Structural and Functional Characterization of a Multimodal Taste Enhancer in Beef Bouillon

摘要

Aimed at investigating taste enhancers in beef bouillon, taste activity-guided fractionation combined with the comparative taste dilution analysis led to the discovery of the presence of a sweet enhancing compound. Model Maillard reactions, spectroscopic and synthetic experiments revealed the previously unknown l-(l-carboxyethyl)-5-hydroxy-2-(hydroxylmethyl)-pyridinium inner salt, named alapyridaine, as the first nonvolatile, tasteless sweet enhancer reported. Sensory analysis of synthetic beef taste reconstitutes spiked with synthetic alapyridaine in its "natural" concentration revealed a significant increase in sweetness, but also in the salty and umami character. Additional systematic sensory studies demonstrated for the first time that this compound is a general taste enhancer which is able to simultaneously intensify sweet, salty and umami taste modalities. Studies on the influence of the stereochemistry on sensory activity revealed the (+)-(S)-alapyridaine as the physiologically active compound, whereas the (-)-(R)-enantiomer did not show any effect.