Primary taste sensations

In humans, sensors for taste are collected in structures known as taste buds. Your mouth contains about 10,000 taste buds the majority are located at various sites on your tongue. The remainder are found in the pharynx, epiglottis, and at the entrance to the esophagus. Each taste bud senses and reacts to all five primary taste sensations. I want to dispel an old, untrue but widely held belief that different parts of the tongue are devoted to different tastes. It just isn t so, regardless of what you might have been taught or otherwise have been led to believe. 

There are five primary taste sensations salty, sour, sweet, bitter, and umami (or savory). The receptors for these tastes are encoded in a few dozen genes in the human genome. These are expressed in taste buds. 

Indeed, potatoes are rather neutral in flavor, but they contain typical taste and odor substances. Their overall acceptance in the U.S. and in Europe is very high Q ), higher than for many other commodities. A bland food would never obtain such a high acceptability. However, according to Burr (2) none of the four primary taste sensations of sour, solty, sweet and bitter is ordinarily perceptible in normal cooked potatoes. 

Potato taste is not characterized by one of the primary taste sensations. Especially sweet, sour or bitter notes are considered off-flavors. However, free amino acids and 5 -nucleotides are important compounds that convey an agreeable basic taste to potato products. The amino acids occur naturally in free form the 5 -nucleotides are liberated during the heat preparation of potatoes by a specific enzymatic degradation of RNA. Starch forms a matrix for all potato preparations. Although it is tasteless, is has an influence on taste quality due to textural characteristics, and due to its pronounced capability to form stable complexes with flavor compounds either in a thermal gradient or under isothermal conditions. 

Taste receptors reside within taste buds on the tongue, the larynx, and the palate. There are four primary taste sensations sour, sweet, bitter, and salty. By mixing these primary taste sensations, the brain can identify many specific tastes (analogous to primary color mixing). Impulses from the taste buds are carried through the facial, glossopharyngeal, and vagus nerves (cranial nerves VII, IX, and X, respectively) to the brain. Taste is modified by the presence of odor, and in the absence of olfactory ability, taste is virtually eliminated. 

There are five primary taste sensations including sweet (carbohydrate based molecules), sour (acidic concentration), salty (sodium chloride), bitter (quinine and other basic functionalities) and umami (salts of glutamic acid). The human tongue does not discriminate every chemical substance composing a flavor it decomposes the taste of foodstuffs into the five basic taste qualities, instead. A single taste bud contains 50-100 taste cells representing all 5 taste sensation. An adult has about 9000 taste buds. 

With the exception of the four primary taste sensations— sweet, bitter, salty, and sour—food flavors are the result of our sense of smell. Today, chemists can make chemicals in the laboratory which alone or in various combinations can imitate many of the natural food flavors. These are synthetic flavors. In many cases the synthetic flavors are superior to natural flavors in terms of (1) withstanding processing, (2) cost, (3) availability, and (4) consistent quality. Synthetic flavors may be substances that are prepared in the laboratory but chemically identical to those found in nature, or substances prepared in the laboratory which as yet have not been found to occur in nature but which produce familiar aromas. 

A century ago, Fick proposed the concept of four primary tastes, namely, sweet, salty, sour, and bitter. It has since been found that taste sensations are not describable by a single collection of discrete primaries. Electrophysiological studies of afierent taste-units in the chorda tympani and glossophyrangeal nerves have revealed that a continuous spectrum of gustation may be based on these four taste elements. Furthermore, the intensities of the tastes that we commonly experience are due not only to gustatory sensations but also to tactile, hot and cold, and, above all, olfactory sensations. The complexities of taste studies are such that, unless one of the taste modalities is singled out for study, there is very little hope of success. 

Sweetness is an important and easily identifiable characteristic of glucose- and fructose-containing sweeteners. The sensation of sweetness has been extensively studied.80-82 Shallenberger83 defines sweetness as a primary taste. He furthermore asserts that no two substances can have the same taste. Thus, when compared to sucrose, no other sweetener will have the unique properties of sweetness onset, duration and intensity of sucrose. It is possible to compare the relative sweetness values of various sweeteners, as shown in Table 21.17,84 but it must be kept in mind that these are relative values. There will be variations in onset, which is a function of the chirality of the sweetener,85 variations in duration, which is a function of the molecular weight profile and is impacted by the viscosity, and changes in intensity, which is affected by... 

Taste is a complex combination of sensations including gustation, olfaction, tactility, and responses to heat and cold. In humans the sensation of taste is confined primarily to the dorsal face of the tongue, the soft palate, the epiglottis, and parts of the gullet. In children, however, the taste receptors are distributed over larger areas of the mouth." Basically there are four so-called primary tastes sour, bitter, salty. 

Sensation provides the input to the system. The sources of sensory information can be outside your body through one of the five primary senses sight, sound, taste, smell, and touch. The source of information can also be inside your body. The nervous system receives and monitors information such as your blood pressure, blood sugar, and blood oxygen level. 

Taste consists of four primary sensations sweet, sour, bitter, and salty. Correspondingly, there are four... 

Taste is mainly a function of the taste buds, of which there are, approximately, 10,000 in the tongue with a few on the soft palate, inner surface of the cheek, pharynx, and epiglottis of the larynx [15]. There are live primary sensations of taste sweet, sour, salty, bitter, and umami. Table 6.3 provides various examples of these. 

Finally, it is important to note that there are hundreds of different types of tastes that are the result of varying degrees of stimulation of two, three, four, or live of the primary sensations at the same time. 

Unlike taste, it has not been easy to classify smells into primary sensations. On the basis of psychological tests and action potential stndies, seven different primary classes of olfactory stimnlants have been identihed [16] ... 

Flavorings—These are the substances that stimulate the senses of taste and/or smell. With the exception of the four primary sensations—sweet, bitter, salty, and sour— flavor characteristics are the result of our perception of odor the difference between flavor and fragrance is in large part only a semantic distinction. Thus, a substance that provides an odor in perfumes may also be used to add flavoring to a food. 

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