How can we calculate the reducing sugar in sorbitol as per ip monograph

how can we calculate the reducing sugar in sorbitol as per ip monograph

You can either perform gravimetric analysis and weigh the residue of Feric oxide precipitate obtained by quantative estimation. Apply conversion factor to the weight of Ferric oxide and calculate reducing sugar in Sorbitol. Alternatively, perform volumetric analysis by titration of Sorbitol solution against Felling A and B mixture under boiling condition. Choice of method depends upon reducing sugar present in the sample of Sorbitol.