the sense of taste refers to the ability of the

8/14/2019 The Sense of Taste Refers to the Ability of The

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TASTE

The sense of taste refers to the ability of the taste organs to perceive and

recognize the five basic taste sweet, sour, bitter, salty and unami. The

components of food responsible for taste are non-volatile compounds.

They must be in solution or dissolve in saliva to produce the tasteresponse. Taste is sensed by the buds which lie mostly in grooves around

little projections on the upper surface of the tongue.

It refers to the ability to detect the flavor of substances such as food,

certain minerals, andpoisons.

TYPES OF TASTE:

1. BITTERNESSBitterness is the taste which detects bases. Bitterness is the most sensitiveof the tastes, and is perceived by many to be unpleasant, sharp, ordisagreeable. Common bitter foods and beverages include coffee,unsweetened chocolate,bitter melon,beer,bitters, olives, citrus peel. Themost bitter substance known is the synthetic chemical denatonium, whichhas an index of 1,000.Research has shown that TAS2Rs (taste receptors, type 2, also known as

T2Rs) such as TAS2R38 coupled to the G protein gustducin areresponsible for the human ability to taste bitter substances. Researchersuse two synthetic substances, phenylthiocarbamide (PTC) and 6-n-

propylthiouracil (PROP) to study the genetics of bitter perception.Quinine, the anti-malarial prophylactic, is also known for its bitter tasteand is found in tonic water. Bitter taste is sensed at the back side of thetongue.

2. SALTINESS

Saltiness is a taste produced primarily by the presence of sodium ions.Other ions of the alkali metals group also taste salty. Salty taste is sensedat the edges of the tongue

3. SOURNESS
http://en.wikipedia.org/wiki/Flavorhttp://en.wikipedia.org/wiki/Foodhttp://en.wikipedia.org/wiki/Mineralshttp://en.wikipedia.org/wiki/Poisonhttp://en.wikipedia.org/wiki/Coffeehttp://en.wikipedia.org/wiki/Chocolatehttp://en.wikipedia.org/wiki/Bitter_melonhttp://en.wikipedia.org/wiki/Beerhttp://en.wikipedia.org/wiki/Bittershttp://en.wikipedia.org/wiki/Olive_(fruit)http://en.wikipedia.org/wiki/Peel_(fruit)http://en.wikipedia.org/wiki/Denatoniumhttp://en.wikipedia.org/wiki/TAS2R38http://en.wikipedia.org/wiki/G_proteinhttp://en.wikipedia.org/wiki/Gustducinhttp://en.wikipedia.org/wiki/Phenylthiocarbamidehttp://en.wikipedia.org/wiki/Propylthiouracilhttp://en.wikipedia.org/wiki/Propylthiouracilhttp://en.wikipedia.org/wiki/Geneticshttp://en.wikipedia.org/wiki/Sodium_ionhttp://en.wikipedia.org/wiki/Alkali_metalshttp://en.wikipedia.org/wiki/Foodhttp://en.wikipedia.org/wiki/Mineralshttp://en.wikipedia.org/wiki/Poisonhttp://en.wikipedia.org/wiki/Coffeehttp://en.wikipedia.org/wiki/Chocolatehttp://en.wikipedia.org/wiki/Bitter_melonhttp://en.wikipedia.org/wiki/Beerhttp://en.wikipedia.org/wiki/Bittershttp://en.wikipedia.org/wiki/Olive_(fruit)http://en.wikipedia.org/wiki/Peel_(fruit)http://en.wikipedia.org/wiki/Denatoniumhttp://en.wikipedia.org/wiki/TAS2R38http://en.wikipedia.org/wiki/G_proteinhttp://en.wikipedia.org/wiki/Gustducinhttp://en.wikipedia.org/wiki/Phenylthiocarbamidehttp://en.wikipedia.org/wiki/Propylthiouracilhttp://en.wikipedia.org/wiki/Propylthiouracilhttp://en.wikipedia.org/wiki/Geneticshttp://en.wikipedia.org/wiki/Sodium_ionhttp://en.wikipedia.org/wiki/Alkali_metalshttp://en.wikipedia.org/wiki/Flavor


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Sourness is the taste that detects acidity. The sourness of substances israted relative to dilute hydrochloric acid, which has a sourness index of 1.By comparison, tartaric acid has a sourness index of 0.7, citric acid anindex of 0.46, and carbonic acid an index of 0.06. The mechanism fordetecting sour taste is similar to that which detects salt taste. Hydrogen ionchannels detect the concentration of hydronium ions (H3O

