CANE SUGAR. 



discontinuous process. Its disadvantages lie in its removing from the pro- 

 duct bodies of boiling point remote from that of alcohol and to which the 

 flavour of rum is due ; attempts have been made to restrict the term rum to 

 the product of discontinuous stills. 



Separation of Products of Fermentation. When using the 

 old forms of vat stills the bodies that have low boiling point pass over in the first 

 runnings, while the fatty acids and higher alcohols having higher boiling points 

 pass over in the last runnings ; between these comes over the main body of 

 the distillate ; the first and last runnings are collected separately and are called 

 feints or low wines. In the continuous type of still the bodies of low 

 boiling point are found in the cold feints, the fatty acids in the hot feints ; a 

 complete separation is however impossible, and all these bodies are found in 

 greater or less degree in the spirit, dependent on the care exercised by the 

 distiller. The boiling points of the principal constituents of rum are in degrees 

 Fahrenheit: Alcohol 173; formic acid 216; acetic acid 246; butyric 

 acid 315; capric acid 380; ethyl formate 129; ethyl acetate 168; ethyl 

 butyrate 241 ; ethyl caprate 322; formaldehyde 70. It will be seen that 

 ethyl acetate and alcohol have nearly the same boiling point, so that any 

 ethyl acetate present in the fermented wash will be totally recovered with 

 the rum ; the other bodies will be present in less quantity as their boiling 

 .point is more remote from that of alcohol ; the majority of these bodies 

 .are, however, volatile in steam and hence are present in the distillate in 

 larger quantity than would be supposed from their boiling point. 



Caramel. Caramel is the name given to the decomposition products 

 -obtained on heating sugar or glucose to temperatures in the neighbourhood 

 of 180C. ; a black brittle amorphous highly hygroscopic substance, which 

 reduces Eehling's solution, results. This body is certainly a mixture of various 

 bodies, of the chemistry of which nothing is known. The product when pre- 

 pared from pure sugar or glucose, and when care is taken to prevent local 

 superheating, is highly soluble in water and to a less degree in spirit ; there 

 are present, however, especially when the decomposition is pushed to extremes, 

 caramels which are insoluble in water and soluble in spirit. If these are 

 present in any notable quantity, a perfectly clear 40 O.P. spirit may give a 

 deposit when mixed with water, and to the presence of these caramels is to be 

 attributed one of the causes of faultiness in rum. 



Caramel produced by burning sugar is completely soluble in water in the 

 presence of alkalies, and the solution at the same time assumes a much darker 

 colour ; but caramels dissolved in spirit are precipitated by alkalies, the solution 

 becoming less coloured ; in the presence of alkalies the flavour of the caramel 



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