Chemistry · Ch 16 — Chemistry in Everyday Life
Artificial Sweetening Agents
Artificial Sweetening Agents
Artificial Sweetening Agents: Sweetness Without the Calories
Natural sweeteners such as sucrose contribute directly to calorie intake, which has driven the development of artificial sweeteners - compounds that provide a sweet taste while adding little or no caloric value, and which are of particular value to diabetics and to calorie-conscious consumers generally.
Saccharin (chemically, ortho-sulphobenzimide), discovered in 1879, was the first artificial sweetener to achieve popular use. It is roughly 550 times as sweet as an equal mass of cane sugar, and, importantly, it is excreted from the body unchanged in urine, appearing to be chemically inert and harmless to the body's own metabolism.
Other artificial sweeteners subsequently developed and marketed are compared below, together with their sweetness relative to cane sugar:
| Artificial sweetener | Structural formula | Sweetness value in comparison to cane sugar |
|---|---|---|
| Aspartame | Methyl ester of a dipeptide, drawn as: HO-C(=O)-CH2-CH(NH2)-C(=O)-NH-CH(CH2-C6H5)-C(=O)-OCH3, with the left-hand portion bracketed and labelled 'Aspartic acid part' and the right-hand CH2-C6H5-bearing portion bracketed and labelled 'Phenylalanine methyl ester part'. | 100 |
| Saccharin | Ortho-sulphobenzimide: a benzene ring ortho-fused to a five-membered ring containing -C(=O)- (drawn as 'CO'), -NH-, and -SO2- (benzisothiazol-3(2H)-one 1,1-dioxide). | 550 |
| Sucralose | A detailed stereochemical (wedge/dash) structural diagram of trichlorosucrose: two fused six-membered sugar rings (a galactose-type and a fructose-type ring) joined through an oxygen bridge, drawn with three Cl substituents (labelled Cl, and CH2Cl on both rings) replacing three of sucrose's -OH groups, plus retained -OH, -CH2OH/-CH2OH and -H substituents in standard sugar stereochemical notation. | 600 |
| Alitame | A tripeptide-like chain drawn as: HO-C(=O)-CH2-CH(NH2)-C(=O)-NH-CH(CH3)-C(=O)-NH-CH<, where the final CH is part of a ring fused through a sulphur atom to a 2,2,4,4-tetramethyl-substituted ring (drawn as a five-membered ring bearing S and two -C(CH3)2- units, i.e. a 2,2,4,4-tetramethylthietanyl group). | 2000 |
| Artificial sweetener | Structural formula | Sweetness value in comparison to cane sugar |
|---|---|---|
| Aspartame | Methyl ester of a dipeptide, drawn as: HO-C(=O)-CH2-CH(NH2)-C(=O)-NH-CH(CH2-C6H5)-C(=O)-OCH3, with the left-hand portion bracketed and labelled 'Aspartic acid part' and the right-hand CH2-C6H5-bearing portion bracketed and labelled 'Phenylalanine methyl ester part'. | 100 |
| Saccharin | Ortho-sulphobenzimide: a benzene ring ortho-fused to a five-membered ring containing -C(=O)- (drawn as 'CO'), -NH-, and -SO2- (benzisothiazol-3(2H)-one 1,1-dioxide). | 550 |
| Sucralose | A detailed stereochemical (wedge/dash) structural diagram of trichlorosucrose: two fused six-membered sugar rings (a galactose-type and a fructose-type ring) joined through an oxygen bridge, drawn with three Cl substituents (labelled Cl, and CH2Cl on both rings) replacing three of sucrose's -OH groups, plus retained -OH, -CH2OH/-CH2OH and -H substituents in standard sugar stereochemical notation. | 600 |