Functional Benefits of Brewer's Spent Grain and the Challenge of Developing Food Ingredients for Human Health.

Recent developments have highlighted the importance of using by-products such as brewer's spent grain (BSG) as functional food ingredients. BSG is a source of polyphenols, antioxidants, dietary fiber, and protein, all of which are crucial for preventing metabolic syndrome and cardiovascular disease. This review focuses on bioactive compounds in BSG, such as ferulic and p-coumaric acids, which are distinguished for their antioxidant and anti-inflammatory properties. These compounds play a vital role in liver protection by boosting antioxidant enzyme activity and reducing inflammation and oxidative stress. Additionally, arabinoxylans (AX) in BSG enhance gut health by promoting the growth of beneficial microbiota. The review also identifies gaps in understanding how processing affects bioactive compound bioavailability in foods, emphasizing the need for innovative food technologies to enhance nutrient release and absorption, including the recent studies that show the role of gut microbiota in fermenting BSG components, leading to the release of beneficial compounds, such as ferulic and butyric, which positively influence health and metabolism. Despite these advancements, further research is essential to explore the interactions within the gut, liver effects, and the overall health benefits of BSG, aiming to optimize processing techniques to preserve its nutritional value and promote sustainable food innovation.