Taste, acid salty

Table 2 Hsts examples of compounds with taste and their associated sensory quaUties. Sour taste is primarily produced by the presence of hydrogen ion slightly modified by the types of anions present in the solution, eg, acetic acid is more sour than citric acid at the same pH or molar concentration (43). Saltiness is due to the salts of alkaU metals, the most common of which is sodium chloride. However, salts such as cesium chloride and potassium iodide are bitter potassium bromide has a mixed taste, ie, salty and bitter (44). Thus saltiness, like sourness, is modified by the presence of different anions but is a direct result of a small number of cations.

Moskowitz and Arabic (1970) found that the taste intensity (sweetness, sourness, saltiness, and bitterness) was related to the apparent viscosity of carboxymethylcel-lulose solutions by a power function with a negative slope. Pangbom et al. (1973) observed that the influence of different hydrocolloids on the perception of some basic taste intensities (saltiness, bitterness, sourness) appeared to be more dependent on the nature of the hydrocolloid and the taste of the substance than on the viscosity level. In contrast, sweetness imparted by sucrose was found to be highly dependent on viscosity, that is, the hydrocolloid concentration above a certain viscosity threshold, it was shown that the sweetness intensity of sucrose was significantly depressed. Saltiness was the taste attribute less affected, sourness, imparted by citric acid, was significantly reduced by all hydrocolloids tested, and for the other taste substances, the presence of a hydrocolloid generally enhanced the taste intensity of saccharin and depressed that of sucrose and caffeine (bitterness). 

From glutamic acid, MSG of more than 99 % purity is obtained by neutralization and purification. It consists of odourless white crystals. In aqueous solution, MSG tastes sweet-salty with a detection threshold of 0.01-0.03 % or 100-300 ppm [2, 10]. 

Insoluble substances have no taste. Sour taste is caused by the acids. Salty tastes are caused by ionizable salts. Cations of the salts are mainly responsible. Most of the... 

PMTh-, PANI-, aud PPy-modified electrodes includiug different anions Standard solutions Discrimination between soluticms containing chemical species representative of different tastes sweet, bitter, acid, salty, and astringcmt PCA [130]... 

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. 

A persistent idea is that there is a very small number of flavor quaUties or characteristics, called primaries, each detected by a different kind of receptor site in the sensory organ. It is thought that each of these primary sites can be excited independently but that some chemicals can react with more than one site producing the perception of several flavor quaUties simultaneously (12). Sweet, sour, salty, bitter, and umami quaUties are generally accepted as five of the primaries for taste sucrose, hydrochloric acid, sodium chloride, quinine, and glutamate, respectively, are compounds that have these primary tastes. Sucrose is only sweet, quinine is only bitter, etc saccharin, however, is slightly bitter as well as sweet and its Stevens law exponent is 0.8, between that for purely sweet (1.5) and purely bitter (0.6) compounds (34). There is evidence that all compounds with the same primary taste characteristic have the same psychophysical exponent even though they may have different threshold values (24). The flavor of a complex food can be described as a combination of a smaller number of flavor primaries, each with an associated intensity. A flavor may be described as a vector in which the primaries make up the coordinates of the flavor space. 

Organic aromatic molecules are usually sweet, bitter, a combination of these, or tasteless, probably owing to lack of water solubiUty. Most characteristic taste substances, especially salty and sweet, are nonvolatile compounds. Many different types of molecules produce the bitter taste, eg, divalent cations, alkaloids, some amino acids, and denatoirium (14,15). 

In Foods. Each amino acid has its characteristic taste of sweetness, sourness, saltiness, bitterness, or "umami" as shown in Table 13. Umami taste, which is typically represented by L-glutamic acid salt (and some 5 -nucleotide salts), makes food more palatable and is recognized as a basic taste, independent of the four other classical basic tastes of sweet, sour, salty, and bitter (221). 

Salzgeist, m. (Old Chem.) spirit of salt (hydrochloric acid). — leichter—, light spirit of salt (ethyl chloride). — schwerer —, ver-slisster —, heavy spirit of salt, sweet spirit of salt. — Libavius rauchender —, fuming liquor of Libavius (stannic chloride). Salz-gemisch, n. salt mixture, mixture of salts, -geschmack, m. salty taste,, -gestein, n. rock salt saliferous rock. 

Scharfxnanganerz, n. hausmannite. scharf-salzig, a. very salty, -sauer, a. strongly acid, very sour, -schmeckend, p.a. of a sharp taste, acrid, pungent, tart, -schweflig, a. strongly sulfurous. 

