THE DETERMINATION OF CANE SUGAR 



determined, whence the polarization is calculated from the Brix determina- 

 tion. The results obtained by these different routines will vary following 

 the principles discussed at the beginning of this chapter. For strict control 

 work, the determinations should be made in the appropriate concentrations 

 of non-sugar. 



Filter Press Cake. As under Raw Sugar, but using only 25 grams to 

 compensate for the volume occupied by the insoluble matter. 



Determination of Sugar in Bagasse. The process always used is one of 

 aqueous digestion and extraction of the sugar in a determined volume of 

 water. A number of routines have been suggested and some of these are 

 described below.* 



Java Experiment Station Method. Twenty grams of finely divided material 

 are heated with 250 c.c. water and allowed to boil for fifteen minutes, the 



A- 



FIG. 335 



FIG. 336 



water evaporated being continually replaced by a drip from some convenient 

 vessel. After heating, cooling, and the addition of basic lead acetate, the 

 quantity of water remaining is determined by weight, to which is added that 

 introduced with the material. The polarization of the filtered extract 

 gives the polarization of the bagasse by calculation, or from a table. 



Norris's Method. 66 This method employs the " double cooker," shown 

 in Fig. 335, which is of dimensions : 



A. 6 ins. high by 5 J ins. diameter. 



B. 4^ ins. high by 4^ ins. diameter. 



One hundred grams finely divided material are placed in vessel B, with 

 500 c.c. hot water and 5 c.c. of 5 per cent, solution of sodium carbonate. 

 Water is placed in the vessel A and boiled for one hour. Every fifteen 

 minutes the material in B is pressed down by the tamp C. After cooling, 

 the weight of the extract is determined, the extract is pressed out, filtered 



* The exactness of the usual bagasse analysis schemes has been subject to controversy. Pellet 65 found that 

 ordinary boiling failed to extract all the sugar. Geerligs 66 found that prolonged boiling gave higher results, which 

 he attributed to the gradual solution of hemi-celluloses. Morris 66 did not confirm this, but found that the fineness 

 of division very materially affects the rate of extraction. 



