Identification of bitter constituents in milk-based infant formula with hydrolysed milk protein through a sensory-guided technique

Abstract

Key bitter taste-active fractions were fractionated and identified from cows' milk-based infant formula (IF) containing hydrolysed (bovine) milk protein. A systematic and sensory-guided approach was applied to separate and identify taste-active bitter peptides. The degree of hydrolysis for the extensively hydrolysed (EH) and partially hydrolysed (PH) samples was >22% and <22%, respectively. The sample with EH milk protein had the highest sensory score for bitter taste, and more bitter peptides were identified from it. The proportions of micromolecular peptides (<500 Da) distributed in the EH sample and PH sample were approximately 100% and 80%, respectively. More importantly, a sequential difference in the peptides generated from milk-based IFs with PH and EH was observed, and total numbers of four and nine peptides were discovered in the PH and EH samples, respectively; Ser–Leu–Ala, Leu–Leu–Pro and Try–Try–Gln, were reported for the very first time.