In fish, both taste and olfactory stimuli are waterborne. However, taste involves the seventh, ninth or tenth cranial nerves, in contrast to the first cranial nerve for smell. Elasmobranchs have their taste buds in the mouth and pharynx, but in bony fish they occur around the gills, on barbels and pectoral fins, and also scattered over the rest of the body surface. They crowd particularly in the roof of the mouth, forming the palatal organ. The taste receptor cells are arranged as a bundle to form a taste bud. Like other vertebrates, fish have receptors for sweet, sour, salty, and bitter. For instance, goldfish reject quinine-treated food pellets (Jobling, 1995). Many fish species are particularly sensitive to acidic taste characteristics. The responses of fish to amino acids will be discussed in Chapter 12. 

Unpleasant taste. Salty or brackish taste is caused by high sodium content. Metallic taste is caused by acidic water (pH 3.0-5.5), and heavy concentration of iron, lead, and copper. 

Sour and salty. Within the membrane of the taste cell are ion channels which control the movement of ions, such as sodium, potassium and calcium, into and out of the cell. Sour taste sensations are in part due to the effect of hydrogen ions however, some taste is also a function of the hydrophobicity of the organic acid, such as citric acid (18). Acids can produce a decrease in potassium ion conductance (depolarization) in the membrane. 

Expansion or enhancement of the proposed mechanism of Nakamura and Okai is shown in Figure 12. Their model is based on the demonstration that several synthetically prepared di- and tri- peptide fragments composed of basic or acidic amino acids, produced individual tastes such as salty (lys-gfy sweet (lys-gfy-asp), sour (asp-glu-glu) and bitter (ser-leu-ala 31). Tlie expanded mechanism we propose is shown in Figure 12 and is based on the data tabulated in Table 1 (31, 38). 

Taste of Dipeptides Containing Lys and/or Gly. Since Lys-Gly HCl produces the saltiness, we prepared some dipeptides composed of Lys and/or Gly. The results are listed in Table XI. Gly-Lys, of which the amino acid sequence is opposite to the salty peptide Lys-Gly-HCl, produced a weakly sweet taste instead of the salty taste. Dipeptide composed of only Lys or Gly did not any taste. 

Re-formation of the Taste of BMP. According to the above results, the taste of BMP might produced by the combination of the basic amino acid (Lys) at N-terminal and acidic amino acids at the middle part. To confrnn this idea, we prepared a mixed solution of the N-terminal dipeptide (Lys-Gly), the acidic tripeptide at the middle part (Asp-Glu-Glu) and C-terminal tripeptide (Ser-Leu-Ala) and examined the taste. We also studied tastes of a mixture in which a basic dipeptide fragment was replaced by Orn-p-Ala, a salty dipeptide, and a mixture in which Glu-Glu replaced an acidic tripeptide fragment. The result are shown in Table XIV. All of the combinations produced the same character of the taste as BMP. It means that the taste of BMP is mainly produced by the combined effect of the N-terminus basic dipeptide and the acidic tripeptide of the middle part. However, taste strength of the mixture became... 

Basic amino acid containing 0-aminoacyl sugars, saltiness, 165-167 Basic amino acid peptides, taste,... 

Reduction of the sodium chloride level can result in taste problems and flavour shifts. There are several approaches to maintain salt taste. Most often, potassium chloride is used, because it shows the most prominent salty taste of those applicable inorganic salts. Lithium chloride is the most salty salt but cannot be used for toxicological reasons. Most consumers, however, complain about the bitter, chalky taste of KCl-containing formulations. Development of sodium-reduced products using mineral salts is a challenge and the whole product formula has often to be adapted [25]. Therefore, the main focus of the research was the search for masking compounds or technologies to cover the bad taste of KCl, e.g. phenolic acids and derivatives [26] and lactisol [27]. 

In some cases, yeast preparations which contain a high amount of nucleotides can be used to increase saltiness in combination with masking ofiF-notes of KCl [30]. Additionally, use of low amounts of fruit acids may reduce the bad taste of KCl-containing food preparations [31]. Usage of low amounts of sweeteners such as thaumatin [32] or neotame [33] was described to mask the ofiF-taste of KCl. 

Salty taste enhancing preparations or compounds besides KCl were described. For example, a mixture of certain amino acids based on L-lysine were used to increase the saltiness of a NaCl-reduced preparation [34] y-aminobutyric acid (4) was also used as a salty taste enhancer [35]. Some dipeptides such as N-l-ornithyl taurine hydrochloride or N-L-lysinyl taurine hydrochloride were described as very salty with a clean salt taste [36]. Additionally, choline chloride was suggested as a salt enhancer [37]. 

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