Sucrose substitutes sweetness

Table 23.2 gives the relative sweetness of the mono- and disaccharides considered here, along with sucrose substitutes. 

Fructose, prepared from hydrolysis of sucrose and isomerization of glucose is used in the manufacture of candy, soft drinks, and other processed foods. As fructose is 124 percent as sweet as sucrose, substitution of fructose for sucrose in foods permits a reduction in the calorie content of a food. 

The search for improved sucrose substitutes is continuing, and one of the most potent sweeteners synthesized so far is the N-cyclononylguanidine derivative, sucrononic acid. This is actually the sweetest compound reported in the literature to date with a sweetness... 

Besides the naturally occurring saccharides and polyols, there are a number of plant-derived highly sweet compounds, which are mostly terpenoids, flavonoids, and proteins [16-18]. Several of these sweet substances are used commercially as sucrose substitutes, as will be described in the next section. In addition, a number of plant substituents are known to mediate the sweet-taste response, either by inducing or inhibiting the perception of sweemess [19]. Thus far, all of the known natural product sweet-tasting substances and sweetness modifiers have been obtained from green plants [16-19]. In the remaining sections of this chapter, plant-derived sweet compounds with commercial use will be described, followed by a section on recent theories on the sweet taste phenomenon, and then individual descriptions of potent sweeteners, sweetness inducers, and sweetness inhibitors from plants will be presented in turn. The literature has been surveyed for this chapter until the end of 1999. 

The intensely sweet sesquiterpene, Hernandulcin, was isolated from a plant known to the Aztecs as Tzonpelic Xihuilt or sweet herb (Lippia dulcis). Hernandulcin which could be considered the prototype of a new class of dietary sucrose substitutes is said over 1000 times sweeter than sucrose. However to a human panel at SNPE, while tasting synthetic Hernandulcin made by the new methodology, some aftertaste and a slight bitterness was perceived by 50 % of the persons. 

Sweeteners, natural. Noncaloric sucrose substitutes for use in the sweetening of foods, beverages and medicines may be either synthetic compounds or natural products. Highly sweet, potentially noncariogenic sweeteners from plants are used in Japan and some... 

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. 

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... 

The relationship between structure and enhancement of sweetness in chlorodeoxysucroses was studied by Hough and Khan. Examination of a range of mono-, di-, tri-, and tetra-chlorodeoxy derivatives of sucrose and galacto-sucTOse suggested that C-4, C-1, and C-6 appear to be important in the enhancement of sweetness when substituted with chloro substituents. The increase in sweetness is substantial if a combination of two of these hydroxyl groups is replaced for example, the 4,l -dichloride (55) and the r,6 -dichloride (56) were reported to be respectively 120 and 76 times... 

The binding specificity of d-[ C]glucose by the taste-papillae membranes, compared to that of control membranes isolated from epithelial tissue, has been confirmed in two studies. One inherent problem in the approach is that the stimuli, primarily carbohydrate sweeteners, are not ideal model compounds to use, as they are not active at low concentrations and do not show sufficiently high binding-constants. The use of other stimulus compounds that are at least several hundred times sweeter than sucrose, such as saccharin, dihydrochalcone sweeteners, dipeptide sweeteners, stevioside, perillartine and other sweet oximes, the 2-substituted 5-nitroanilines, and... 

A large number of sweet-tasting substances has been described in the scientific literature, most of them in the course of the last 20 to 30 years. The number of substances having an intense sweetness is by far higher than the number of products with a sweetening power similar to sucrose which could therefore be used as bulking sugar substitutes. Only a small number of these has found... 

Xylitol is as sweet as sucrose and has been used as a food additive. Because it does not induce formation of dental plaque, it is used as a replacement for sucrose in chewing gum. It appeared to be an ideal sugar substitute for diabetics. However, despite the fact that it is already naturally present in the body, ingestion of large amounts of xylitol causes bladder tumors as well as oxalate stones in rats and mice. Its use has, therefore, been largely discontinued. A possible source of the problem may lie in the conversion by fructokinase of some of the xylitol to D-xylulose 1 -P, which can be cleaved by the xylulose 1-P aldolase to dihydroxy acetone P and glycolaldehyde. 

Polyols are frequently used sugar substitutes and are particularly suited to situations where their different sensory and functional properties are attractive. In addition to sweetness, some of the polyols have other useful properties. For example, although it contains the same number of calories/gram as other sweeteners, sorbitol is absorbed more slowly from the digestive tract than is sucrose. It is, therefore, useful in making foods intended for special diets. When consumed in large quantities (1-2 oz 25,059 g)/dav, sorbitol can have a laxative effect, apparently because of its comparatively slow intestinal absorption. 

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