Sucrose reducing properties

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. 

Question Why doesn t sucrose, another disaccharide, have reducing properties ... 

Saccharose (sucrose) does not show reducing properties as it does not contain a carbonyl group (aldehyde, a-hydroxy ketone or hemiacetal group). Hence it does not react with Tollens and Fehling s reagents. 

In the molecule of sucrose, glucose is present in the a-glucopyranose form and fructose in the y3-fructofuranose form. The two sugars are joined by their two reducing groups and as a result sucrose has no reducing properties. 

Formation of D-fructo ranosyl carboxonium (oxycarbenium) ions by reaction of free sucrose-OH-groups to a mixture of 41% oligosaccharides and 46% polysaccharides with hydrophilic, waterabsorbing properties with added alcohols, they produce glycosides, the properties of which are determined by the nature of the alcohols Possible drawbacks in these chemical modifications may arise from the tendency of inversion, which leads to reducing properties, acidic or alkaline degradation and color formation, depending on the environmental conditions of the reaction. 

In addition, Montenegro et al., (2007) determined that the photosensitized RF-mediated degradation of vitamins A, D3, and RF itself in skimmed milk was strongly reduced by the addition of small amounts of lycopene-gum arabic-sucrose microcapsules, prepared by spray-drying. Under these conditions, the bulk properties of the skimmed milk were unmodified. The main photoprotection mechanism of the milk vitamins was the efficient quenching of the 3Rf by the protein moiety of GA. Small contributions (<5%) to the total photoprotection percentage was due to both inner filter effect and 1O2 quenching by the microencapsulated lycopene. 

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