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Sensation bitter

After the saliva has carried the tastants into the taste bud, they interact with the taste receptors on the surface of the cells, or with ion channels, which are pore-like proteins. Salty and sour tastants act through ion channels, and sweet and bitter sensations are mediated by surface receptors. The different taste submodalities rely on specific mechanisms Na+ flux through Na+... [Pg.109]

Some spices such as clove and cinnamon can accomplish the desensitizing of taste buds by creating a mild pain reaction through the introduction of heat and numbness. Likewise various sweeteners may provide different sensations in the mouth. Saccharin may give a rapid bitter sensation followed by the sweet flavor... [Pg.175]

External Characters —Honey may be white (centrifuged honey) or brown (coniferous honey), or pale yellow, yellow, dark yellow, greenish yellow or reddish, and its taste should be more or less markedly sweet with an almost imperceptible bitter sensation (due to small proportions of malic... [Pg.159]

A complete different mechanism seems to be present in the bitterness of salts, as two bitter sensations are differentiated (90) bitter I as elicited by stimuli like 1-tryptophan, this would correspond to our "hydrophobic bitterness" and bitter II, elicited e.g. by MgSO. This bitter II seems to be triggered by ions. Kionka and Stratz (91) comparing 1 n solutions of the different alkali halo-genides made a separation in three groups as shown in Table XXIII salty, salty + bitter, bitter. [Pg.168]

Several review articles have described the chemistry of taste and structure-activity relationships.13,14 Two comprehensive reviews have been published in Japan (in Japanese), with particular focus on taste compounds.15,16 However, there has been no recent comprehensive review written from the perspective of natural products chemistry. In this chapter, several taste sensations found in natural products are described along with their structures. Unfortunately, however, it is still very difficult to anticipate the taste quality and intensity from the structure of an organic compound, even for the thoroughly studied sweet and bitter sensations, although some regularity has been observed. It is expected that recent progress in the study of receptors will contribute to a full understanding of the relationship between taste sensation and chemical structure. [Pg.633]

The microbiological breakdown of glycerol forms acrolein, a product which causes bitterness in wine by binding with phenolic components (Singleton 1995). Ethanol increases the intensity of the bitter taste, as well as the duration of the bitter sensation (Noble 1994). An increased alcohol concentration resulted in an increase in the bitter sensation (Eischer and Noble 1994). Lactobacillus brevis and L. buchneri, isolated from spoiled wine, can metabolize glycerol in the presence of... [Pg.45]

Apart from the five normal basic tastes - sweet, sour, salty, bitter and umami- a great many other actions occur in the mouth, although their importance here is limited. The basic taste sensations are experienced in different areas of the tongue. For example, sweetness is tasted more at the tip of the tongue, sour sensation move on the sides towards the back of the tongue and saltiness on both sides towards the front (Fig. 6.2). Bitter sensations are perceived predominantly towards the back of the tongue, although the precise location varies between individuals, in some cases almost as far back as the throat. This is why it is often difficult to ascertain bitterness. It is best to lick a small sample, so that if possible more papillae are reached. [Pg.578]

In contrast, when a sample of beer was swallowed the intensity of the bitterness continued to rise for a further 8 s before starting to fall (Fig. 23.6). The bitter sensation appears to persist longer (60-90 s) than the sweet sensation. [Pg.471]

Sensory perception is both quaUtative and quantitative. The taste of sucrose and the smell of linalool are two different kinds of sensory perceptions and each of these sensations can have different intensities. Sweet, bitter, salty, fmity, floral, etc, are different flavor quaUties produced by different chemical compounds the intensity of a particular sensory quaUty is deterrnined by the amount of the stimulus present. The saltiness of a sodium chloride solution becomes more intense if more of the salt is added, but its quaUty does not change. However, if hydrochloric acid is substituted for sodium chloride, the flavor quahty is sour not salty. For this reason, quaUty is substitutive, and quantity, intensity, or magnitude is additive (13). The sensory properties of food are generally compHcated, consisting of many different flavor quaUties at different intensities. The first task of sensory analysis is to identify the component quahties and then to determine their various intensities. [Pg.1]

