Revolutionizing Dairy Processing: Scalable Filtration and Bio-guided Strategies for Isolating Bioactive Compounds from Colostrum Streams

Colostrum, which is rich in bioactive peptides and oligosaccharides, is typically produced in excess of the calf’s requirements, presenting an opportunity for additional utilization. While most commercial processes aim to preserve whole colostrum or isolate its immunoglobulins by membrane filtration, minimal emphasis has been given to optimizing processes to isolate and better understand the properties of colostrum peptides and oligosaccharides. In this work, we isolated, concentrated, fractionated, characterized, and evaluated the in vitro biological properties of colostrum-derived bioactive peptides and oligosaccharides. Optimizing feed flow and transmembrane pressure during the ultrafiltration of colostrum whey with a hollow fiber membrane improved permeate flux by ~60%, without compromising the selective retention of protein (96-98%) and permeation of oligosaccharides and peptides ( >96% after 3 diafiltrations). Whey permeate underwent two filtration strategies to A) concentrate oligosaccharides and peptides to produce rich pools by two spiral-wound nanofiltration membranes or B) fractionate the oligosaccharides from the peptides to generate oligosaccharide-enriched and peptide-enriched fractions using a 600-800 Da tight ultrafiltration membrane. During whey permeate concentration by nanofiltration, optimization of feed flow and transmembrane pressure doubled permeate flux for each membrane while one membrane achieved eight-fold faster permeate flux compared to the other. The recovered pools exhibited high oligosaccharide and peptide retention (99-100%) and prebiotic, antidiabetic, antihypertensive, and antioxidant activities. Fractionation of whey permeate resulted in an oligosaccharide-enriched fraction exhibiting equivalent or higher selective prebiotic growth and α-glucosidase inhibitory activity compared to the fraction enriched with small peptides, which correlated to oligosaccharide content by quantification and glycomic profiling. Conversely, the peptide-enriched fraction exhibited higher angiotensin-converting enzyme inhibitory and antioxidant activities, supported by peptide profiling. These results highlight the simultaneous impact of critical filtration conditions on the recovery of oligosaccharides and peptides and their potential applications for enhancing human health as an alternative avenue to revalorize dairy streams.