The conversion of an optically pure isomer (enantiomer) into a mixture of equal amounts of both dextrose and levo forms is called as
When an equal amount of d & l isomers are present, the resulting mixture has no optical activity since the activities of each isomer cancel each other. Such a mixture is said to be `Racemic' or (DL) mixture

"The transformation of half of the molecules of an optically active enantiomer (pure isomer) into molecules which possess exactly the opposite (mirror image configuration) with the resultant complete loss of rotatory power because of statistical balance between equal numbers of dextrose & levo-rotatory molecules is called Racemization' 
- Dorland's Medical Dictionary
Polymerization
Stereoisomerization
Racemization
Fractionation