136 MANUAL FOR SUGAR GROWERS. 



while the mineral matter serves to supply plant- 

 food, which is quite as necessary to the yeast-plant 

 as to any other vegetable organism. 



The value of rum depends largely on its flavour 

 and aroma, and as the substances conferring the 

 distinctive character are very volatile they are 

 found in greatest quantity in the first runnings from 

 the still; hence stills of the old or discontinuous 

 type are often preferred, as by this means the first 

 half of the returns, or any desired portion, can be 

 kept separate in order to produce a spirit of first 

 quality. From the continuous stills the spirit flows 

 in a stream of almost unvarying quality, and in this 

 case it is impossible to separate the product into 

 portions differing in flavour and aroma. 



Bum is usually coloured by means of burnt 

 sugar. The colouring matter is prepared by heat- 

 ing muscovado sugar in an iron pan until it is con- 

 verted into caramel, having a fine black colour. 

 When sufficiently heated the fire is withdrawn, and 

 strong proof rum is added, the whole being briskly 

 stirred meanwhile. This solution is added to rum 

 in such quantity as to produce the desired colour. 



