Several components and chemicals contribute to the physical perception of taste. The coolness or spiciness of a food can be detected in vinegars, mint chewing gum, cinnamon toothpaste, and jalapeño peppers. The tongue can also “feel” other sensations that enhance the basic tastes. These are largely detected by the somatosensory system.
Substances with pungency (spiciness or heat) cause a burning sensation by activating nerves and receptors in the skin of the mouth. This particular sensation, called chemesthesis, results from the stimulation of somatosensory (pain/temperature) fibers and whose interpretations are carried to the brain by a different set of nerve fibers than those of taste buds. Other parts of the body with exposed membranes, but no taste receptors (such as the nasal cavity, under the fingernails, surface of the eye or a wound), produce a similar sensation of heat when exposed to these kinds of irritant agents.
As an important component in many cuisines across the world, traditionally, some Asian cultures including Chinese, Indian, and Japanese, consider pungency a sixth basic taste.
Learn about the active ingredients of your favorite spicy foods below.
Capsaicin is the active component of chili peppers and is present in large quantities in the placental tissue (the seed housing) of the fruits of plants in the genus Capsicum. Pure capsaicin is a volatile, hydrophobic, colorless, odorless, crystalline to waxy compound.
Explaining why the spiciness is described as a burning and pain, the results from capsaicin contact is its chemical interaction with sensory neurons producing sensations similar to those of excessive heat or abrasive damage. While no actual direct tissue damage or chemical burn occurs, the inflammation response from exposure is believed to be the body’s reaction to nerve excitement.
Many cuisines’ foods feature the added spiciness or “heat” (piquancy) of capsaicin such as hot sauce, salsa, and beverages.
It is believed amongst diners that enjoy and indulge in capsaicin-laced foods that the simulated pain sensation releases endorphins.
Capsaicin is currently used in topical ointments and high-dose dermal patches as an analgesic to relieve the pain of neuropathy and neuralgia caused by shingles, minor aches and pains of muscles and joints associated with arthritis and strains, and fibromyalgia. Capsaicin creams are used to treat the itching and inflammation of psoriasis .
Animal and human studies show the oral intake of capsaicin may increase the production of heat by the body for a short time. Similarly, cayenne is used to regulate blood sugar levels.
The degree of heat found within a food is often measured on the Scoville scale.
The molars of mammals crush seeds and prevent germination, hence the spiciness is a deterrent to mitigate pre-dispersal seed mortality by making the plant less likely to be eaten by animals that do not help it reproduce. However, chili pepper seeds pass through the digestive tract of birds who are not deterred by the spiciness and can germinate later.
There is evidence that capsaicin also evolved as an anti-fungal agent protecting seeds from fungi attacks.
The venom of a certain tarantula species activates the same pathway of pain as is activated by capsaicin, demonstrating a shared link in both plant and animal anti-mammal defense.
Allicin is an organosulfur compound obtained from garlic, a species in the family Alliaceae. This colorless liquid has a distinctively pungent smell. This compound exhibits antibacterial and anti-fungal properties which are the garlic’s defense mechanism against attacks by pests.
Studies show that allicin may decrease blood pressure and have produce anti-inflammatory and antioxidant activities. Supplements of allicin may reduce the risk of infection from a cold, as well as, the frequency and duration of the cold.
Black Pepper (Piperine)
Black Pepper (Piperine)
Piperine is the alkaloid responsible for the pungency of black pepper. It has been used in some forms of traditional medicine for its anti-inflammatory and anti-arthritic effects in humans, as well as, as an insecticide.
Piperine was discovered in 1819 by Hans Christian Ørsted, who isolated it from the fruits of Piper nigrum, the source plant of both the black and white pepper grains.
Mustard & Horseradish (Allyl isothiocyanate)
Mustard & Horseradish (Allyl isothiocyanate)
Allyl isothiocyanate is the active ingredient and the colorless oil responsible for the pungent taste of mustard, horseradish, and wasabi. Allyl isothiocyanate or mustard oil is used principally as a flavoring agent in foods.
Allyl isothiocyanate serves the plant as a defense against herbivores. The synthetic version is used as an insecticide and bacteriocide.
