|MadSci Network: General Biology|
Besides taste buds on the tongue, taste receptors are distributed on the epiglottis, the pharynx, the soft palate, the anterior faucial pillars, and a few on the cheeks and the undersurface of the tongue. Taste buds dilminish with age, first those on the middorsal region and then those on the tip of the tongue. Four tastes are recognized by people: salt, acid or sour, sweet, and bitter. There are considerable individual differences in taste sensitiveness. Certain people are "aguesia" or taste blind. In some cases, taste blindness is limited to a few substances. There may have been more recent tests on taste blindness, but in tests some years ago with phenylthiocarbamide, a very bitter tasting compound, it was tasteless for about 5% of the population. This type of taste blindness is a hereditary trait, transmitted by a simple mendelian recessive factor. At a meeting of scientists, the taste of an unknown substance (maltose) was tested. The answers obtained were sweet, bitter, acid, salt, insipid, complex-that is to say all of the possible answers. Thus, diversity in taste was remarkably demonstrated by this experiment. The use of pepper on foods may only indicate that certain people like a peppery flavor for an otherwise bland food. During the last 10 years Mexican foods, with hot-spicy flavors, have sold increasingly well. This is true even with people that had not tasted Mexican foods until their teens or early adult periods. This has nothing to do with taste blindness but has to do with an increased acceptance and then a desire for the spicy and hot pepper flavors of Mexican foods.
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