Taste perception

Taste-modality recognition is a function of the cells of the taste buds. Perception of the sensation is a result of complex processes in the brain. The biological events that are discussed are those that occur, or are suggested as occurring, in taste-receptor cells, beginning at the instant when the taste-stimulus molecule interacts with the cell, until the membrane of the receptor cell is polarized. These are peripheral events. However, our knowledge of the peripheral mechanisms in taste perception is not sufficiently complete to provide a detailed, biophysical explanation of this phenomenon. Nevertheless, several stages in this explanation have been hypothesized, and some are demonstrable. 

It has been proposed " that the mechanism(s) of action of gymnemic acids and ziziphins is a biphasic, model-membrane penetration-process. The model suggested that the modifier molecules interact first with the receptor-cell plasma-membrane surface. It was postulated that this initial interaction involves a selective effect on taste perception, including the transduction and quality specification of the sweet stimuli, and selective depression of sweetness perception. Following the initial interaction, the modifier molecules interact with the membrane-lipid interior to produce a general disruption of membrane function and a nonselective effect on taste... 

The dosage forms most commonly employed for pediatric formulations are liquids and chewable tablets. A perceived unpleasant taste is much more evident with these dosage forms than when a drug is administered as a conventional solid oral dosage form. Second, it is widely believed that children younger than the age of 6 years have more acute taste perception than older children and adults. Taste buds and olfactory receptors are fully developed in early infancy. Loss of taste perception accompanies the aging process. 

Taste analysis of water, 26 36 Taste buds, 77 565 Taste perceptions, 77 510-511 Taste receptors, discovery of, 24 248 Taste sensitivity, magnitude of, 77 566 Taste specification... 

Adverse reactions include alteration of taste perception in a high proportion of patients, drug fever, proteinuria and immune complex nephritis and an increased incidence of autoimmune diseases. Most feared are blood dyscrasias for which blood tests should be done regularly. 

May cause altered taste percept ion or cough persistent dry cough usually does not subside unless medication is stopped notify clinician if these symptoms persist... 

In biting their food and by means of a relatively small number of gustatory receptor cells, the larvae are informed about the composition of nutrients and secondary plant substances. Taste perception, the integration of sensory information in the insect s central nervous system, is not merely a process of summation. Synergistic as well as antagonistic effects between individual compounds can be observed in the food uptake of larvae on artificial diets. 

Different insect species posses different gustatory receptor cells, their response spectra being adapted to the perception of chemical components distributed in their host plant species (9 ). Taste perception in P. brassicae larvae forms a representative example for phytophagous insects, which are able to discriminate a number of compounds like sugars, amino acids, salts, and secondary plant substances acting as feeding inhibitors or feeding incitants (3,6,, 10). 

According to the theory of Zoeteman, the taste perception of water is a very good method of local control. We had taste tests carried out in Rotterdam, the Hague, and other big cities by the so-called consumer panels—not trained people, just consumers—and we let them rate the taste of the water. Well, we worked it out statistically and showed that the method was excellent. Now we polish the water treatment methods on the basis of taste perception. It is not expensive. It works quite well. 

Steiner JE, Rosenthal-Zifroni A, Edelstein EL. Taste perception in depressive illness. Isr Ann Psychiatr Relat Discip 1969 7(2) 223-32. 

The application of this concept to liquid samples is what we already refer to electronic tongue . It entails the use of multidimensional information coming from an array of chemical sensors, mimicking the animal sense of taste. As several possibilities exist on the side of which sensors form the array, the general response shown by the different sensors used is of paramount importance that is, cross-selectivity features are needed in order to profit from the multidimensional aspects of the information [7]. The performance of electronic tongues can be suited not only to qualitative purposes like identification of species and classification of sample varieties, but also to quantitative uses, normally the multidetermination of a set of chemical species, an interesting objective for process control. A more bioinspired trend is the artificial taste [8] in order to perform automated taste perception, especially in the industrial field. 

Concerning bread, characteristics such as cell wall thickness, cell size, and uniformity of cell size affect the texture of bread crumb (Kamman, 1970) and also the appearance, taste perception, and stability of the final product (Autio and Laurikainen, 1997). Crumb elasticity can be predicted from its specific volume and is strongly affected by the amylose-rich regions joining partially gelatinized starch granules in the crumb cell walls (Scanlon and Liu, 2003). 

Heimbeck G., Bugnon V., Gendre N., Haberlin C. and Stocker R. F. (1999) Smell and taste perception in Drosophila melanogaster larva toxin expression studies in chemosensory neurons. J. Neurosci. 19, 6599-6609. 

Differences in taste perception between individuals seem to be common. Peryam... 

Salty tastants act directly on Na+ channels in the PM of cells on the tongue surface. Direct passage of Na+ through these channels causes depolarization and thence signalling to the CNS. Much (but not all) salt taste perception is inhibited by the voltage-sensitive Na+ channel inhibitor amiloride (see Chapter 4) and evidently some salt perception also occurs via amiloride-insensitive channels. 

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