isolation structure determination synthesis and sensory activity of nphenylpropenoyllamino acids from cocoa theobroma cacao application of chromatographic separation and taste dilution analyses recently revealed besides procyanidins a series of nphenylpropenoyl amino acids as the key contributors to the astringent taste of nonfermented cocoa beans as well as roasted cocoa nibs because these amides have as yet not been reported as key taste compounds this paper presents the isolation structure determination and sensory activity of these amino acid amides besides the previously reported n34dihydroxyecinnamoyl3hydroxyltyrosine clovamide n4hydroxyecinnamoylltyrosine deoxyclovamide and n34dihydroxyecinnamoylltyrosine seven additional amides namely n34dihydroxyecinnamoyllaspartic acid n4hydroxyecinnamoyllaspartic acid n34dihydroxyecinnamoyllglutamic acid n4hydroxyecinnamoyllglutamic acid n4hydroxyecinnamoyl3hydroxyltyrosine n4hydroxy3methoxyecinnamoyllaspartic acid and necinnamoyllaspartic acid were identified for the first time in cocoa products by means of lcmsms 1d2dnmr uvvis cd spectroscopy and polarimetry as well as independent enantiopure synthesis using the recently developed halftongue test human recognition thresholds for the astringent and mouthdrying oral sensation were determined to be between 26 and 220 micromoll water depending on the amino acid moiety in addition exposure to light rapidly converted these econfigured nphenylpropenoyl amino acids into the corresponding zisomers thus indicating that analysis of these compounds in food and plant materials needs to be performed very carefully in the absence of light to prevent artifact formation