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== The generic purpose of taste perception ==
<div style='text-align:justify;'>The majority of taste stimuli are non-volatile, saliva-soluble hydrophilic molecules. Examples include salts like NaCl, which are vital for maintaining electrolyte balance, essential amino acids like glutamate, which are required for protein synthesis, carbohydrates like glucose, which are required for energy, and acids like citric acid, which determine the taste of many foods (oranges, in the case of citrate). Plant alkaloids can be dangerous, including bitter-tasting compounds like atropine, quinine, and strychnine. Unless one "acquires a taste" for the chemical, as with quinine in tonic water, putting bitter substances in the mouth typically discourages intake.<ref>Purves D, Augustine GJ, Fitzpatrick D, Katz LC, LaMantia A-S, McNamara JO, et al. Taste Perception in Humans. 2001 [cited 2022 Oct 9]; Available from: https://www.ncbi.nlm.nih.gov/books/NBK10833/</ref><br/>The taste system encodes information about the quantity as well as the identity of stimuli. Generally speaking, the perceived intensity of flavour increases with increasing stimulus concentration. However, the majority of ingested tastants have fairly high threshold concentrations. For instance, the threshold value for sucrose is 20 mM, 10 mM for salt (NaCl), and roughly 2 mM for citric acid. Taste cells may only react to relatively high quantities of these necessary elements to promote an optimal intake since the body needs substantial concentrations of salt and carbs. The ability to identify potentially harmful substances (such bitter-tasting plant components) at far lower quantities is clearly helpful for the taste system. As a result, the threshold value for strychnine is 0.0001 mM and 0.008 mM for quinine. Gustatory sensitivity decreases with age, just as olfaction. Adults typically season food with more salt and spices than do kids. The decreased sensitivity to salt can be troublesome for older adults with issues with electrolyte and/or fluid balance. Unfortunately, there isn't presently a secure and reliable NaCl alternative.<ref>Purves D, Augustine GJ, Fitzpatrick D, Katz LC, LaMantia A-S, McNamara JO, et al. Taste Perception in Humans. 2001 [cited 2022 Oct 9]; Available from: https://www.ncbi.nlm.nih.gov/books/NBK10833/</ref></div>
<div style='text-align:justify;'>
'''Other Locations with Taste Receptors:''' There are numerous locations in the body where taste receptors can be discovered. Examples: The trachea and bronchi's cilia and smooth muscle cells include bitter receptors (T2Rs), which are likely used to expel inhaled irritants. The duodenum contains sweet receptors (T1Rs). In response to carbohydrates entering the duodenum, the cells release incretins. These lead to an increase in insulin secretion from the pancreas' beta cells. Therefore, rather than just detecting taste, "taste" receptors appear to also be able to sense substances in the surroundings.<ref>Kimball JW. 15.9G: Taste. Published 2022. Accessed November 8, 2022. https://bio.libretexts.org/Bookshelves/Introductory_and_General_Biology/Book%3A_Biology_(Kimball)/15%3A_The_Anatomy_and_Physiology_of_Animals/15.09%3A_Senses/15.9G%3A_Taste</ref></div>
== Misconceptions about taste perception ==
<div style='text-align:justify;'>
Two frequent misunderstandings about taste perception exist. Which are as follows:
<ol>
<li>Rigid demarcation of certain areas on the tongue for each taste(15). The proposition that sweet is perceived at the tip of the tongue, salt along posterolateral edges, sour along mediolateral edges and bitter on theback of the tongue is initially proposed in 1901 by DeiterHanig. He has measured taste thresholds for NaCL, sucrose, quinine and hydrochloric acid (HCl). The proposition does not negate that rest of the areas are incapable of perceiving certain taste. It merely indicates that certain areas are more sensitive to perceive certain taste. However, certain areas having more sensitivity helps to adjust the behaviour of a person for intake of certain food item etc., e.g.
<ol type="a">
<li>Sweet taste: Since sweet substances provide pleasurable sensations, the tip of the tongue is especially sensitive to them, and input from this area stimulates feeding behaviours such mouth movements, salivary production, insulin release, and swallowing.</li>
<li>The back of the tongue does indeed respond to bitter chemicals the best. Bitter chemicals that activate this region cause the tongue to protrude and other defensive reflexes that stop swallowing.</li>
<li>Sour substances cause grimaces, puckering reactions, and a lot of salivation to be secreted to mask the tastant.<ref>Purves D, Augustine GJ, Fitzpatrick D, Katz LC, LaMantia A-S, McNamara JO, et al. Taste Perception in Humans. 2001 [cited 2022 Oct 9]; Available from: https://www.ncbi.nlm.nih.gov/books/NBK10833/</ref></li></ol></li>
<li>The idea that there are only four "basic" tastes—salt, sweet, sour, and bitter—is another fallacy about taste perception.If this were the case, then any combination of these "primaries" could represent any taste. These four tastes do represent unique sensations, yet it is evident that this categorization is constrained. Additional tastes that people feel include astringency (from cranberries and tea), pungency (from hot pepper and ginger), fattiness, starchiness, and various metallic tastes (to name but a few). But none of this fall under any of these four groups. Additionally, in some cultures, certain tastes are regarded as "primary." For instance, the Japanese believe that the tastes of monosodium glutamate differs from that of salt and even give it a new name ("umami," which translates to "delicious"). Last but not least, combining different compounds can produce completely different tastes. It is possible to estimate the number of scents that are perceived (about 10,000), but due to these uncertainties, it is challenging to determine the number of tastes. There is no obvious connection between "basic" perceptual classes and the cellular and molecular machinery of sensory transduction in either taste or olfaction.<ref>Purves D, Augustine GJ, Fitzpatrick D, Katz LC, LaMantia A-S, McNamara JO, et al. Taste Perception in Humans. 2001 [cited 2022 Oct 9]; Available from: https://www.ncbi.nlm.nih.gov/books/NBK10833/</ref></li></ol></div>
== References ==
== References ==