Discovery and Structure Determination of a Novel Maillard-Derived Sweetness Enhancer by Application of the Comparative Taste Dilution Analysis (cTDA)

Abstract

Application of a novel screening procedure, the comparative taste dilution analysis (cTDA), on the non-solvent-extractable reaction products formed in a thermally processed aqueous solution of glucose and l-alanine led to the discovery of the presence of a sweetness-enhancing Maillard reaction product. Isolation, followed by LC-MS and 1D- and 2D-NMR measurements, and synthesis led to its unequivocal identification as N-(1-carboxyethyl)-6-(hydroxymethyl)pyridinium-3-ol inner salt. This so-called alapyridaine, although being tasteless itself, is the first nonvolatile, sweetness-enhancing Maillard reaction product reported in the literature. Depending on the pH value, the detection thresholds of sweet sugars, amino acids, and aspartame, respectively, were found to be significantly decreased when alapyridaine was present; for example, the threshold of glucose decreased by a factor of 16 in an equimolar mixture of glucose and alapyridaine. Studies on the influence of the stereochemistry on taste-enhancing activity revealed that the (+)-(S)-alapyridaine is the physiologically active enantiomer, whereas the (-)-(R)-enantiomer did not affect sweetness perception at all. Thermal processing of aqueous solutions of alapyridaine at 80 degrees C demonstrated a high thermal and hydrolytic stability of that sweetness enhancer; for example, more than 90 or 80% of alapyridaine was recovered when heated for 5 h at pH 7.0, 5.0, or 3.0, respectively.

Application of acid whey and set milk to marinate beef with reference to quality parameters and product safety

“…0.5 c.u. Bitter taste related to presence of free amino acids, such as: valine, methionine, isoleucine, phenylalanine and arginine, as well as peptides (Ottinger et al, 2003) may be intensifi ed due to ongoing proteolysis processes (Okoń and Dolatowski, 2014). In studies on the infl uence of probiotic bacteria strains on the free amino acids profi le and sensory factors, Okoń and Dolatowski (2014) observed that the intensity of bitter taste did not correspond with the percentage share of bitter amino acids in the tested product.…”

Validity of early indirect models of taste active sites and advances in new taste technologies enabled by improved models

“…Examples of materials claimed to enhance sweet taste that we evaluated include soluble starch, [86] D-catechin, [87] alapyridaine, [88] and neohesperidin dihydrochalcone. [89] However, in formulations of these and other claimed enhancers with sucrose, fructose and glucose at intermediate levels of sweetness intensity (i.e.…”

Moleküle und biologische Mechanismen des Süß‐ und Umamigeschmacks

“…[76] Modellexperimente zeigten, dass dieses Pyridiniumsalz bei der Maillard-Reaktion von l-Alanin und Glucose als racemisches Gemisch gebildet wird (Schema 1). [77] Obwohl selbst geschmacklos, stellte sich heraus, dass das Enantiomer (+)-(S)-Alapyridain die menschliche Erkennungsschwelle für umami und süße Reize deutlich herabsetzt, während das (À)-(R)-Alapyridain physiologisch nicht aktiv ist. [78] Zusätzliche Studien zu Struktur-Aktivitäts-Beziehungen (SAR-Studien) zeigten, dass ein Austausch der Alanineinheit in 42 gegen einen Glycinrest das süß verstärkende Alapyridain in einen Bittergeschmack-Inhibitor überführt.…”