Changes

==The Five Flavors==

==The Five Flavors==

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).

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).

[[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.

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 “[[meat]]y”) 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.

Little is known about the mechanisms involved in tasting foods, but it is thought that sour and salty tastes utilize channels which allow inward proton transfer combined with H+-gated channels, while sweet, bitter and ''umami'' flavors utilize surface binding pathways to transmit flavor information. All five flavors depolarize the taste cell (which initially has a net negative internal charge) by causing the transfer of Ca2+ into the cell. This forms an electrical signal which is then sent to the brain and interpreted as flavor. When ''umami'' binds to a flavor cell, not only is there an influx of Ca2+ into the cell, but the cell also become more sensitive to the effects of other flavor compounds (Reineccius).

Flavor Production in Nature

 

 

==Flavor Production in Nature==

Historically, most science in the field of flavor has been dedicated to determining what flavor is rather than how it is produced. In addition, the metabolic pathways involved in flavor production are often very complicated, which their determination difficult. Recently, however, due to the demand for man-made flavors (especially the production of flavors able to be labeled “natural flavors”) more research has been focused in this area of study.

Historically, most science in the field of flavor has been dedicated to determining what flavor is rather than how it is produced. In addition, the metabolic pathways involved in flavor production are often very complicated, which their determination difficult. Recently, however, due to the demand for man-made flavors (especially the production of flavors able to be labeled “natural flavors”) more research has been focused in this area of study.

Unlike fruits, vegetables to not develop flavor over a long period of time, but rather through rapid enzymatic reactions after cellular disruption. Similar to fruit, fatty acids, amino acids, carbohydrates and proteins are the substrates for the flavor reactions, however sulfur-containing volatiles are much more important.

Unlike fruits, vegetables to not develop flavor over a long period of time, but rather through rapid enzymatic reactions after cellular disruption. Similar to fruit, fatty acids, amino acids, carbohydrates and proteins are the substrates for the flavor reactions, however sulfur-containing volatiles are much more important.

Flavor Production in Industry

==Flavor Production in Industry==

Flavors are manufactured and extracted for use in food and beverage by hundreds of different companies. They are primarily used in prepackaged food items, but they can also be sold to home consumers (in products such as imitation vanilla). Due to the difficulty (and sometimes impossibility) of patenting flavor compounds, many details of flavor manufacture are closely guarded secrets, however some general principles are known (Reineccius).

Flavors are manufactured and extracted for use in food and beverage by hundreds of different companies. They are primarily used in prepackaged food items, but they can also be sold to home consumers (in products such as imitation vanilla). Due to the difficulty (and sometimes impossibility) of patenting flavor compounds, many details of flavor manufacture are closely guarded secrets, however some general principles are known (Reineccius).

Since natural vanilla is very expensive, imitation vanilla is often used to mix with or completely replace natural vanilla. Imitation vanilla was produced from eugenol, which was itself produced by oil of clove, but now it is made from sulfite waste liquors from the paper industry (Reineccius).

Since natural vanilla is very expensive, imitation vanilla is often used to mix with or completely replace natural vanilla. Imitation vanilla was produced from eugenol, which was itself produced by oil of clove, but now it is made from sulfite waste liquors from the paper industry (Reineccius).

References

==References==

 

<references />

Greater Cincinnati Chamber of Commerce (GCCC), “Cincinnati USA: Chemistry Industry Leadership.” 2006. < http://www.gccc.com/pdf/ind_profile/ChemEng.pdf> Accessed November 11, 2007.

Leffingwell & Associates, “2002 - 2006 Flavor & Fragrance Industry Leaders.” 2007. <http://www.leffingwell.com/top_10.htm> Accessed November 11, 2007.

Leffingwell & Associates, “2002 - 2006 Flavor & Fragrance Industry Leaders.” 2007. <http://www.leffingwell.com/top_10.htm> Accessed November 11, 2007.

Reineccuis, Gary. Flavor Chemistry and Technology. Taylor & Francis: 2006.

Reineccuis, Gary. Flavor Chemistry and Technology. Taylor & Francis: 2006.

Vallod, D. et al. “Analysis of the off-flavor risk in carp production in ponds in Dombes and Forenz (France),” Aquaculture International. 15.3-4 (June 2007).

[[Category:Food and Drink]]