+ ions) that are

formed from acids and water.The most common food group that contains naturally sour foods is thefruit, with examples such as the lemon, grape, orange, and sometimes themelon. Wine also usually has a sour tinge to its flavor. If not keptcorrectly, milkcan spoil and contain a sour taste. Sour taste is sensed at theedges of the tongue

4. SWEETNESS

Sweetness, usually regarded as a pleasurable sensation, is produced by the

presence ofsugars, some proteins and a few other substances. Sweetness isoften connected to aldehydes and ketones, which contain a carbonyl group.Sweetness is detected by a variety ofG protein coupled receptors coupledto the G proteingustducin found on the taste buds. At least two differentvariants of the "sweetness receptors" need to be activated for the brain toregister sweetness. Taste detection thresholds for sweet substances arerated relative to sucrose, which has an index of 1.The average humandetection threshold for sucrose is 10 millimoles per litre. For lactose it is

30 millimoles per litre, with a sweetness index of 0.3. Sweet is sensed atthe tip of the tongue.

5. UMAMI

Umami is the name for the taste sensation produced by compounds such asglutamate, and are commonly found in fermented and aged foods. InEnglish, it is also described as "meatiness", "relish", or "savoriness". The

Japanese word comes from umai ( ?) for delicious, keen, or nice.Umami is now the term commonly used by taste scientists.

Humans have taste receptors specifically for the detection of the aminoacids, e.g., glutamic acid. Amino acids are the building blocks ofproteinsand are found in meats, cheese, fish, and other protein-heavy foods.
http://en.wikipedia.org/wiki/Acidhttp://en.wikipedia.org/wiki/Tartaric_acidhttp://en.wikipedia.org/wiki/Citric_acidhttp://en.wikipedia.org/wiki/Carbonic_acidhttp://en.wikipedia.org/wiki/Ion_channelshttp://en.wikipedia.org/wiki/Ion_channelshttp://en.wikipedia.org/wiki/Hydronium_ionhttp://en.wikipedia.org/wiki/Fruithttp://en.wikipedia.org/wiki/Lemonhttp://en.wikipedia.org/wiki/Grapehttp://en.wikipedia.org/wiki/Orange_(fruit)http://en.wikipedia.org/wiki/Melonhttp://en.wikipedia.org/wiki/Winehttp://en.wikipedia.org/wiki/Milkhttp://en.wikipedia.org/wiki/Sugarhttp://en.wikipedia.org/wiki/Aldehydehttp://en.wikipedia.org/wiki/Ketonehttp://en.wikipedia.org/wiki/Carbonyl_grouphttp://en.wikipedia.org/wiki/G_protein_coupled_receptorhttp://en.wikipedia.org/wiki/G_proteinhttp://en.wikipedia.org/wiki/Gustducinhttp://en.wikipedia.org/wiki/Taste_budhttp://en.wikipedia.org/wiki/Sucrosehttp://en.wikipedia.org/wiki/Lactosehttp://en.wikipedia.org/wiki/Glutamatehttp://en.wikipedia.org/wiki/Fermentation(food)http://en.wikipedia.org/wiki/Japanese_languagehttp://en.wikipedia.org/wiki/Help:Installing_Japanese_character_setshttp://en.wikipedia.org/wiki/Amino_acidhttp://en.wikipedia.org/wiki/Amino_acidhttp://en.wikipedia.org/wiki/Glutamic_acidhttp://en.wikipedia.org/wiki/Proteinshttp://en.wikipedia.org/wiki/Acidhttp://en.wikipedia.org/wiki/Tartaric_acidhttp://en.wikipedia.org/wiki/Citric_acidhttp://en.wikipedia.org/wiki/Carbonic_acidhttp://en.wikipedia.org/wiki/Ion_channelshttp://en.wikipedia.org/wiki/Ion_channelshttp://en.wikipedia.org/wiki/Hydronium_ionhttp://en.wikipedia.org/wiki/Fruithttp://en.wikipedia.org/wiki/Lemonhttp://en.wikipedia.org/wiki/Grapehttp://en.wikipedia.org/wiki/Orange_(fruit)http://en.wikipedia.org/wiki/Melonhttp://en.wikipedia.org/wiki/Winehttp://en.wikipedia.org/wiki/Milkhttp://en.wikipedia.org/wiki/Sugarhttp://en.wikipedia.org/wiki/Aldehydehttp://en.wikipedia.org/wiki/Ketonehttp://en.wikipedia.org/wiki/Carbonyl_grouphttp://en.wikipedia.org/wiki/G_protein_coupled_receptorhttp://en.wikipedia.org/wiki/G_proteinhttp://en.wikipedia.org/wiki/Gustducinhttp://en.wikipedia.org/wiki/Taste_budhttp://en.wikipedia.org/wiki/Sucrosehttp://en.wikipedia.org/wiki/Lactosehttp://en.wikipedia.org/wiki/Glutamatehttp://en.wikipedia.org/wiki/Fermentation(food)http://en.wikipedia.org/wiki/Japanese_languagehttp://en.wikipedia.org/wiki/Help:Installing_Japanese_character_setshttp://en.wikipedia.org/wiki/Amino_acidhttp://en.wikipedia.org/wiki/Amino_acidhttp://en.wikipedia.org/wiki/Glutamic_acidhttp://en.wikipedia.org/wiki/Proteins


