Sour, Bitter, and Metallic Taste
Posted: May 7, 2009
If you know the cause of these unfavorable tastes, then you are one step closer to fixing the problem. The reason that taste disorders are related to bad breath is due to the sulfur produced by anaerobic bacteria, particularly on the back (dorsum) of the tongue. Although it was extremely difficult for us to find a direct relationship between sulfide molecules and this area of the tongue in American medical or dental textbooks, several Asian medical texts made reference to sour, bitter, and metallic tastes associated with the rear of the tongue. This is very logical because the bacteria that produce the sulfur compounds breed on the back of the tongue, which is the area that is susceptible to sour, bitter, and metallic tastes.
Neurologically, the sense of smell and the sense of taste have two distinct physical centers in the brain, where specific electrical impulses are received. However, they happen to be next door neighbors. Physical evidence shows that the receptors for the impulses are separate senses that often intermingle with each other. This causes some to detect a sense of odor, even though there is none, based on a stimulation in the taste center and vice versa.
Pharmaceutical companies realized early on that it could be very easy to fool the public by creating strong flavors in oral rinses, which would then be sensed by the brain as if the user's breath was fresh.
One must understand that just as seeing and hearing are two different senses, and so are smelling and taste. You can have a great mint taste in your mouth (after using Altoids, for example), but the odor being sensed by the person next to you at work can be a disagreeable sulfur odor. This is true because the sugar in those products stimulate the bacteria to produce more sulfur compounds.
Some oral rinses are flavored to taste like medicine with the distinct purpose of creating the sense to the user that product with that flavor is actually doing something.
pH and Tastes:
Bitter, metallic, and sour tastes are all acidic in nature. Our medicated products are the only ones of their type to be pH balanced in such a manner as to neutralize more oral acids. This is significant when attempting to raise the pH (make the environment less acidic) and eliminate these tastes in order to freshen the oral cavity. Instructions for products like TheraBreath's also include procedures in order to change the pH and methods to better attack the bacteria which are normally very difficult to reach.
For those individuals who may have a slightly more acidic oral environment/saliva, here's a helpful hint:
Sprinkle a small amount of baking soda on the bristles of your dry toothbrush. Then, place toothgel over the baking soda to cover the bristles - then brush. The baking soda neutralizes more of the oral acids and creates a cleaner taste sensation.