Properties of ing. Flashcards
Sucrose is composed of?
one molecule of glucose and one molecule of fructose, a-D-glucopyranosyl-B-D-fructofuranoside.
where the Sucrose is more conc.?
more concentrated in sugarcane, Saccharum officinarum, and the sugar beet, Beta vulgaris, the latter in temperate zones.
Process of sucrose?
juice is extracted, purified, and concentrated to syrup. Sucrose is crystallized from the syrup by serial crystallization; the residual viscous syrup is molasses.
range of white sugar products
solid granulated, powdered, cubes, liquid sucrose, and invert syrups (blends of sucrose, glucose, and fructose). Primarily from sugarcane come brown sugars, edible molasses, golden syrups, and dark cane syrups.
Commercial refined sugar contains about ____ percent of
sucrose.
99.99
What type of glycosidic bond is present in sucrose, and how does it influence its chemical behavior?
While all monosaccharides (sugars containing a single sugar unit) are reducing sugars, sucrose is a cyclic disaccharide (made from two sugar units, glucose and fructose) and lacks a free aldehyde group because the aldehyde groups on both the glucose and fructose are bonded through [glycosidic bond (a 1- 2)] that hold the two units together
In hydrolysis of sucrose, what is form in the presence of hydrogen ions?
a tautomeric mixture of the a- and ß-cyclic,
and the aliphatic forms of D-glucose and D-fructose is formed
In alkaline decomposition, when sugar is heated in the presence of -OH ions, what substances are formed?
furfural, 5-hydroxy-methyl-2-furfural, methylglyoxyl, glyceraldehyde, , acetone, lactic acid, acetic acid, formic acid, carbon dioxide,
What happens when sucrose undergoes hydrogenation in the presence of metallic catalysts?
Sucrose can be reduced by hydrogen in the presence of metallic catalyzers.
The main products of the hydrogénation are D-mannitol, D-sorbitol, glycerol,
propylene glycol, ethylene glycol, isopropyl alcohol, methyl alcohol, acetol,
tetrahydrofuran derivatives etc
