Generation of bitter blocker Maillard-dietary phenolic compound reaction products

Bitterness is a well-known aversive taste that can negatively impact consumer’s acceptance. The aim of this study was to investigate the generation of bitter blocker compounds derived from the bitter dietary phenolic compound epigallocatechin gallate (EGCg) through the Maillard reaction. Reaction models were investigated using different reaction variables (temperature, time, moisture, nature of sugars and amino acids, and reactants molar ratio) to obtain different phenolic-Maillard reaction products. Isotope labelling experiments using carbon labelled sugars were performed to identify the reaction products and compare the different reaction models. The main resulting reaction products were further isolated and purified for sensory analysis and accurate identification purposes to discover bitter blockers. A total of fourteen isolated reaction products were identified by accurate mass spectrometry analysis (HRMS) and nuclear magnetic resonance (NMR). Those reaction products were evaluated by sensory analysis through 2-AFC test comparisons and bitterness intensity ratings to determine their bitterness modulation properties. Two reaction products were found to significantly decrease the bitterness perception of caffeine bitter samples. The optimised Maillard reaction conditions to produce those bitter blockers were further described to provide new knowledge and insight regarding the generation of bitter blocker compounds during food processing.