Onions (syn-Propanethial S-oxide)
Gingerol, normally found as a pungent yellow oil, is the active constituent of fresh ginger and has a spicy-sweet aroma. Chemically, gingerol is a relative of capsaicin and piperine, the compounds which give chilli peppers and black pepper their respective spiciness.
Cooking ginger transforms gingerol and makes it less pungent . When ginger is dried, the gingerol becomes twice as pungent.
Gingerol has been used to reduce nausea, relieve migraine symptoms, rheumatoid arthritis and may prove to have postive results on cancerous tumors.
Some substances activate cold receptors producing a cooled, fresh or minty sensation. Believed to signal the same channels the body uses for the actual detection of cold, this phenomenon of coolness is only perceived as there is no physical temperature change.
Menthol is a natural oil derived from the perennial herb mint and has a cooling sensation. As a culinary source mint is used in teas, beverages, jellies, candies, desserts, and drinks. It was originally used as a medicinal herb to treat stomach ache, chest pains, insect bites, and congestion.
Menthol essential oil is an ingredient of many cosmetics, toiletries, and perfumes. Menthol is added to cigarettes because it blocks the bitter taste of tobacco and soothes the throat. Mint oil is also used as a room deodorizer, in aromatherapy, and as an environmentally friendly insecticide.
Vinegar, ethanol, and camphor can also simulate coolness.
Both Chinese and Indonesian cuisines include a tingling numbness caused by spices such as Sichuan pepper. These sensations, although not taste, fall into a category of Chemesthesis.
Tea, red wine, rhubarb, and unripe bananas contain tannins or calcium oxalate that cause an astringent or puckering sensation of the mucous membrane of the mouth. Astringency is can also be described as “dry”, “rough”, “harsh”, “tart”, “hard” or “styptic”.
Astringency is considered on of the six tastes in the Indian Ayurvedic tradition.
A metallic taste may be caused by food and drink, artificial sweeteners, certain medicines, dental fillings or even blood in the mouth. A metallic taste in the mouth can be a symptom of various medical conditions resulting in the distortions of the sense of taste.
Geneticists discovered a calcium receptor on the tongue that is commonly found in the gastrointestinal tract, kidneys, and brain which can detect calcium as a taste. Calcium regulation is tied to vitamin D deficiency, and chronic kidney disease.
Recent research reveals a potential taste receptor that reacts to fatty acids.
Some Japanese researchers refer to the kokumi or heartiness of foods laden with alcohol and amino acids that result in the concept and sensation of mouthfeel. Mouthfeel is the process of evaluating the flow of food through the mouth from the initial perception on the palate of the first bite, through mastication, swallowing and even includes the aftertaste.
Some of the qualities perceived may include, but are not limited to:
- Cohesiveness: Degree to which the sample deforms before rupturing when biting with molars.
- Density: Compactness of cross section of the sample after biting completely through with the molars.
- Dryness: Degree to which the sample feels dry in the mouth.
- Fracturability: encompasses crumbliness, crispiness, crunchiness, and brittleness.
- Graininess: Degree to which a sample contains small grainy particles.
- Gumminess: Energy required to disintegrate a semi-solid food to a state ready for swallowing.
- Hardness: Force required to deform the product to given distance, i.e., force to compress between molars, bite through with incisors, compress between tongue and palate.
- Heaviness: Weight of product perceived when first placed on tongue.
- Moisture absorption: Amount of saliva absorbed by product.
- Moisture release: Amount of wetness/juiciness released from sample.
- Mouthcoating: Type and degree of coating in the mouth after mastication (for example, fat/oil).
- Roughness: Degree of abrasiveness of product’s surface perceived by the tongue.
- Slipperiness: Degree to which the product slides over the tongue.
- Smoothness: Absence of any particles, lumps, bumps, etc., in the product.
- Uniformity: Degree to which the sample is even throughout; homogeneity.
- Uniformity of Bite: Evenness of force through bite.
- Uniformity of Chew: Degree to which the chewing characteristics of the product are even throughout mastication.
- Viscosity: Force required to draw a liquid from a spoon over the tongue.
- Wetness: Amount of moisture perceived on product’s surface.
Temperature can be an essential element of the taste experience depending on culture or preference. Food and drink served cold, if traditionally served hot, may be considered distasteful. For example, most alcoholic beverages, are usually thought best when served cold, while soups, with exceptions, are usually served hot.