THE DETERMINATION OF CANE SUGAR 



ill 



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

 tion. The results obtained by these different routines vdU 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 bv 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 

 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 number of routines have been suggested and some of these are 



i^ 



Fig. 



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. 



Xorris's Method. ^^ — This method employs the " double cooker," shown 

 in Fig. 335, which is of dimensions : — 



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



B. 4I ins. high b}* 4^ ins. diameter. 



One hundred grams finely di\-ided matericd 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. Ever\' 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*^ found that 

 ordmar>- boiling failed to extract all the sugar. Geerligs** found that prolonged boiling gave higher results, which 

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

 of di\Tsion very materially afiects the rate of extraction. 