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Examples of food containing glutamate (and thus strong in umami) arebeef, lamb,parmesan, and roquefortcheese as well as soy sauce and fishsauce.

The additive monosodium glutamate (MSG) produces a strong umami.Umami is also provided by the nucleotides 5-inosine monophosphate(IMP) and 5-guanosine monophosphate (GMP). These are naturally

present in many protein-rich foods. Some umami taste buds respondspecifically to glutamate in the same way that "sweet" ones respond tosugar. Glutamate binds to a variant of G protein coupled glutamatereceptors.

EXAMPLES OF TASTANT MOLECULES

SUGARS

Sucrose C12H22O11

Fructose C6H12O6

Glucose C6H12O6

Lactose C12H22O11

SALT Table Salt NaCl
http://en.wikipedia.org/wiki/Parmesanhttp://en.wikipedia.org/wiki/Roqueforthttp://en.wikipedia.org/wiki/Cheesehttp://en.wikipedia.org/wiki/Soy_saucehttp://en.wikipedia.org/wiki/Fish_saucehttp://en.wikipedia.org/wiki/Fish_saucehttp://en.wikipedia.org/wiki/Monosodium_glutamatehttp://en.wikipedia.org/wiki/Nucleotidehttp://en.wikipedia.org/wiki/Inosinic_acidhttp://en.wikipedia.org/wiki/Guanosine_monophosphatehttp://en.wikipedia.org/wiki/G_protein_coupled_receptorhttp://en.wikipedia.org/wiki/G_protein_coupled_receptorhttp://www.edinformatics.com/math_science/science_of_cooking/sucrose.htmhttp://www.edinformatics.com/math_science/science_of_cooking/fructose.htmhttp://www.edinformatics.com/math_science/science_of_cooking/glucose.htmhttp://www.edinformatics.com/math_science/science_of_cooking/lactose.htmhttp://www.edinformatics.com/math_science/science_of_cooking/nacl.htmhttp://en.wikipedia.org/wiki/Parmesanhttp://en.wikipedia.org/wiki/Roqueforthttp://en.wikipedia.org/wiki/Cheesehttp://en.wikipedia.org/wiki/Soy_saucehttp://en.wikipedia.org/wiki/Fish_saucehttp://en.wikipedia.org/wiki/Fish_saucehttp://en.wikipedia.org/wiki/Monosodium_glutamatehttp://en.wikipedia.org/wiki/Nucleotidehttp://en.wikipedia.org/wiki/Inosinic_acidhttp://en.wikipedia.org/wiki/Guanosine_monophosphatehttp://en.wikipedia.org/wiki/G_protein_coupled_receptorhttp://en.wikipedia.org/wiki/G_protein_coupled_receptorhttp://www.edinformatics.com/math_science/science_of_cooking/sucrose.htmhttp://www.edinformatics.com/math_science/science_of_cooking/fructose.htmhttp://www.edinformatics.com/math_science/science_of_cooking/glucose.htmhttp://www.edinformatics.com/math_science/science_of_cooking/lactose.htmhttp://www.edinformatics.com/math_science/science_of_cooking/nacl.htm


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BITTER

TASTANT

S

Denatonium C21H29N2OC7H5O2

Caffeine C8H10N4O2

Quinine C20H24N2O2

PTC

(Phenylthiourea

)

