Substances with Pungent Taste

The hot, burning pungent taste of paprika (red pepper), pepper (black pepper) and ginger is caused by the nonvolatile compounds listed in Table 22.9. 

Black pepper contains 3-8% of piperine (XXV) as the most irr5)ortant pungent substance. Pepper is sensitive to light since the trans,trans-diene system of piperine isomerizes to the cis,trans-diene system of the almost tasteless isochavicin on exposure to light. 

The concentration of the capsaicinoids XXX, storage conditions, and varies between 0.01 and XXXI, and XXXII (Table 22.9) in the fruits 1.2%. These compounds are the most pungent 

The high antioxidative activity of the two compounds is probably based on the fact that they are o-diphenols (cf. 3.7.3.2.1). 

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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Amyl nitrite ( -mil NYE-trite) commonly occurs in two isomeric forms n-amyl nitrite and isoamyl nitrite (3-methy-lamyl nitrite or 3-methylpentyl nitrite). In common usage, the term amyl nitrite most commonly refers to the isoamyl form. Both isomers occur as yellowish liquids with a distinctive sweet odor and a pungent taste. They are unstable and break down when exposed to air, light, or water. Both isomers are probably best known as vasodilators, substances that cause blood vessels to relax and expand, allowing an increased flow of blood through the body. Because of its widespread use as a hazardous recreational drug, isoamyl nitrite has been banned, except for specified medical uses. 

Camphor (KAM-for) is also known as gum camphor 2-camphanone i,7,7-trimethylbicyclo[2.2.i]heptan-2-one and i,7,7-trimethylhicyclo[2-2-i]-2-heptanone, among others. It is a volatile white waxy substance with a strong, characteristic odor and a hitter, cooling taste. Its odor has been described as fragrant, aromatic, pungent, or penetrating, similar to that of mothballs. The compound is obtained from the camphor tree, Cinnamomum camphora, which is native to many parts of the world, including the Indonesian islands of Java and Sumatra, as well as China, Taiwan, Japan, and Brazil. 

Detection of Pungent Substances.—The presence of pungent substances (pepper, pimento, mustard, etc.) in vinegar is detected by neutralising 50 c.c. exactly, evaporating, and tasting the residue. To obtain more certain indications, the residue is extracted with ether, the ethereal solution evaporated and the residue then left tasted. 

The butter-like note of unripened cheese can still be detected in Camembert and Emmentaler, but the intensity is lower, because other aroma substances formed during ripening become evident. Thus, Camembert also has mushroom-like, sulfurous and flowery notes and Emmentaler, nutty, sweet and fruity notes. In comparison with unripened cheese, the taste profile is extended to include a glutamate note and in the case of Emmentaler, an additional and characteristic sour/pungent impression. 

The sorbic acid molecule, like unsaturated fatty acid molecules, possesses two double bonds. As explained in organic chemistry, these bonds can be oxidized by air to form molecules with aldehy-dic functions. This reaction explains the unpleasant tastes imparted to fatty substances by oxidation. Concentrated aqueous solutions of sorbate effectively become yellow and take on a pungent odor. This observation is proof of a certain chemical instability of sorbic acid. Yet diluted solutions are noted to be significantly more stable in wine, in particular, the same quantity initially added is found after three years of bottle-aging. Consequently, the chemical instability cannot be presented as an explanation of the organoleptical deviations attributed to sorbic acid. 

Definition Water soluble high m.w. glycosidal substances occurring naturally in plants forms colloidal sol ns. on shaking with water Properties Tan, very fine powd. pungent disagreeable odor bitter taste sol, in water... 

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