Suppression of sensory bitterness of beverages via nanoscale complex coacervation

Bitterness suppression plays a crucial role in enhancing the flavor profiles of food and beverages. In this study, we developed a novel bitterness suppression strategy via selectively sequestering bitter compounds in solutions based on spontaneously generated nanoscale coacervates of small-molecular polyions with opposite charge, e.g., phytic acid (PA) and chitosan oligosaccharides (COS). The PA/COS coacervates exhibit universal bitterness suppression to different bitter beverages, like coffee, green tea, limonin and corn peptides solutions. Temporal dominance of sensations (TDS) showed addition of small amounts of coacervates effectively suppressed the bitterness of dark roasted coffee (30 % reduction). Untargeted metabolomics indicated the coacervates reduced coffee bitterness mainly via sequestering bitter compounds detected at higher levels in coffee, e.g., caffeine (29 % reduction), and di-esterified quinic acids (73 % reduction). This finding suggests that coacervates could provide a potent tool for enhancing the flavor profiles of food and beverages through the selective sequestration of bitter compounds.