Honey

• DETERMINATION OF FRUCTOSE GLUCOSE RATIO

  Pipette out 50 ml of the prepared honey solution (used for TRS determination) in to a 500ml iodine value flask add 40ml of iodine solution and 25ml NaOH. Stopper the flask and keep in dark for 20 minutes acidify with 5ml of sulfuric acid and titrate quickly against standard sodium thiosulphate from a burette. Conduct a blank using 50ml of water instead of honey solution.

Calculation

Approximate glucose percentage =  (V-S)*0.004502*N*100
                                                                        (W/10)*0.05

Where

             V=volume of sodium thiosulphate required for blank.
             S= volume of sodium thiosulphate required for sample.
             N=normality of sodium thiosulphate.
            W=weight of honey in 50ml of honey solution.

Approximate fructose %=   approximate  TRS   -      approximate glucose% 
                                                                             0.925

               True Glucose%= appro.glucose % - ( appro.fructose%*0.012)

                True fructose%=   appro.TRS - true glucose %
                                                              0.925

                          True TRS= True glucose + True fructose

   Fructose glucose ratio =       True fructose                                     
                                                    True glucose

Example:-

          Appro.glucose= (44.3-28)*0.004502*100*0.0506534
                                               0.05*0.20355
                                    = 36.52

           Appro.fructose= 73.011-36.52
                                         0.925
                                     = 39.45

               True glucose= 36.52-(39.45*0.012)
                                     = 36.0466

               True fructose =73.011-36.0466
                                               0.925
                                       = 39.96
Fructose glucose ratio =   39.96
                                             36.0466
                                        =1.1085

         True TRS               = 36.0466+39.96
                                         =76.008.