He said that pullulan, a major ingredient of the Listerine breath strips, is tasteless and dissolves within seconds in the mouth. Methocel is added in small amounts to increase the tensile strength of the pullulan films.
The development of the taste strips solves a problem for researchers. According to Smutzer, no standardized method for rapidly measuring taste function in humans is currently available, and taste norms for the human population as a function of age and sex have yet to be determined.
"What is typically done in the lab is a 'sip and spit' test, where a liquid solution is prepared that contains dissolved tastant," Smutzer explained. "You then place a small amount of the solution, maybe half an ounce, into a small cup for the test subject to place into their mouth, swish around and then spit it out."
But this type of test is difficult to administer outside the lab because the solutions have a very short shelf life and are not very portable, he said. Another big problem with the liquid test is that it cannot be effectively used to examine selected regions of the tongue, such as just one side, the front or the back of the tongue.
"It is very difficult to do regional testing with the liquid test because it is tough to concentrate liquid in just one area of the mouth," said Smutzer, who is hoping to commercialize the taste strips. "We can alter the size or thickness of these strips, place them on a desired area of the tongue and allow saliva to dissolve them without causing the tastant to spread over the surface of the tongue."
Since different parts of the tongue may respond to different tastes, or may respond more or less strongly to the same taste stimulus. Smutzer said his taste strips could be used to develop detailed taste maps of the tongue surface, a project he plans to examine in t
|Contact: Preston M. Moretz|