CANE SUGAR. 



material, 10 c.c. of a 4 per cent, solution ammonium molybdate, 10 c.c. water, 

 and '2 c.c. glacial acetic acid are heated at 95C. ; levulose in three minutes 

 gives a fine blue colouration ; all sugars give the same reaction in the presence 

 of mineral acids. The writer modifies this test as follows : To a suspected 

 water 2 per cent, of hydrochloric acid of 1*18 sp. gr. is added, placed in a test 

 tube, and heated on the water bath for five minutes ; an equal quantity of a 

 5 per cent, solution of ammonium molybdate is then added, and the heating 

 continued for five minutes ; in the presence of sugars a blue colouration is 

 produced, which may be compared with previously prepared samples. The 

 colour thus produced may be simulated by solutions of copper sulphate 

 prepared to represent the colouration produced by 1 part of sugar in 20,000, &c. 



Analysis of Waste Waters. Sugar is detected and estimated 

 in waste waters by Molisch's or PinofPs reactions given in a previous paragraph ; 

 if sugar is present in sufficient quantity, the waste waters may be concentrated 

 and the sugar determined by the polariscope, or as glucose after inversion. 



Analysis of Cattle Food or Molascuit. Cattle food is a 

 mixture of molasses and finely comminated megass, from 25 per cent, to 30 

 per cent, of the latter being used. It is usually sold on its percentage of 

 sugars expressed as glucose. The method used by the writer is as follows : 

 About five grms. of material are introduced into a funnel and washed with 

 successive quantities of water until all soluble matter is removed ; the united 

 washings are inverted, neutralized, made up to 1000 c.c., and the glucose 

 determined by one or other of the methods already given. The fibre is 

 determined by drying the insoluble residue to constant weight. 



A Soxhlet extractor may also be used for the separation of the soluble 

 matter from the fibre. 



The Analysis of Limestone and Lime. It is not general for 

 sugar factories to prepare their own lime, but in the carbonation process it is 

 necessary, and where a supply of limestone is abundant, as in Mauritius and 

 Barbados, it is cheaper to burn lime than to import. The choice of limestone 

 is important and it is advisable also to keep a check on the composition of the 

 purchased lime. 



Moisture. Dry 1-2 grms. to constant weight. 



Sand, Insoluble and Organic Matter. Dissolve about 1 grm. in hydro- 

 chloric acid, filter through a tared filter paper, wash and dry at 100 C. ; 

 weigh, giving the weight of sand, &c., ignite and weigh obtaining the sand, 

 the difference of the two weights giving the organic matter. 



Soluble Silica. Evaporate to complete dryness the filtrate from the 

 determination of the sand, &c. ; moisten the residue and again evaporate to 

 dryness, keeping the residue at a temperature of 120 C. for an hour after the 



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