Sweeteners sweetness

The most commonly used sweeteners are sucrose, glucose, fructose, sorbitol, and glycerin. Using sucrose (sugar) as a standard, with 100 units of sweetness. Table 6 lists the relative intensities of other sweeteners. Sweetness intensity changes with concentration. It has been estimated that the sweetness of glucose relative to cane sugar is 53 at a concentration of 8% but... 

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. 

With this general background, some work has teen carried out on the effect of low concentrations of sucrose and, in some cases, dextrose on the flavor of cooked foods which are commonly seasoned with butter, salt, and pepper. In earlier studies of various sweeteners, sweet taste was a flavoring, since it was predominant in the flavor of the strawberry preserves (10), frozen peaches (5), red raspberries, blackberries U), and strawberries. In addition, it counteracted some of the inherent sourness and enhanced natural fruit character. The following studies were designed to test the potentialities of sweeteners as seasonings. 

A famous incident of unintentional ingestion was that of Constantine Falhberg who, in 1879, synthesized the saccharin molecule. Since lab safety procedures were less cautious at the time, he contaminated his hands with the powder, didn t wash his hands after leaving the lab, and later detected an unusually sweet and off taste when the saccharin was inadvertently transferred to his food. Since saccharin is about 300 times sweeter (per gram) than common table sugar, even a small amount was noticeable. In fact, the off taste is characteristic of saccharin in doses higher than the amounts now used, for example, in the sweetener Sweet and Low . 

Carbohydrate Sweetness Relative to Sucrose Artifidal Sweetener Sweetness Relative to Sucrose... 

Artificial sweeteners are a billion dollar per year industry The primary goal is of course to maxi mize sweetness and minimize calories We II look at the following three sweeteners to give us an over view of the field... 

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... 

Swaits reactions Sweat glands Sweep flocculation Sweet basil Sweet basil oil Sweet chocolate Sweet crude oil Sweeteners... 

Com as com flakes, sweet com, com as various types of flour and meal, popcorn, other snacks foods such as chips, and com juice as sweeteners, com used in fermentation for beer and in the production of alcohol, and corncobs and stalks used as carriers for various chemicals and medications, as fiber sources, and for the improvement of soil condition by plowing under stalks, are some of the uses for this versatile crop. See Ref. 75 for more information on corn. 

Fructose—Dextrose Separation. Emctose—dextrose separation is an example of the appHcation of adsorption to nonhydrocarbon systems. An aqueous solution of the isomeric monosaccharide sugars, C H 2Dg, fmctose and dextrose (glucose), accompanied by minor quantities of polysaccharides, is produced commercially under the designation of "high" fmctose com symp by the enzymatic conversion of cornstarch. Because fmctose has about double the sweetness index of dextrose, the separation of fmctose from this mixture and the recycling of dextrose for further enzymatic conversion to fmctose is of commercial interest (see Sugar Sweeteners). 

Texture also influences the evaluation of taste. Sweetness in a Hquid is associated with body or viscosity. An artificially sweetened beverage that lacks body, therefore, may be rated quaUtatively lower than one equally sweet but containing sucrose. 

Bulking sweeteners provide a bulking effect, along with some of the sweetness and functional properties of sugar. They may be used alone to replace sugar in appHcations that can tolerate some reduction in sweetness. Products that fall into this category include mannitol [69-65-8], a sugar alcohol... 

Saccharin. Sacchatin [81-07-2] C H NO S, which is approximately 300 times as sweet as sucrose ia coaceatratioas up to the equivaleat of a 10% sucrose solutioa, has beea used commercially as a nonnutritive sweeteaer siace before 1900, predomiaanfly ia carboaated soft drioks, tabletop sweeteaers, and dietetic foods marketed primarily to diabetics. In 1977, the FDA proposed a ban on sacchatin because of its association with bladder cancer ia laboratory animals. At the time, it was the only commercially available nonnutritive sweetener, and pubflc outcry led to a delay of the ban, which was officially withdrawn ia 1991. Instead, the FDA required that warning labels be placed on all foods that contained the iagredient. Although sacchatin is heat stable, the pubflc debate over its safety, as well as the fact that approximately one-third of the population perceives it to have a bitter aftertaste, has limited its use. 

Acesulfame K. Acesulfame K [55589-62-3] C H NO S -K, is an oxathia2iae derivative approximately 200 times as sweet as sucrose at a 3% concentration ia solutioa (70). It is approved for use as a nonnutritive sweeteaer ia 25 couatties (71), and ia the United States has approval for use in chewing gum, confectionery products, dry mixes for beverages, puddings, gelatins, and dairy product analogues, and as a tabletop sweetener (72). 

