Pungency relationships

Chemesthesis. The term chemesthesis has been introduced to classify thermal and painful sensations experienced in the mouth (26). Chemesthesis refers to a chemical sensibility (mouthfeel) in which certain chemicals direcdy activate nerve fibers at the level of the basal membrane in the mouth. The sensations are analogous to similar effects at the skin surface where there is a close anatomical and functional relationship. Sensations include the "hot" of capsaicin and piperine, which are active components of chili and pepper, the coolness of menthol and the irritation of chemicals such as salt at high concentrations [FIGURE 4]. Some of the descriptive terms used to make qualitative distinctions in food sensations include pungency, freshness, tingling, burning and sharpness. 

The widespread use of the terms pungent or bite component, capsaicin pungency or sensory pungency has tended to be confusing. To recognise the cause and effect relationship clearly, the stimulant should be identified only by its common or chemical... 

On another important taste, pungency, Dr. Govindarajan said in his paper that this sensation must be measured to accurately describe the flavor of certain foods. He has also suggested a relationship between taste and chemical structure as has already been done in the cases of other tastes. 

Various studies have evidenced strict structure-activity relationships within capsaicinoids, and the existence of these relationships provided a hint for the existence of a specific receptor [72]. On the other hand, different end-points have been used in the literature, and it is difficult to draw a consistent picture. In vivo assays such as pungency and ocular irritancy, functional assays such as the measurement of calcium currents in dorsal root ganglion neurons, and receptor assays such as the displacement of labeled RTX have been used. The relationship between the results of these assays is, at best, approximate [75]. 

Famini, G.R., Aguiar, D., Payne, M.A., Rodriguez, R. and Wilson, L.Y. (2002) Using the theoretical linear energy solvation energy relationship to correlate and predict nasal pungency thresholds. J. Mol. Graph. Model., 20, 277-280. 

Newman, A. A., 1954a, Natural and synthetic pepper-flavoured substances. 5. Pungency and structure relationships. Chem. Prod. (London) 17 14-18. 

Pharmacological studies on gastrointestinal tract, cardiovascular and respiratory systems, thermoregulation, as well as nociception and anaesthesia were summarized by Suzuki and Iwai (1984). Relationship between pungency and chemical structure of capsaicin and its natural as well as synthetic analogues was also a topic... 

Investigations of the structure/effect relationship show that the intensity of the pungency does not change when 8-methyl- ran5-6-nonenoic acid in capsaicin is replaced by nonanoic acid (9 0). However, it decreases when shorter, e.g., 8 0 (75%), 7 0 (25%), 6 0 (5%), or longer fatty acids, e.g., 10 0 (50%), 11 0 (25%), are introduced. 

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