FERMENTATION WITH SPECIAL REFERENCE TO THE SUGAR HOUSE 



undergoes a complete change, and at the same time gives off a peculiar 

 odour. 



A process which was long kept a trade secret and used, it has been stated, 

 especially for colouring rums, consisted in burning sugar in the presence of 

 alkalies ; the proportions used were 60 parts of sugar and 2 parts of sodium 

 or I' 5 parts of caustic soda. This process is referred to as Asrymusry's; but in 

 view of what has been said above on the action of alkalies on caramel dissolved 

 in spirit, it would hardly promise success. The temperature at which the 

 conversion of sugar into caramel takes place has been stated by different 

 authorities as between 160 C. and 250 C. 



When caramel is used for colouring rum, two points have to be considered; 

 the caramel should reduce the strength of the spirit as little as possible, and 

 give to the rum a sugary flavour. To obtain the latter effect the molasses or 

 sugar syrup should not be burned too far, but in this case the amount 

 of caramel required to give the necessary depth of colour so much increases 

 the density of the spirit that there is a large apparent loss. 



The usual method of preparing caramel is as under : Into an iron pot of 

 about 200 gallons' capacity, usually an old iron tayche, are introduced 40 to 50 

 gallons of molasses, and water added to a density of about 1'25; instead of 

 molasses a syrup of sugar and water of the same density is sometimes used. A 

 brick oven is built under the pot, and a brisk fire kept up ; the molasses or 

 syrup must be kept in continual motion, preferably by a mechanical stirrer. 

 The sugar solution rapidly darkens, and in from 60 to 90 minutes is quite 

 black. The usual test to show if the caramel is sufficiently burned is to remove 

 a portion on a stick, and after cooling, to break the caramel with the finger ; it 

 should be quite brittle. Another test is to drop a globule of the burnt caramel 

 into water, the floating of the globule being an indication that the caramel is 

 sufficiently burned; when either of these tests obtains, the caramel will 

 colour rum reasonably well, but to obtain a low obscuration the burning must be 

 continued longer. When the point at which the caramel is sufficiently burned 

 is decided, the fire is drawn and sufficient water added to permit of easy 

 carriage to the rum store. 



The higher the temperature at which the caramel is burned, the less is 

 required to produce the necessary depth of colour, and the apparent loss of 

 strength is lower ; the after treatment in the rum store has also an effect on 

 the caramel. If the crude colour be repeatedly treated with strong 60 O.P. to 

 70 O.P. spirit, the colour solution allowed to settle, and the clear colour drawn 

 off, eventually a colour is obtained which gives a barely appreciable obscura- 

 tion ; this process is too lengthy to carry out in practice, but a colour burnt as 

 described above and treated once, bulk for bulk, with white rum from the still, 



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