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MANUFACTURE OF SUGAR. 



on some sent me by my friend Mr. Best, from " Black- 

 rnans," found adhering to the gutter by which the juice 

 was conveyed from the mill, and which, after having been 

 kept nearly twelve months, still retained the qualities of a 

 ferment." This substance is observed by every one 

 employed in sugar manufacture. It adheres to the sieves, 

 pipes, and gutters through which the cold juice passes, is 

 slimy to the touch, and, when examined closely, appears in 

 globular particles, which are, no doubt, aggregates of 

 smaller ones, like the roe of a fish. These particles can be 

 removed by filtration, as they are insoluble, or nearly so, 

 in water; but as gluten is dissolved by alkaline lyes, it 

 should be removed before the addition of lime. 



Caseine exists in cane-juice in a soluble form, and is not 

 like albumen coagulable by heat. In order to effect its 

 coagulation, a little lime must be used, care being taken 

 not to use it in excess. In treating of this substance, Dr. 

 Evans remarks, — " When cane-juice, which has been 

 already boiled and filtered, is submitted to the action of 

 heat a second time, the flocculent particles which separated 

 from the liquid during the first ebullition, are not now 

 observed, but in place of them a thin film is seen to form 

 on the surface. A similar effect is produced on all liquids 

 which contain caseine in solution. We have a familiar 

 instance of this in boiling milk. It has been already 

 stated, that caseine is one of the proteine compounds 

 found in cane-juice, in which it is held in solution by the 

 presence of a vegetable acid, or acid salt, in the same way 



