Pungent flavors

Allicin is an organosulfur compound obtained from garlic and leeks. When fresh garlic is chopped or crushed, the enzyme alliinase converts alliin into allicin, which is responsible for the aroma of fresh garlic. Allicin is unstable and quickly changes into a series of other sulfur-containing compounds such as diallyl disulfide. Allicin is an antifeedant, i.e. the defense mechanism against attacks by pests on the garlic plant.

Piperine is an alkaloid extracted from the plant, Piper nigrum. Responsible for the pungency of black pepper, it is used in food flavorings as a spice, in fragrances, as an insecticide, and as an animal pest repellent.

chemical compound

Sinigrin or allyl glucosinolate is a glucosinolate that belongs to the family of glucosides found in some plants of the family Brassicaceae such as Brussels sprouts, broccoli, and the seeds of black mustard (Brassica nigra). Whenever sinigrin-containing plant tissue is crushed or otherwise damaged, the enzyme myrosinase degrades sinigrin to a mustard oil (allyl isothiocyanate), which is responsible for the pungent taste of mustard and horseradish. Seeds of white mustard, Sinapis alba, give a less pungent mustard because this species contains a different glucosinolate, sinalbin.

Gingerol ([6]-gingerol) is a phenolic phytochemical compound found in fresh ginger that activates heat receptors on the tongue. It is normally found as a pungent yellow oil in the ginger rhizome, but can also form a low-melting crystalline solid. This chemical compound is found in all members of the Zingiberaceae family and is high in concentrations in the grains of paradise as well as an African Ginger species.

'''syn-Propanethial S-oxide (or (Z)-propanethial S-oxide'), a member of a class of organosulfur compounds known as thiocarbonyl S''-oxides (formerly "sulfines"), is a volatile liquid that acts as a lachrymatory agent (triggers tearing and stinging on contact with the eyes).

Lenthionine is an organosulfur compound with the formula . The compound consists of a 1,4- ring (pentathiepane). Lenthionine is a major component of the organosulfur compounds found in shiitake mushrooms (Lentinula edodes). onions, and garlic, and it is partly responsible for their flavor. The mechanism of its formation is unclear, but it likely involves the enzyme C–S lyase.

Sinalbin is a glucosinolate found in the seeds of white mustard, Sinapis alba, and in many wild plant species. In contrast to mustard from black mustard (Brassica nigra) seeds which contain sinigrin, mustard from white mustard seeds has only a weakly pungent taste.

Gluconasturtiin or phenethyl glucosinolate is one of the most widely distributed glucosinolates in the cruciferous vegetables, mainly in the roots, and is probably one of the plant compounds responsible for the natural pest-inhibiting properties of growing crucifers, such as cabbage, mustard or rape, in rotation with other crops. This effect of gluconasturtiin is due to its degradation by the plant enzyme myrosinase into phenethyl isothiocyanate, which is toxic to many organisms.

Polygodial a is chemical compound found in dorrigo pepper, mountain pepper, horopito, canelo, paracress, water-pepper, and Dendrodoris limbata.

Paradol is the active flavor constituent of the seeds of Guinea pepper (Aframomum melegueta or grains of paradise). It is also found in ginger. Paradol has been found to have antioxidant and antitumor promoting effects in a mouse model.

Shogaols are pungent constituents of ginger similar in chemical structure to gingerol. The most common of the group is [6]-shogaol. Like zingerone, it is produced when ginger is dried or cooked. Moreover, shogaol (and gingerol) are converted to other constituents when heat is applied over time, which is why ginger loses its spiciness as it is cooked.