Structural and Sensory Characterization of Key Pungent and Tingling Compounds from Black Pepper (Piper nigrum L.)

Abstract

To gain a more comprehensive knowledge on whether, besides the well-known piperine, other compounds are responsible for the pungent and tingling oral impression imparted by black pepper, an ethanol extract prepared from black pepper (Piper nigrum L.) was screened for its key sensory-active nonvolatiles by application of taste dilution analysis (TDA). Purification of the compounds perceived with the highest sensory impact, followed by LC-MS and 1D/2D NMR experiments as well as synthesis, led to the structure determination of 25 key pungent and tingling phytochemicals, among which the eight amides 1-(octadeca-2E,4E,13Z-trienyl)piperidine, 1-(octadeca-2E,4E,13Z-trienyl)pyrrolidine, (2E,4E,13Z)-N-isobutyl-octadeca-2,4,13-trienamide, 1-(octadeca-2E,4E,12Z-trienoyl)-pyrrolidine, 1-(eicosa-2E,4E,15Z-trienyl)piperidine, 1-(eicosa-2E,4E,15Z-trienyl)pyrrolidine, (2E,4E,15Z)-N-isobutyl-eicosa-2,4,15-trienamide, and 1-(eicosa-2E,4E,14Z-trienoyl)-pyrrolidine were not yet reported in literature. Sensory studies by means of a modified half-tongue test revealed recognition thresholds ranging from 3.0 to 1150.2 nmol/cm² for pungency and from 520.6 to 2162.1 nmol/cm² for the tingling orosensation depending on their chemical structure.

Alkamides: a critical reconsideration of a multifunctional class of unsaturated fatty acid amides

“…In a taste dilution analysis Dawid et al (2012) tested the active alkamides of black pepper, P. nigrum, to what extent they contribute to the pungent impression of the well-known aromatic amide piperine. While eight aromatic piperine analogues exhibited a clear pungent sensory profile, twelve long-chain C 20 -and C 18 -2E,4E-dienoic acid derived alkamides, possessing an additional isolated Z-double bond, induced a pungent impression as well as a long-lasting tingling sensation.…”

“…Moreover, amides with an isobutyl (a) or pyrrolidine part (k) were less pungent and tingling than the corresponding derivatives with a piperidine part (b). For example, eicosa-2E,4E,14Z-(13b) and 2E,4E,15Z-trienoic acid piperidide (14b) showed lowest threshold concentrations for pungency when compared to the corresponding pyrrolidides (13k, 14k) and isobutylamides (13a, 14a) (Dawid et al 2012). …”

“…33a, 101a (Tackie et al 1975) P. hancei Maxim. 101a, 117a (Narui et al 1995) P. longum L. 1a, 11a, 13b b , 16a, 33a, 36ab, 37 b , 39b, 46a, 47ab, 50b, 51a, 53b, 84a, 101ab (Dhar and Atal 1967;Koul et al 1988;Sun et al 2007;Li et al 2013) P. nigrum L. 8b, 13abk, 14abk, 16a, 33a, 34a, 37abkp, 38abk, 41k, 51a, 62ak, 89b, 99ab, 100a, 101abk, 103b, 112a, pipercycliamide (Wei et al 2004;Siddiqui et al 2004;Ee et al 2010;Dawid et al 2012) P. novae-hollandiae Miq. 101a, 112a (Loder et al 1969) P. peepuloides Roxb.…”

“…As derivatives of the straight-chain fatty acid synthesis the acid parts differ biosynthetically from structurally similar but branched carbon chains from amides of the genera Capsicum of the Solanaceae (Curry et al 1999;Aza-González et al 2011;Kehie et al 2015) or Ipomoea and Merremia of the Convolvulaceae family (Tofern et al 1999). In Piperaceae the alkamides are only known from the genus Piper, where they are frequently accompanied by so-called piperamides, another class of amides, differing by an aromatic ring in the acid moiety (Parmar et al 1997;Do Nascimento et al 2012;Dawid et al 2012). From the various amides of the Rutaceae fatty acid derived alkamides were mostly found in the genus Zanthoxylum, but were also reported for Tetradium daniellii (Reisch et al 1985) and Pilocarpus trachylophus (Andrade-Neto et al 1996).…”

Functional Metabolomics – a Useful Tool to Characterize Stress-Induced Metabolome Alterations Opening New Avenues Towards Tailoring Food Crop Quality

“…Especially, the application of taste dilution analysis followed by dose/activity considerations led to the discovery of many bitter, sweet, umami, pungent, astringent, salty, or sour sensing molecules in several plants, such as carrots [79,80], cocoa [81], asparagus [82][83][84], pepper [85], red currents [86], tea [87], stevia [88] or spinach [89] in the past. Due to the nowadays well-accepted fact that not only a single flavor-impact molecule, but a combinatorial code of multiple odor-and taste-active key compounds, each in its specific concentration, reflect the chemosensory phenotype and trigger the typical flavor profile of food products.…”