Humectancy and Hygroscopicity

A hygroscopic material absorbs moisture from its surrounding atmosphere, while a humectant material is one that resists changes in relative moisture content. The gain or loss of moisture in a com syrup is dependent on the relative humidity of the atmosphere surrounding the syrup. Moisture absorption values for several sweeteners are shown in Table 21.16.79 

Starch-derived syrups are able to crystallize, depending on the type of carbohydrates present, the solids level and the temperature. This property can be used to advantage, as in the manufacture of hard candy, or can be one to be avoided, as in the case of 

Sugar Relative Percent moisture absorption from 1 to 76 days (25°C) 

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 

30 DE acid-converted syrup 36 DE acid-converted syrup 42 DE acid-converted syrup 54 DE acid-converted syrup 62 DE acid-converted syrup HFS (42% fructose) 

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