Sweetness value

Dry crystalline fructose is reported to have a sweetness level of 180 on a scale in which sucrose is represented at 100 (Andres, 1977). In cool, weak solutions and at lower pH, sweetness value is reported to be 140-150. At neutral pH or higher temperatures, the sweetness level drops, and at 50cC (122°P) sweetness equals that of a corresponding sucrose solution. A synergistic sweetness effect is reported between sucrose and fructose. A 40-60% fructose/sucrose mixture in a 100% water solution is sweeter than either component under comparable conditions (Unpublished report, University of Helsinki, 1972). 

Sweetness is an important and easily identifiable characteristic of glucose- and fructose-containing sweeteners. The sensation of sweetness has been extensively studied.80-82 Shallenberger83 defines sweetness as a primary taste. He furthermore asserts that no two substances can have the same taste. Thus, when compared to sucrose, no other sweetener will have the unique properties of sweetness onset, duration and intensity of sucrose. It is possible to compare the relative sweetness values of various sweeteners, as shown in Table 21.17,84 but it must be kept in mind that these are relative values. There will be variations in onset, which is a function of the chirality of the sweetener,85 variations in duration, which is a function of the molecular weight profile and is impacted by the viscosity, and changes in intensity, which is affected by... 

Table 21.17 Relative sweetness values of various sweetener84...

Most tests have shown D-fructose to be the sweetest of the sugars, although the actual ratios between the various sugars depend to a considerable extent on the taster and on the methods and conditions adopted for the comparison. Compared to a sweetness value for sucrose of 100, that for D-fructose has been reported as varying from 103 to 173. The alleged relative sweetnesses of some sugars and other organic compounds can be found in Ref. 1. 

In a mixture of sugars, if the sweetness values of the components are calculated in terms of dextrose sweetness, the values become additive rather than supplemental as they appear to be when calculated in terms of sucrose sweetness as the standard (3). The sugar and corn products industries, through the nature of their products, have given the confectioner a flexibility and a challenge to his creative abilities for producing new candy. 

A great many substances are known to produce the sensation of sweetness but, although this quality must stem from particular features of their chemical structure, it has not, so far, been possible to determine what these are. Most sugars and sugar derivatives have a sweet taste but so do many other totally unrelated compounds. Since the chemical basis of sweetness is unknown it is not possible to measure the property by scientific means and methods of sweetness measurement are necessarily subjective and include (1) equal sweetness matches in which the concentration that produces a sensation equivalent to that of a standard solution, usually sucrose, is determined and (2) threshold measurements, which involve finding the lowest detectable concentration of sweetener. Approximate relative sweetness values are given in Table 10.10 but there are, in addition, certain qualities of sweetness that are not easy to define. Some sweeteners lack the clean clear taste of sucrose and some have an unpleasant aftertaste. 

Sweetness is related to saccharose sweetness (= 1) the values are affected by sweetener concentration. Sweetness value is strongly influenced by syrup composition. 

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... 

A persistent idea is that there is a very small number of flavor quaUties or characteristics, called primaries, each detected by a different kind of receptor site in the sensory organ. It is thought that each of these primary sites can be excited independently but that some chemicals can react with more than one site producing the perception of several flavor quaUties simultaneously (12). Sweet, sour, salty, bitter, and umami quaUties are generally accepted as five of the primaries for taste sucrose, hydrochloric acid, sodium chloride, quinine, and glutamate, respectively, are compounds that have these primary tastes. Sucrose is only sweet, quinine is only bitter, etc saccharin, however, is slightly bitter as well as sweet and its Stevens law exponent is 0.8, between that for purely sweet (1.5) and purely bitter (0.6) compounds (34). There is evidence that all compounds with the same primary taste characteristic have the same psychophysical exponent even though they may have different threshold values (24). The flavor of a complex food can be described as a combination of a smaller number of flavor primaries, each with an associated intensity. A flavor may be described as a vector in which the primaries make up the coordinates of the flavor space. 

Sandalwood Oil, East Indian. The use of sandalwood oil for its perfumery value is ancient, probably extending back some 4000 years. Oil from the powdered wood and roots of the tree Santalum album L. is produced primarily in India, under government control. Good quaUty oil is a pale yellow to yellow viscous Hquid characterized by an extremely soft, sweet—woody, almost ariimal—balsarnic odor. The extreme tenacity of the aroma makes it an ideal blender—fixative for woody-Oriental—floral fragrance bases. It also finds extensive use for the codistillation of other essential oils, such as rose, especially in India. There the so-called attars are made with sandalwood oil distilled over the flowers or by distillation of these flowers into sandalwood oil. The principal constituents of sandalwood oil are shown in Table 11 (37) and Figure 2. 

Bergamot. Bergamot oil is produced by cold expression from peels of fmits from the small citms tree. Citrus bergamia. The fmits are inedible and of httle value. Bergamot is grown mainly in southern Italy and northern and western Africa. The oil is used to impart a sweet freshness to perfumes. Its largest chemical constituent, to the extent of 35—40%, is linalyl acetate [115-95-7] (1), with a much smaller amount of citral [5392-40-5] (2) as an important odor contributor. 

L-Amino acid Threshold value, mg/dL Sweet Sour Bitter Salty Umami... 

Odor data for the various amyl alcohols is limited. The lowest perceptible limit for 1-pentanol and / fZ-amyl alcohol are 10 and 0.04 ppm, respectively (135). tert-Axa[. alcohol has a threshold value of 2.3 ppm (and a 100% recognition level of 0.23 ppm) 3-methyl-1-butanol has an odor threshold of 7.0 ppm. The odor of 1-pentanol has been described as sweet and pleasant whereas that of 3-methyl-2-butanol is sour (135). 

HES containing 90% fmctose is used in low calorie or specialty foods because of its high sweetness and, therefore, reduced usage level and lower caloric value. Crystalline fmctose is essentially pure and used at a level that provides sweetness at a lower caloric level than other sweeteners (qv). Initial use was in diet and nutritious foods but appHcation has now been extended to many other food areas, such as powdered beverages, dry mix desserts, dairy products, and confections. 

Sweetness is primarily a function of the levels of dextrose and maltose present and therefore is related to DE. Other properties that increase with increasing DE value are flavor enhancement, flavor transfer, freezing-point depression, and osmotic pressure. Properties that increase with decreasing DE value are bodying contribution, cohesiveness, foam stabilization, and prevention of sugar crystallization. Com symp functional properties have been described in detail (52). 

Natural gas with H2S or other sulfur compounds present is called sour gas, while gas with only CO2 is called sweet. Both H2S and CO2 are undesirable, as they cause corrosion and reduce the heating value and thus the sales value of the gas. In addition, H2S may be lethal in very small quantities. Table 7-1 shows physiological effects of H2S concentrations in air. 

The higher aliphatic alcohols, from octyl alcohol upwards, have-recently been introduced as perfume materials with considerable success. Only one or two of them, such as nonyl and undeeylenic alcohols, have so far been detected as natural constituents of essential oils, but other members of the series are prepared artificially, and are employed in minute quantities in the preparation of perfumes with characteristic, fruity bouquets. These alcohols are greatly diminished in perfume value by traces of impurities. According to H. J. Prins, the first interesting member of the series is octyl alcohol it has a very sweet, rose-like odour, and is especially suitable for giving a rose perfume that pecnliar sweet smell which distinguishes a rose from a rose perfume. This feature of the aliphatic alcohols diminishes in the series from Cg to Cjg. 

Fermentation of Sweet Sorghum into Added Value Biopolymer of Polyhydroxyalkanoates (PHAs)... 

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