Other Sweeteners. Two other sweeteners, sucralose and cyclamates, are approved for use outside of the United States. Sucralose, a chlorinated derivative of sucrose which is 500—600 times as sweet as sugar, has received limited approval in Canada, and petitions for its approval are pending in the United States and Europe (71). Cyclamate sweeteners, once available in the United States, but now baimed because they caused bladder cancer in animals, are stiU available in Canada and Europe. Table 7 gives several examples of nonnutritive sweeteners that have been developed. 

Ice Crea.m, Ice cream is a frozen food dessert prepared from a mixture of dairy iugredients (16—35%), sweeteners (13—20%), stabilizers, emulsifiers, flavoriug, and fmits and nuts (qv). Ice cream has 10—20% milk fat and 8—15% nonfat solids with 38.3% (36—43%) total soHds. These iugredients can be varied, but the dairy ingredient soHds must total 20%. The dairy iugredients are milk or cream, and milk fat suppHed by milk, cream butter, or butter oil, as well as SNF suppHed by condensed whole or nonfat milk or dry milk. The quantities of these products are specified by standards. The milk fat provides the characteristic texture and body iu ice cream. Sweeteners are a blend of cane or beet sugar and com symp soHds. The quantity of these vary depending on the sweetness desired and the cost. 

Some peptides have special tastes. L-Aspartyl phenylalanine methyl ester is very sweet and is used as an artificial sweetener (see Sweeteners). In contrast, some oligopeptides (such as L-ornithinyltaurine HQ. and L-oriuthinyl-jB-alariine HQ), and glycine methyl or ethyl ester HQ have been found to have a very salty taste (27). 

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). 

Sweetener Relative sweetness Sweetener Relative sweetness... 

Fmctose is sweeter than sucrose at low temperatures (- S C) at higher temperatures, the reverse is tme. At 40°C, they have equal sweetness, the result of a temperature-induced shift in the percentages of a- and P-fmctose anomers. The taste of sucrose is synergistic with high intensity sweeteners (eg, sucralose and aspartame) and can be enhanced or prolonged by substances like glycerol monostearate, lecithin, and maltol (19). 

The sweetness of fmctose is 1.3—1.8 times that of sucrose (10). This property makes fmctose attractive as an alternative for sucrose and other commercially available sweeteners. Fmctose is probably sweetest ia comparison with sucrose when cold and freshly made up ia low concentrations at a slightly acidic pH (5). This relative sweetness difference is commonly attributed to changes ia fmctose stmcture when cold ( P-D-fmctopyranose(l), sweet) as compared to the stmcture when the sweetener is warm ( P-D-fmctofuranose (2), less sweet). Based on nmr spectroscopy and sensory panel evaluation of sweetness, however, it has been observed that the absolute sweetness of fmctose is the same at 5°C as at 50°C, and is not dependent on anomeric distribution (11). Rather, it maybe the sweetness of sucrose, which changes with temperature, that gives fmctose sweetness the appearance of becoming sweeter at low temperatures. 

Also notable is the unique sweetness response profile of fmctose compared to other sweeteners (3,4). In comparison with dextrose and sucrose, the sweetness of fmctose is more quickly perceived on the tongue, reaches its iatensity peak earlier, and dissipates more rapidly. Thus, the sweetness of fmctose enhances many food flavor systems, eg, fmits, chocolate, and spices such as cinnamon, cloves, and salt. By virtue of its early perception and rapid diminution, fmctose does not have the flavor-maskiag property of other common sugars. 

The sweetness of fmctose is enhanced by synergistic combiaations with sucrose (12) and high iatensity sweeteners (13), eg, aspartame, sacchatin, acesulfame K, and sucralose. Information on food appHcation is available (14,15). Fmctose also reduces the starch gelatinization temperature relative to sucrose ia baking appHcations (16—18). 

Hydrogenation of high maltose symps gives a mistuie of sugar alcohols, from which maltitol [585-88-6J (4) can be isolated in crystalline form. Maltitol is almost as sweet as sucrose (0.9 times) and has been promoted as a sweetener in various food apphcations (33). 

Sweetness is often an important characteristic of sugar alcohols in food and pharmaceutical applications. The property of sweetness is measured in a variety of ways and has a corresponding variability in ratings (218). Based on one or more test methods, erythritol and xyfitol are similar to or sweeter than sucrose (218,219). Sorbitol is about 60% as sweet as sucrose, and mannitol, D-arabinitol, ribitol, maltitol, isomalt, and lactitol are generally comparable to sorbitol (see Sweeteners). 

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