Food bioactive peptides: functionality beyond bitterness.

This article focuses on bitter bioactive peptides (BAPs), which are peptides that elicit a bitter taste due to hydrophobic amino acids and interact with bitter taste receptors (TAS2Rs) found in the oral cavity and throughout the gastrointestinal tract (GIT). These peptides are naturally present or formed during food processing, storage, and digestion from both animal (notably caseins in dairy) and plant sources (such as chickpea, lupin, and bitter melon), and they exhibit various bioactivities including antihypertensive, antidiabetic, antioxidant, and immunomodulatory effects. Despite their potential as functional food ingredients targeting TAS2Rs to modulate physiological processes like appetite and glucose homeostasis, their inherent bitterness poses sensory challenges; strategies such as encapsulation and Maillard reaction–induced glycation have been explored to mask bitterness and improve acceptability. Limited in vivo studies, including human trials with bitter melon peptides, suggest clinical benefits like improved glycemic control, highlighting the promise of bitter BAPs in personalized nutrition, though further research is needed to optimize their delivery, stability, and efficacy.