Incorporation of Microencapsulated Bioactive Peptides from Brewer's Spent Grain into Wheat Crackers: Effects on Technological and Bio-functional Properties.

The valorization of agro-industrial by-products as sources of bioactive compounds represents a key challenge for sustainable food systems. Previous studies demonstrated that microcapsules containing bioactive peptides derived from brewer's spent grain (BSG) exhibited antioxidant, antihypertensive, antidiabetogenic, and hypoglycemic effects in animal models. However, their application in real food systems remains unexplored. In this study, wheat crackers enriched with microencapsulated bioactive peptides from BSG were developed to evaluate their technological characteristics and post-digestive bio-functional properties. Two formulations were prepared: control crackers (C) and crackers containing 2% microcapsules (CM). The incorporation of microcapsules reduced the spread ratio (13.2 vs. 9.8) and increased hardness (1660 vs. 2518 g), while promoting darker and redder color. FTIR analysis suggested the presence of peptide-polysaccharide interactions in the enriched crackers associated with the encapsulating matrix. After simulated gastrointestinal digestion, amino acid profiling of dialysates revealed differences in the bioaccessibility patterns between C and CM. Additionally, CM showed higher inhibitory activity against α-glucosidase (90 vs. 85%), DPP-IV (73 vs. 61%), tyrosinase (54 vs. 40%), and ACE-I (40 vs. 37%) than C, with similar antioxidant activity. These results demonstrate that microencapsulation enables the incorporation of BSG-derived peptides into a cereal-based matrix while preserving their bioactivity, highlighting their potential application in the development of functional foods targeting metabolic health.