Sucralose, structure sweetness

Substituent effect, additivity of, 570 electrophilic aromatic substitution and, 560-563 summary of. 569 Substitution reaction, 138 Substrate (enzyme), 1041 Succinic acid, structure of, 753 Sucralose, structure of. 1006 sweetness of, 1005 Sucrose, molecular model of. 999 specific rotation of, 296 structure of, 999 sweetness of, 1005 Sugar, complex, 974 d, 980 L, 980... 

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... 

Saccharin sucralose and aspartame illustrate the diversity of structural types that taste sweet and the vitality and continuing development of the in dustry of which they are a part ... 

Sweet Taste. The mechanism of sweetness perception has been extensively studied because of its commercial importance. Many substances that vary in chemical structure have been discovered which are similar to the taste of sucrose. Commercial sweeteners include sucralose, acesulfame-K, saccharin, aspartame, cyclamate (Canada) and the protein thaumatin 4), Each sweetener is unique in its perceived sensation because of the time to the onset of sweetness and to maximum sweetness, ability to mask other sensations, persistence, aftertaste and intensity relative to sucrose [TABLE IT. For example, the saccharides, sorbitol and... 

The disaccharide structure of (12) (trade name SPLENDA) is emphasized by the manufacturer as responsible for a taste quality and time—intensity profile closer to that of sucrose than any other high potency sweetener. The sweetness potency at the 10% sucrose solution sweetness equivalence is between 450 and 500X, or about two and one-half times that of aspartame. When compared to a 2% sugar solution, the potency of sucralose can be as high as 750X. A moderate degree of synergy between sucralose and other nonnutritive (91) or nutritive (92) sweeteners has been reported. 

Another widely used artificial sweetener is sucralose which is made by modifying sucrose (compare the structure of sucralose to sucrose shown above). Look at the groups with blue circles in each structure. Sucralose is 600 times as sweet as sucrose and is used to sweeten beverages, baked goods, yogurt, and desserts. 

Acesulfame potassium, one of the most recently approved sweeteners, is proving to be extremely popular in soft drinks because it has little aftertaste. Sucralose, another recently approved sweetener, is particularly useful in baked goods because of its stability at high temperatures. Alitame, marketed in some countries under the name Adame, is not approved for sale in the United States. It is some 2000 times as sweet as sucrose and, like acesufame-K, has no aftertaste. Of the five synthetic sweeteners listed in Table 21.2, only sucralose has clear structural resemblance to a carbohydrate, although it differs dramatically in containing three chlorine atoms. Aspartame and alitame are both dipeptides. 

The newest frontier in sweetener research is the area of sweet enhancers. These substances, while tasteless themselves, cause sweetness receptors to respond more strongly to sweet substances. For example, the simple experimental molecule dubbed SE-2 enhances the sweetness of sucralose up to eightfold. It is thought that SE-2 and related structures bind to the Venus flytrap complex at a remote site from the sweetener itself, causing the trap to stay shut for longer periods of time. Sucrose and sucralose enhancers are beginning to be commercialized around the... 

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