Abstract The utilization of food processing by-products for the manufacturing of added-value products promotes circularity in food systems. The upcycling of agro-industrial side streams, generated in urban areas, fosters the sustainability of local food production and consumption, alleviating the waste management systems. Brewers’ Spent Grain (BSG) is the main by-product of the brewing industry. In this study, BSG was incorporated into a bread product to examine its potential as an effective ingredient for enhancing bread nutritional quality. Breads, consisting of flour, yeast, sugar, salt and BSG (flour substitution by 15 and 30% w/w) were formed, baked, packed in Polyethylene-Polypropylene bags, and stored at constant temperatures of 20, 30 and 40 °C, applying an accelerated shelf-life testing protocol. Quality loss during storage was systematically monitored through microbial growth, color and texture change, applying also sensory analysis. The shelf-life of bread products was calculated. Proximate analysis showed that bread samples enriched with 15 and 30% BSG presented significantly increased total dietary fiber (from 7.4% in control, non-BSG bread samples to 16.4 and 24.4%, respectively) and protein content (from 7.5 to 8.1% and 11.3%). The 15% BSG-enriched bread samples were characterized by improved nutritional value, as well as sensory characteristics (such as texture/firmness, taste), after production and throughout storage. Despite the higher nutritional values, the 30% BSG-enriched bread samples exhibited reduced sensory acceptability (denser/firmer and darker product with bitter taste), leading to shorter sensory shelf-life. The shelf-life of non (0%), 15% and 30% BSG-enriched bread samples at 20 °C was calculated as 14, 12, and 6 days, respectively. Graphical Abstract
Papadimitriou et al. (Thu,) studied this question.