THE CONCENTRATION OF THE SYRUP TO MASSECUITE. 



lation depends on the type of sugar required ; when a large crystal is desired 

 only a small quantity of syrup is granulated. This process is known as 

 ' graining low down.' Forming grain from a large quantity of syrup, known 

 as ' graining high up,' will result in a sugar with small crystals. After the 

 granulation has been effected, the next step is to feed the grain with charges 

 of syrup, the object of the operator being to deposit the sugar that now 

 separates on the crystals already formed and not to allow it to form new 

 crystals ('false grain' or 'dust'). To avoid the occurrence of a second crop of 

 crystals the pan must be boiled evenly, there must be no sudden alteration in 

 temperature due to variation in quantity of steam or injection water, or by 

 taking in too large charges of cold syrup which, by locally reducing the tem- 

 perature in a part of the pan, causes a deposit of a fresh crop of crystals. 

 The scheme of feeding the pan continuously instead of intermittently is 

 dangerous, as, owing to alterations in steam pressure over which the pan boiler 

 has no control, slight variations may result in false grain being formed. 

 Should this occur from any cause pan boilers have two methods for its removal: 

 one is to partly cut off the injection water and so raise the temperature within 

 the pan, the finer crystals dissolving ; the second method is to take in a large 

 charge of syrup or even juice which dissolves the finer crystals; this last method 

 is termed by pan boilers 'washing.' When making large grained sugars for 

 direct consumption skilful pan boilers frequently, during the boiling of the 

 strike, take in large charges of syrup for the purpose of dissolving the smaller 

 crystals ; this process is called ' opening out ' or ' boiling free,' and in skilful 

 hands gives large, fine, bold crystals, but with less skilled operators is liable to 

 cause a serious deposit of false grain. Winter's patent, referred to later, 

 gives another means of removing the smaller crystals. 



W T hen the pan is full no more syrup is taken in, but the temperature is 

 gradually raised by cutting off the injection water until the striking point, 

 which can only be determined by experience, is reached ; the water content to 

 which a strike can be boiled depends largely on the purity of the juice, but it 

 is also controlled by such influences as the size of the pan outlet, and time 

 available for striking the pan. The greater the purity the less may be the 

 water content, although an impure massecuite with more water than a pure 

 one may still have a greater degree Brix. After a pan has been once filled 

 it is often advisable to strike out only half, and to continue boiling on the 

 remainder ; this process is known as ' doubling,' and the discharged masse- 

 cuite is termed the first cut ' ; the object is to save time and to obtain 

 a large grained sugar in the second and subsequent cuts. This process 

 may, with exceptionally pure juices, be continued four or five times, whilst 

 juices of low purity may not give a single 'double* ; in any case there is always 

 a point beyond which the sugar crystal refuses to grow, and any attempt to 

 further increase its size ends in a fresh deposit of minute crystals. 



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