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NEUTRAL VERSUS ACID CLARIFICATION. 



In all Louisiana sugar-houses where sulphur is used the juices are 

 left slightly acid for the purpose of 'securing an improved color in all 

 the products from first sugar to final molasses inclusive. This practice 

 is followed both in open-kettle and vacuum-pan sugar-houses. 



The great trouble in working such juices is, naturally, the inversion 

 caused by the presence of a free acid. A very slight acidity is all that 

 is pecessary to secure the desired color in the production of yellow 

 clarified sugars, but even in skilled hands this acidity is very difficult 

 to control, and under the charge of the ordinary Louisiana clarifier- 

 man the juice is left first at one extreme and then at the other, with a 

 tendency always to the more acid juice. 



In the manufacture of white sugar the evil is, of course, intensified 

 by higher degrees of acidity sought. The lack of knowledge and care 

 has been so marked in most cases that the owners themselves were 

 ignorant even that it was possible for such a loss to occur. 



Only in a very few places, and even in these but for a few years, have 

 any attempts been made to give the juice a practical chemical treat- 

 ment. In most places where this has been done a considerable inver- 

 sion has been found in working the acid juices. To overcome this loss 

 by inversion the juices are limed to neutrality. This practice, how- 

 ever, lowers the quality of the sugar, for as soon as the juice loses its 

 acidity it fails to give so brilliant a sugar, because of the formation of 

 calcic glucates and other dark-colored compounds; hence it is necessary 

 that a sufficient amount of additional sugar be recovered by the neutral 

 clarification to overcome the difference in price of the sugar from an 

 acid clarification. 



The last two runs of the season were selected for a trial of the relative 

 merits of the two methods of clarification, and a tabulated statement 

 of the work done is given below : 



The selection of these two runs for the trial proved to be a very un- 

 fortunate one, the difference in the quality of the cane being very marked. 

 With no other difficulty than this a strict comparison of results would 



