Sweeteners structure

Sorbitol is a sweetener often substituted for cane sugar because it is better tolerated by dia betics It IS also an intermediate in the commercial synthesis of vitamin C Sorbitol is prepared by high pressure hydrogenation of glucose over a nickel catalyst What is the structure (including stereochemistry) of sorbitoP... 

Saccharin was discovered at Johns Hopkins Uni versity in 1879 in the course of research on coal tar derivatives and is the oldest artificial sweetener In spite of Its name which comes from the Latin word for sugar saccharin bears no structural relationship to any sugar Nor is saccharin itself very soluble in wa ter The proton bonded to nitrogen however is fairly acidic and saccharin is normally marketed as its water soluble sodium or calcium salt Its earliest applications were not in weight control but as a... 

Sucralose has the structure most similar to su crose Galactose replaces the glucose unit of sucrose and chlorines replace three of the hydroxyl groups Sucralose is the newest artificial sweetener having been approved by the U S Food and Drug Adminis tration in 1998 The three chlorine substituents do not dimmish sweetness but do interfere with the ability of the body to metabolize sucralose It there fore has no food value and IS noncaloric... 

For more information including theories of structure-taste relationships see the symposium Sweeteners and Sweetness Theory m the August 99S ssue oi the Journal of Chemical Education pp 671-683... 

Fig. 3. Structure—activity summary of dipeptide sweeteners, where n may be 0 or 1 (62). There are no known replacements for the acid or amide groups denoted by arrows, although thioamide has some sweetness. If the NH2 is replaced by NHC(0)R, the potency is increased when...

For more information, including theories of structure-taste relationships, see the symposium "Sweeteners and Sweetness Theory" in the August, 1995 issue of the Journal of Chemical Education, pp. 671-683. 

The sensation of sweetness obviously involves interaction between the sweetener and some sort of biological receptor. It might be expected, therefore, that sweeteners share common structural features. Is this the case ... 

Examine the structures oisucrose, the natural sweetener, and saccharin, sodium cyclamate and aspartame (Nutrasweet), three of the most common artificial sweeteners. What, if any, structural features do these molecules have in common Compare electrostatic potential maps for the different sweeteners. Are there any significant features in common Based on yom findings, do you think it is likely that entirely different artifical sweeteners might be discovered Explain. 

One similarity which sweeteners need to possess is water solubility. Point out structural features in both natural and artificial sweeteners which are likely to make them soluble. 

Sugars are used as sweeteners, as thickeners, and as structural elements in foods (e.g., to make granola cruchy and hard candies hard). 

Sweeteners such as sugar and corn syrup are added for taste, but they also participate in the structure of the foam and in the weight of the final product. 

Fig. 22.—Structure-Sweetness Relationship (With Regard to B-Ring Substitution) in Dihy-drochalcone Sweeteners.

Did you know the average American consumes the equivalent of 20 teaspoons of sugar each day The non-nutritive sweetener industry is described as a billion-dollar industry with projections of even more rapid expansion in the next few years. What do chemists look for in their search for an ideal sweetener Consumers seek good-tasting, nontoxic, low-caloric sweeteners. Chemists in the sweetener industry add further demands an inexpensive, easy-to-synthesize product that is readily soluble in water and resists degradation by heat and light is of prime importance. The chemical structure of sucralose keeps the sweetener intact as it passes through the acidic environment of the stomach. Thus, sucralose is not... 

NMR, protein structure determination, 23, 275 non-enzymatic glycosylation, 14, 261 non-HIV antiviral agents, 36, 119, 38, 213 non-nutritive, sweeteners, V7, 323 non-peptide agonists, 32, 277 non-peptidic d-opinoid agonists, 37,159... 

High intensity induced-roll magnetic separators, 15 453—454 High intensity sweeteners, 12 38, 41—43 High internal-efficiency structures, 14 844-845... 

The available intense sweeteners belong to very different structural classes of sweeteners (Table 10.1). They were normally discovered by chance. All internationally important sweeteners are produced synthetically and only two less important products are isolated from plants. 

Phenylalanine (Phe or F) (2-amino-3-phenyl-propanoic acid) is a neutral, aromatic amino acid with the formula HOOCCH(NH2)CH2C6H5. It is classified as nonpolar because of the hydrophobic nature of the benzyl side chain. Tyr and Phe play a significant role not only in protein structure but also as important precursors for thyroid and adrenocortical hormones as well as in the synthesis of neurotransmitters such as dopamine and noradrenaline. The genetic disorder phenylketonuria (PKU) is the inability to metabolize Phe. This is caused by a deficiency of phenylalanine hydroxylase with the result that there is an accumulation of Phe in body fluids. Individuals with this disorder are known as phenylketonurics and must abstain from consumption of Phe. A nonfood source of Phe is the artificial sweetener aspartame (L-aspartyl-L-phenylalanine methyl ester), which is metabolized by the body into several by-products including Phe. The side chain of Phe is immune from side reactions, but during catalytic hydrogenations the aromatic ring can be saturated and converted into a hexahydrophenylalanine residue. ... 

When type X is utQized, in any of its ion exchange forms, for dehydration or possibly for sweetening (sulfur removal), there is little likelihood that the intracrystalline diffusion will be the dominant resistance to mass transfer. Large aromatic sulfurs would of course be an exception. When type X is used for adsorption of hydrocarbons or aromatics then it is possible that the micro-pore diffusion might dominate. When type A is used there is always a distinct possibility that intra-crystalline diffusion will be slow and may dominate the mass transfer, even for relatively small molecules. This is especially true when the chosen structure is a K A or type 3A. Selection of other small pore structures, for separations or purification applications can also create situations where the dominant resistance is found in the crystaUites. 

Instantisation, in which the fluidized bed is responsible for a significant change to the structure and size of the granules, should not be confused with the use of an integrated fluidized bed drier immediately following spray drying. There are many descriptions in the literature of such processes a recent example of a novel application of this technique (Jha et al, 2002) is in the production of a shelf-stable powdered kheer mix, an Indian dessert which consists of a sweetened mixture of cooked partially concentrated milk and rice flour. This is spray dried, the particles are then dried in a fluidized bed and finally dry blended with sugar. 

The spiroacetal morpholine work of Scheme 38 subsequently inspired research on the preparation of a novel family of morpholino-glycosides from sucrose via lead tetraacetate cleavage and reductive amination (Scheme 40). Significantly, the latter work, which was done with the present author, unveiled a completely new structural class of sweeteners, more intense than sucrose but having a similar taste profile. 

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