Sour vs. Sweet

Main Difference

The main difference between Sour and Sweet is that the Sour is a sense that detects types of chemicals that touch the tongue and Sweet is a basic taste.

• Sour

  Taste, gustatory perception, or gustation is one of the five traditional senses that belongs to the gustatory system.

  Taste is the sensation produced when a substance in the mouth reacts chemically with taste receptor cells located on taste buds in the oral cavity, mostly on the tongue. Taste, along with smell (olfaction) and trigeminal nerve stimulation (registering texture, pain, and temperature), determines flavors of food or other substances. Humans have taste receptors on taste buds (gustatory calyculi) and other areas including the upper surface of the tongue and the epiglottis. The gustatory cortex is responsible for the perception of taste.

  The tongue is covered with thousands of small bumps called papillae, which are visible to the naked eye. Within each papilla are hundreds of taste buds. The exception to this is the filiform papillae that do not contain taste buds. There are between 2000 and 5000 taste buds that are located on the back and front of the tongue. Others are located on the roof, sides and back of the mouth, and in the throat. Each taste bud contains 50 to 100 taste receptor cells.

  The sensation of taste includes five established basic tastes: sweetness, sourness, saltiness, bitterness, and savoriness. Scientific experiments have proven that these five tastes exist and are distinct from one another. Taste buds are able to distinguish between different tastes through detecting interaction with different molecules or ions. Sweet, savory, and bitter tastes are triggered by the binding of molecules to G protein-coupled receptors on the cell membranes of taste buds. Saltiness and sourness are perceived when alkali metal or hydrogen ions enter taste buds, respectively.

  The basic tastes contribute only partially to the sensation and flavor of food in the mouth—other factors include smell, detected by the olfactory epithelium of the nose; texture, detected through a variety of mechanoreceptors, muscle nerves, etc.; temperature, detected by thermoreceptors; and “coolness” (such as of menthol) and “hotness” (pungency), through chemesthesis.

  As taste senses both harmful and beneficial things, all basic tastes are classified as either aversive or appetitive, depending upon the effect the things they sense have on our bodies. Sweetness helps to identify energy-rich foods, while bitterness serves as a warning sign of poisons.

  Among humans, taste perception begins to fade around 50 years of age because of loss of tongue papillae and a general decrease in saliva production. Humans can also have distortion of tastes through dysgeusia. Not all mammals share the same taste senses: some rodents can taste starch (which humans cannot), cats cannot taste sweetness, and several other carnivores including hyenas, dolphins, and sea lions, have lost the ability to sense up to four of their ancestral five taste senses.

• Sweet

  Sweetness is a basic taste most commonly perceived when eating foods rich in sugars. Sweet tastes are regarded as a pleasurable experience, except perhaps in excess.

  Fructose is sweeter than glucose and sucrose. This has made possible the production of sugar syrups with the sweetness and certain other properties of sucrose starting from starch.

  In addition to sugars like sucrose, many other chemical compounds are sweet, including aldehydes, ketones, and sugar alcohols. Some are sweet at very low concentrations, allowing their use as non-caloric sugar substitutes. Such non-sugar sweeteners include saccharin and aspartame. Other compounds, such as miraculin, may alter perception of sweetness itself.

  The chemosensory basis for detecting sweetness, which varies between both individuals and species, has only begun to be understood since the late 20th century. One theoretical model of sweetness is the multipoint attachment theory, which involves multiple binding sites between a sweetness receptor and a sweet substance.

  Studies indicate that responsiveness to sugars and sweetness has very ancient evolutionary beginnings, being manifest as chemotaxis even in motile bacteria such as E. coli. Newborn human infants also demonstrate preferences for high sugar concentrations and prefer solutions that are sweeter than lactose, the sugar found in breast milk. Sweetness appears to have the highest taste recognition threshold, being detectable at around 1 part in 200 of sucrose in solution. By comparison, bitterness appears to have the lowest detection threshold, at about 1 part in 2 million for quinine in solution. In the natural settings that human primate ancestors evolved in, sweetness intensity should indicate energy density, while bitterness tends to indicate toxicity The high sweetness detection threshold and low bitterness detection threshold would have predisposed our primate ancestors to seek out sweet-tasting (and energy-dense) foods and avoid bitter-tasting foods. Even amongst leaf-eating primates, there is a tendency to prefer immature leaves, which tend to be higher in protein and lower in fibre and poisons than mature leaves. The ‘sweet tooth’ thus has an ancient evolutionary heritage, and while food processing has changed consumption patterns, human physiology remains largely unchanged.

• Sweet (adjective)

  having the pleasant taste characteristic of sugar or honey; not salt, sour, or bitter

  “a cup of hot sweet tea”

• Sweet (adjective)

  (of air, water, or food) fresh, pure, and untainted

  “lungfuls of the clean, sweet air”

• Sweet (adjective)

  smelling pleasant like flowers or perfume; fragrant

  “a bunch of sweet-scented flowers”

• Sweet (adjective)

  pleasing in general; delightful

  “it was the sweet life he had always craved”

• Sweet (adjective)

  highly satisfying or gratifying

  “some sweet, short-lived revenge”

• Sweet (adjective)

  used in expressions of assent or approval

  “Yeah, I’d like to come to the party. Sweet!”

• Sweet (adjective)

  working, moving, or done smoothly or easily

  “the sweet handling of this motorcycle”

• Sweet (adjective)

  (of sound) melodious or harmonious

  “the sweet notes of the flute”

• Sweet (adjective)

  denoting music, especially jazz, played at a steady tempo without improvisation.

• Sweet (adjective)

  (of a person or action) pleasant and kind or thoughtful

  “it was sweet of you to come”

  “a very sweet nurse came along”

• Sweet (adjective)

  charming and endearing

  “a sweet little cat”

• Sweet (adjective)

  infatuated or in love with

  “she seemed quite sweet on him”

• Sweet (adjective)

  dear; beloved

  “my sweet love”

• Sweet (adjective)

  used as a respectful form of address

  “go to thy rest, sweet sir”

• Sweet (adjective)

  used for emphasis in various phrases and exclamations

  “What had happened? Sweet nothing”

• Sweet (noun)

  a small shaped piece of confectionery made with sugar

  “a bag of sweets”

• Sweet (noun)

  a sweet dish forming a course of a meal; a pudding or dessert.

• Sweet (noun)

  used as an affectionate form of address

  “hello, my sweet”

• Sweet (noun)

  the sweet part or element of something

  “you have had the bitter, now comes the sweet”

• Sweet (noun)

  the pleasures or delights found in something

  “the sweets of office”