Glucose relative sweetness

The high sweetness of fructose combined with that of glucose means invert sugar is sweeter than sucrose, so it provides a cheaper, less calorific sweetener than sucrose. The relative sweetness figures for sucrose, glucose and fructose are 1.0, 0.7 and 1.7 respectively. Honey is also composed mainly of invert sugar. 

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... 

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... 

For a molecule to taste sweet, it must bind to a receptor on a taste bud cell of the tongue. The binding of this molecule causes a nerve impulse to pass from the taste bud to the brain, where the molecule is interpreted as being sweet. Sugars differ in their degree of sweetness. The relative sweetness of glucose is 1.00, that of sucrose is 1.45, and that of fmctose, the sweetest of all sugars, is 1.65. Developers of synthetic sweeteners must consider several factors—such as toxicity, stability, and cost—in addition to taste. 

The relative sweetness of a number of sugars and artificial sweeteners is given in Table 23.3. Somewhat lower thresholds than those given in Table 23.2 were obtained for sucrose (0 017 %), fructose (0 016 %), glucose (0-132 %), and lactose (0-0160%) when expressed as the concentration at which 50% of the responses correctly distinguished the sugar solution from a distilled water blank [23]. 

The taste sense and the relative sweetness of sugars and other sweet substances have been critically reviewed (77). At certain concentrations mixtures of isosweet solutions of sucrose and corn sirup are slightly sweeter than either parent solution. a-D-Glucose is somewhat sweeter than jS-D-glucose. Therefore, fresh a-D-glucose solutions are sweeter than those in which there is an equilibrium between the a- and j3-forms. Because fructose is almost twice as sweet as glucose, it would seem that inversion of sucrose ought to increase its sweetness. This occurs, but it is not noticeable at concentrations below 10%. 

Table 10.16. Relative sweetness of saccharose, glucose, fructose and lactose ...

The most important hexitols are o-glucitol and D-mannitol. The most important pentitol is xyhtol. The relative sweetness of both hexitols (in 10% solutions) and xyhtol, compared with saccharose, is about 60 and 100%, respectively. AU three polyols have very Kttle effect on blood glucose level and are therefore used as sweeteners for diabetics. However, their content must be included in the total energy intake. They exhibit mild laxative effects (such as prunes, which contain higher amounts ofglucitol than other fruits). 

Acid or enzymatic hydrolysis of sucrose, inversion, produces an equimolar mixture of n-glucose and n-fructose known as invert sugar. Invert sugar is used as a food additive substance, usually in the form of syrup (relative sweetness is 95-105% of saccharose sweetness). It also serves as a starting material for obtaining d-glucose and D-fructose, the sweeteners mannitol and glucitol and other substances. 

Diabetes mellitus ( sweet urine ) involves relative over-production of glucose by the liver and under-utilization by other organs. Diabetes is the most serious metabolic disease in terms of its social impact. Obesity and the indulgent Western diet correlates with mature age diabetes. Type 1 diabetes (juvenile diabetes) typically manifests at less than 20 years from autoimmune destruction of the insulin-producing pancreatic (3 cells. Type 1 diabetes is insulin-dependent diabetes mellitus (IDDM) and is fatal without exogenous insulin. Type 2 diabetes mellitus (mature age diabetes) occurs later in life and typically involves both deficient insulin production and insulin resistance , that is, the target cells are less responsive to insulin. Type 2 diabetes is initially non-insulin-dependent diabetes (NIDDM) but insulin therapy (in addition to oral antidiabetics) may eventually be required. Hyperglycaemia due... 

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