Taste, sweet

CioHi O. White leaflets, with a strong smell and sweet taste, m.p. 22 C, b.p. 235 C. The chief constituent of anise and fennel oils and other essential oils, from which it is manufactured. It can also be prepared from anisole (meihoxybenzene). It is widely used for flavouring pharmaceuticals and dentifrices, and in perfumery. 

HOCHj CHjOH. Colourless, odourless, rather viscous hygroscopic liquid having a sweet taste, b.p. 197 C. Manufactured from ethylene chlorohydrin and NaHC03 solution, or by the hydration of ethylene oxide with dilute sulphuric acid or water under pressure at 195°C. Used in anti-freezes and coolants for engines (50 %) and in manufacture of polyester fibres (e.g. Terylene) and in the manufacture of various esters used as plasticizers. U.S. production 1979 1 900 000 tonnes. 

CH3 CH0H CH20H, a colourless, almost odourless liquid. It has a sweet taste, but is more acrid than ethylene glycol b.p. 187. Manufactured by heating propylene chlorohydrin with a solution of NaHCO under pressure. It closely resembles dihydroxyethane in its properties, but is less toxic. Forms mono-and di-esters and ethers. Used as an anti-freeze and in the preparation of perfumes and flavouring extracts, as a solvent and in... 

CH20H-CH(0H)-CH,0H, C3HHO3. Normally obtained as a colourless, odourless, viscous liquid with a very sweet taste. M.p. 20 C, b.p. 182 C/20mm. It absorbs up to 50% of its weight of water vapour. It occurs (glycerides) in combination with various fatly acids in all animal and vegetable fats and oils. 

All colourless solids, which decompose on heating and therefore have no definite m.p.s. All insoluble in ether (like most polyhydroxy-compounds). All except starch are soluble in water and have a sweet taste. Starch as ordinarily supplied is insoluble in... 

Students arc strongly advised not to attempt identification of the soluble carbohydrates by taste—quite apart from the fact that other compounds (c.g., saccharin] also have a sweet taste, the tasting of an imperfectly identified organic compound u too dangerous an operation. 

Fig. 1. Sweet-tasting compounds of various chemical classes and their common (ah-b) unit, (a) P-D-fmctose (b) saccharin (c) chloroform (d) unsaturated...

Lactulose. 4-O-P -D-Galactopyranosyl-4-D-fmctofuranose [4618-18-2] (Chronolac) (12) may be made from lactose using the method described in Reference 9. It is a synthetic disaccharide that is not hydroly2ed by gastrointestinal enzymes in the small intestine, but is metabolized by colonic bacteria to short-chain organic acids. The increased osmotic pressure of these nonabsorbable organic acids results in an accumulation of fluid in the colon. Lactulose may not be tolerated by patients because of an extremely sweet taste. It frequently produces flatulence and intestinal cramps. 

The sweet taste of sucrose is its most notable and important physical property and is regarded as the standard against which other sweeteners (qv) are rated. Sweetness is induenced by temperature, pH, sugar concentration, physical properties of the food system, and other factors (18—20). The sweetening powers of sucrose and other sweeteners are compared in Table 3. The sweetness threshold for dissolved sucrose is 0.2-0.5% and its sweetness intensity is highest at 32-38°C (19). 

In general, these polyols are water-soluble, crystalline compounds with small optical rotations in water and a slightly sweet to very sweet taste. Selected physical properties of many of the sugar alcohols are Hsted in Table 1. 

Alitame (trade name Adame) is a water-soluble, crystalline powder of high sweetness potency (2000X, 10% sucrose solution sweetness equivalence). The sweet taste is clean, and the time—intensity profile is similar to that of aspartame. Because it is a stericaHy hindered amide rather than an ester, ahtame is expected to be more stable than aspartame. At pH 2 to 4, the half-life of aUtame in solution is reported to be twice that of aspartame. The main decomposition pathways (Fig. 6) include conversion to the unsweet P-aspartic isomer (17) and hydrolysis to aspartic acid and alanine amide (96). No cyclization to diketopiperazine or hydrolysis of the alanine amide bond has been reported. AUtame-sweetened beverages, particularly colas, that have a pH below 4.0 can develop an off-flavor which can be avoided or minimized by the addition of edetic acid (EDTA) [60-00-4] (97). 

An alternative view (123) is that no single model can adequately explain why any given compound is sweet. This hypothesis derives from several features. First, there is the observation that all carbohydrates having a critical ratio of OH to C are sweet tasting. In other words, there are no stmctural constraints to the sweetness of carbohydrates. Second, not all sweeteners can be fit to the same SAR model. Rather, some fit one, others fit another. Third, studies on the transduction mechanisms of sweetness suggest more than a single mechanism for sweet taste, implying multiple receptors for sweeteners. 

Inhibitors. Sugar is used in large quantities in fmit jams as a preservative. The strong sweetness, however, prevents fmity flavors from being noticed. For these and other foods that must use a large amount of sugar for purposes other than sweet taste, there is need for a sweet-taste inhibitor. 

Lactisole [13794-15-5] the sodium salt of racemic 2(4-methoxyphenoxy)propionic acid, is a sweet-taste inhibitor marketed by Domino Sugar. It was affirmed as a GRAS flavor (FEMA no. 3773). At a concentration of 100 to 150 ppm, lactisole strongly reduces or eliminates the sweet taste of a 10% sugar solution. This inhibition appears to be receptor-related because lactisole also inhibits the sweet taste of aspartame. The 5 -( —)-enantiomer [4276-74-8] (38), isolated from roasted coffee beans, is the active isomer the i -(+)-enantiomer is inert (127). 

M. Mathlouthi, J. A. Kanters, and G. G. Birch, Sweet-Taste Chemoreception Elsevier Science Publishing Co., Inc., New York, 1993. 

Whenever a hydrocarbon backbone has two hydroxyl radicals attached to it, it becomes a special type of alcohol known as a glycol. The simplest of the glycols, and the most important, is ethylene glycol, whose molecular formula C2H4(OH)2. The molecular formula can also be written CHjOHCHjOH and may be printed as such on some labels. Ethylene glycol is a colorless, thick liquid with a sweet taste, is toxic by ingestion and by inhalation, and among its many uses is a permanent antifreeze and coolant for automobiles. It is a combustible liquid with a flash point of 240"F. 

The last group of substituted hydrocarbons produced by adding hydroxyl radicals to the hydrocarbon backbone are the compounds made when three hydroxyl radicals are substituted these are known as glycerols. The name of the simplest of this type of compound is just glycerol. Its molecular formula is 3115(011)3. Glycerol is a colorless, thick, syrupy liquid with a sweet taste, and has a flash point of 320°F, and is used to make such diverse products as candy and explosives, plus many more. Other glycerols are made, but most of them are not classified as hazardous materials. 

Properties.—A viscid, colourless liquid, with a sweet taste m.p. 17°, b. p. 290°. It boils, under ordinary pressure. with partial decomposition forming acrolein sp gr. radp at 12° miscible with w ater and alcohol Insoluble in ether and the hydrocarbons. 

The amino-acids are crystalline compounds usually of a sweet taste and soluble in water They are ncutial compounds, from which It may be assumed that an inner ammonium salt is foimecl —... 

Some proteins display rather exotic functions that do not quite fit the previous classifications. Monellin, a protein found in an African plant, has a very sweet taste and is being considered as an artificial sweetener for human consumption. Resilin, a protein having exceptional elastic properties, is found in... 

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