustainability goals while unlocking the potential of brewing byproducts for diverse industrial applications.