Of sucrose

C (decomp.) It is made by the oxidation of toluene-o-sulphonamide with alkaline permanganate. Saccharin has about 550 times the sweetening power of sucrose, and is used extensively as a sweetening agent, usually in the form of the sodium salt. The use of saccharin is restricted in the U.S. 

Does not reduce ammoniacal silver nitrate or Fehling s solution. If, however, the sucrose solution is warmed for some time with the reagent in question, slight hydrolysis to glucose and fructose does take place and reduction then occurs occasionally samples of sucrose will rapidly give a silver mirror, presumably owing to impurities. 

Hydrolysis by acids. Sucrose is readily hydrolysed by dilute acids. Dissolve 0 5 g. of sucrose in 5 ml. of water, add 2 ml. of dil. H2SO4 and heat in a boiling water-bath for 5 minutes. Cool and show that the solution has reducing properties, and will form glucosazone. Note that the excess of acid must be neutralised before carrying out the reduction tests. 

Yeast contains a number of enzymes, more particularly inyertase and zymase. Invertase catalyses the hydrolysis of sucrose to glucose and fructose (cf. the catalysis of this reaction by acids, p. 369). 

Sucrose is dextro-rotatory. Fructose shows a laevo-rotation greater in magnitude than the dextro-rotation shown by glucose. Hence as the hydrolysis of sucrose proceeds, the dextro-rotation gradually falls to zero and the solution finally shows a laevo-rotation. This hydrolysis is therefore sometimes called inversion and so the enzyme which catalyses the reaction is known as " invertase. Its more systematic name is, however, sucrase. 

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... 

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