Several aspects affect the extent and character of taste and smell. People differ considerably in sensitivity and appreciation of smell and taste, and there is lack of a common language to describe smell and taste experiences. A hereditary or genetic factor may cause a variation between individual reactions, eg, phenylthiourea causes a bitter taste sensation which may not be perceptible to certain people whose general abiUty to distinguish other tastes is not noticeably impaired (17). The variation of pH in saUva, which acts as a buffer and the charge carrier for the depolarization of the taste cell, may influence the perception of acidity differently in people (15,18). Enzymes in saUva can cause rapid chemical changes in basic food ingredients, such as proteins and carbohydrates, with variable effects on the individual. [Pg.10]

Simultaneous stimulation of the tongue with the appHcation of different taste stimuli produces an interaction, modification, or blending of the stimuli in some instances but not in others. Warm and cold sensations are reported to act similarly on the tongue in two groups bitter, warm, and sweet and sour, cold, and salty (24). The theory of the specificity of the taste buds may be subject to modification (25). [Pg.11]

A SAPP with intermediate reactivity is used in combination with fast-acting MCP for the manufacturer of industrial baking powder and for retail and wholesale prepared cake mixes. SAPP imparts a bitter aftertaste which is often characterized as a mild burning sensation, especially when used in a product of low sweetness. SAPP is normally used at an NV of 72. However, it may be used at slightly higher or lower NV to obtain specific effects in certain types of baked goods. [Pg.469]

Adverse reactions associated with use of the carbonic anyhydrase inhibitors include ocular burning, stinging, or discomfort immediately after administration, bitter taste, ocular allergic reaction, blurred vision, tearing, dryness, dermatitis, foreign body sensation, ocular discomfort, photophobia, and headache. [Pg.626]

A century ago, Fick proposed the concept of four primary tastes, namely, sweet, salty, sour, and bitter. It has since been found that taste sensations are not describable by a single collection of discrete primaries. Electrophysiological studies of afierent taste-units in the chorda tympani and glossophyrangeal nerves have revealed that a continuous spectrum of gustation may be based on these four taste elements. Furthermore, the intensities of the tastes that we commonly experience are due not only to gustatory sensations but also to tactile, hot and cold, and, above all, olfactory sensations. The complexities of taste studies are such that, unless one of the taste modalities is singled out for study, there is very little hope of success. [Pg.339]

There are five primary taste sensations salty, sour, sweet, bitter, and umami (or savory). The receptors for these tastes are encoded in a few dozen genes in the human genome. These are expressed in taste buds. [Pg.369]

Researchers have oscillated between emphasizing specificity of neurons ( labeled lines ) and responses to a spectrum of tastants by one cell. More recently, patterns of activation of a number of sensory cells are favored for coding specific taste sensations (Smith and Margolskee, 2001). Neural distinction of different tastes requires simultaneous activation of different cell types. The brain receives a single channel of information, simply bitter for a number of different compounds. [Pg.110]

Assessment of taste is achieved by sensory analysis, from very simple experiments such as triangular tests aiming at determining detection thresholds to complex descriptive analysis approaches. A method referred to as time-intensity that consists in recording continuously the intensity of a given sensation over time under standardized conditions has been applied to study flavonoid bitterness and astringency properties. [Pg.304]

Reviews of taste sensations normally concentrate on four basic tastes - sweet, salty, sour and bitter (7,2) however, other oral sensations can contribute important information to the perceived flavor (3), Examples of stimulants evoking these very different sensory sensations are shown in TABLE I. Studies on the mechaiusms of perception are usually restricted to sensation-specific stimuli however, food flavors represent an interaction among the various sensations. This chapter describes recent... [Pg.10]

The sweet taste and olfactory responses to a variety of stimuli are examples of chemical senses that utilize protein receptors for initial detection of the stimulus. Most bitter compounds have a hydrophobic component which enables their direct interaction with the cell membrane however, some evidence suggests a protein receptor mechanism. The cooling sensation is treated as a chemesthetic sense, where stimulation takes place at the basal membrane. However, compounds that evoke this response have very specific structural limitations, and most are related to menthol. For purposes of discussion, bitter and cooling sensations will be discussed under generalized receptor mechanisms. [Pg.11]


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See also in sourсe #XX -- [ Pg.14 , Pg.17 ]




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