C7H8N2S

Humulone

(beer)C21H30O5

UMAMIAspartate C4H7NO4
http://www.edinformatics.com/math_science/science_of_cooking/denatorium.htmhttp://www.edinformatics.com/math_science/science_of_cooking/caffeine.htmhttp://www.edinformatics.com/math_science/science_of_cooking/quinine.htmhttp://www.edinformatics.com/math_science/science_of_cooking/ptc.htmhttp://www.edinformatics.com/math_science/science_of_cooking/ptc.htmhttp://www.edinformatics.com/math_science/science_of_cooking/ptc.htmhttp://www.edinformatics.com/math_science/science_of_cooking/humulone.htmhttp://www.edinformatics.com/math_science/science_of_cooking/humulone.htmhttp://www.edinformatics.com/math_science/science_of_cooking/aspartame.htmhttp://www.edinformatics.com/math_science/science_of_cooking/denatorium.htmhttp://www.edinformatics.com/math_science/science_of_cooking/caffeine.htmhttp://www.edinformatics.com/math_science/science_of_cooking/quinine.htmhttp://www.edinformatics.com/math_science/science_of_cooking/ptc.htmhttp://www.edinformatics.com/math_science/science_of_cooking/ptc.htmhttp://www.edinformatics.com/math_science/science_of_cooking/ptc.htmhttp://www.edinformatics.com/math_science/science_of_cooking/humulone.htmhttp://www.edinformatics.com/math_science/science_of_cooking/humulone.htmhttp://www.edinformatics.com/math_science/science_of_cooking/aspartame.htm


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GOOD TO KNOW:

Sweet - usually indicates energy rich nutrients

Umami - the taste of amino acids (e.g. meat broth or aged cheese)

Salty - allows modulating diet for electrolyte balance

Sour - typically the taste of acids Bitter - allows sensing of diverse natural toxins

We have almost 10,000 taste buds inside our mouths; even on the roofs ofour mouths.

Insects have the most highly developed sense of taste. They have tasteorgans on their feet, antennae, and mouthparts.

Fish can taste with their fins and tail as well as their mouth.

In general, girls have more taste buds than boys.

Taste is the weakest of the five senses.

Taste Substance Threshold for tasting

Salty NaCl 0.01 M

Sour HCl 0.0009 M

Sweet Sucrose 0.01 M

Bitter Quinine 0.000008 M

Umami Glutamate 0.0007 M

FACTORS AFFECTING TASTE:

TEMPERATURE;


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Sugared drink appears sweeter when hot than when cold.Lemon drink taste more sour when it is hot than when cold.Coffee and tea appears to be more bitter when cold then hot.

TIME:

Salt on the tongue is sensed in a fraction of seconds, whereas a bittersubstance may require a full second after it contacts the tongue before it issensed by the taste buds.

Other factors include:

Aging Color/vision impairments

Hormonal influences

Genetic variations; see Phenylthiocarbamide

Oral temperature

Drugs and chemicals

Natural Substances (such as Miracle fruit, which temporarily makessour foods taste sweeter)

Lemonade, for example, is made by combining lemon juice (sour),sugar (sweet), and water. Without the sugar, the lemon juicewatermixture tastes very sour. The more sugar is added, the less sour theresult tastes. Another example is tonic water, made by combining

quinine (extremely bitter), sugar (sweet), and water. The bitternesscauses many people to not perceive tonic water as sweet, even though itcontains as much sugar as an ordinary soft drink.

TASTE AND THE TONGUE
http://en.wikipedia.org/wiki/Phenylthiocarbamidehttp://en.wikipedia.org/wiki/Miracle_fruithttp://en.wikipedia.org/wiki/Phenylthiocarbamidehttp://en.wikipedia.org/wiki/Miracle_fruit


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Taste cells throughout the mouthand throat cluster together to form taste buds. Isolated taste buds arescattered on the surface of the palate and throat, but on the tongue they aregrouped in specialized structures called papillae:

mushroom-shaped fungiform papillae in the front of the tongue, leaf-shaped foliate papillae protruding from the sides, and circumvallate

papillae arrayed in a chevron at the back of the tongue. The tips of the tastecells reach toward a tiny opening on the tongue - the gustatory pore -through which food chemicals can fall. Nerve endings for the taste systemand for the touch/temperature/pain system surround the base of the taste

bud cells.

FROM TONGUE TO BRAIN


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Three nerves bring taste messages to the brainstem: the facial nerve, shown in

the picture above, which brings messages from the anterior two-thirds of the

tongue; the hypoglossal nerve, which brings messages from the posterior

tongue; and the glossopharyngeal nerve, which brings messages from the throat

area and the palate. The nerve carrying messages from the

touch/temperature/pain system is called the trigeminal nerve. All of these

nerves bring their messages to the brainstem, where they combine their signals

in areas of the brainstem that are involved with arousal (for example from

sleep), As taste messages move further through the brain, they join up with

smell messages to give the sensation of flavor.

the sense of taste refers to the ability of the

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