SUGAR-CANS 516 



by a cut-off, the amount of heat, and thus to avoid any 

 danger of scorching the sirup. 



After being expressed by grinding, the fresh juice is 

 strained. In addition, it is sometimes strained through 

 a barrel of black moss. From the strainer the juice is 

 conveyed to the evaporator. Here it is heated rather 

 slowly. Heat causes the solid impurities to coagulate or 

 collect in masses of scum. This scum is removed before 

 boiling begins, and repeated skimmings remove all other 

 scum that rises. The boiling is continued in the next two 

 compartments of the evaporator until the hot sirup has 

 a ropy consistency, or, better still, until a Baume hy- 

 drometer, dropped into a slender deep vessel of hot sirup, 

 sinks to the mark on the scale indicating a density of 

 34. This instrument, costing only about $1, is a far 

 safer guide as to when to stop the cooking than is the 

 eye, even of an experienced sirup maker. The use of a 

 hydrometer is essential for all who would make a uniform 

 grade of sirup. 



500. Preventing sirup from turning to sugar. The 

 first aim in making sirup is to produce an article of an 

 agreeable flavor and nearly clear, or of bright color. The 

 use of immature cane or of cane injudiciously fertilized 

 results in injury to the flavor and appearance of the sirup. 



Another important aim in making sirup is to make a 

 product that will not, at a later date, crystallize or turn to 

 sugar. The larger the proportion of glucose (or non- 

 crystallizable sugar) in the sirup the less is the danger of 

 the sirup turning to sugar. 



Conditions favorable to a large proportion of glucose, and hence 

 to a sirup not easily crystallized, are the following : 



