Changes

==The Five Flavors==

==The Five Flavors==

Sour flavors are generally produced by acids, and different acids produce different acidic flavors. Some familiar sour flavors are vinegar (acetic acid), sour milk (lactic acid), citrus fruit (citric acid), apples (malic acid) and wine (tartaric acid) (Reineccius). Salty flavors are most commonly associated with the mineral of the same name (sodium chloride), however most low molecular weight salts (ammonium chloride, potassium chloride, lithium chloride, sodium bromide, ammonium bromide, sodium iodide and lithium iodide) have a salty taste (Pyke). Less is known about sweet and bitter substances. There seems to be no relationship between organic functional groups and sweet flavor (as almost every class of compound has a member which tastes sweet), yet at the same time the chemistry is very specific. For example, saccharine, Figure 1, is 300 times sweeter than sugar (sucrose), however if the hydrogen bonded to the nitrogen is replaced with a methyl group, all flavor sensation disappears (Pyke). Likewise, bitter sensations are difficult to classify, though many plant-derived molecules which interact with the brain such as caffeine and nicotine (Reineccius), as well as large molecular weight ionic salts such as cesium chloride, rubidium bromide and potassium iodide (Pyke) produce bitter tastes.

Sour flavors are generally produced by [[acid]]s, and different acids produce different acidic flavors. Some familiar sour flavors are [[vinegar]] ([[acetic acid]]), sour [[milk]] ([[lactic acid]]), [[citrus]] [[fruit]] ([[citric acid]]), [[apple]]s ([[malic acid]]) and [[wine]] ([[tartaric acid]]) (Reineccius).

 

[[Salt]]y flavors are most commonly associated with the mineral of the same name (sodium chloride), however most low [[molecular weight]] salts ([[ammonium]] [[chlorine|chloride]], [[potassium]] chloride, [[lithium]] chloride, [[sodium]] [[bromine|bromide]], ammonium bromide, sodium [[iodine|iodide]] and lithium iodide) have a salty taste (Pyke).

 

Less is known about sweet and bitter substances. There seems to be no relationship between [[organic chemistry|organic]] [[functional groups]] and sweet flavor (as almost every class of compound has a member which tastes sweet), yet at the same time the chemistry is very specific. For example, saccharine is 300 times sweeter than table [[sugar]] (sucrose), however if the [[hydrogen]] bonded to the [[nitrogen]] is replaced with a [[methyl]] group, all flavor sensation disappears (Pyke). Likewise, bitter sensations are difficult to classify, though many [[plant]]-derived [[molecule]]s which interact with the brain such as [[caffeine]] and [[nicotine]] (Reineccius), as well as large molecular weight ionic salts such as [[cesium]] chloride, [[rubidium]] bromide and potassium iodide (Pyke) produce bitter tastes.

''Umami'' (Japanese for “delicious”, “savory” or “meaty”) is a newcomer to the basic flavor group. ''Umami'' is associated with L-glutamate and is found in meat broths, sea weed broth and aged cheese. It can also be used in solid form, usually monosodium glutamate, MSG (Reineccius, Pyke). Unlike the other four flavors, ''umami'' is not thought to have a flavor of its own, but rather it intensifies other flavors already present, hence the common use of MSG in many prepackaged food items.

''Umami'' (Japanese for “delicious”, “savory” or “meaty”) is a newcomer to the basic flavor group. ''Umami'' is associated with L-glutamate and is found in meat broths, sea weed broth and aged cheese. It can also be used in solid form, usually monosodium glutamate, MSG (Reineccius, Pyke). Unlike the other four flavors, ''umami'' is not thought to have a flavor of its own, but rather it intensifies other flavors already present, hence the common use of MSG in many prepackaged food items.