20 



NORTHERN SUGAR INDUSTRY. 



maxima. Canes cut and left in the field, exposed to hot September 

 suns and cool September nights, will soon have all their sucrose de- 

 stroyed. This inversion is doubtless due to a kind of fermentation, 

 without any marked vinous or other common character. Canes thus 

 changed are still fit for sirup-making, but are worse than useless for 

 the production of sugar. 



In silos, as I have already shown, where the changes of temperature 

 are moderate and slow, the canes may be kept for.a long time without 

 undergoing any serious deterioration. 



It could be reasonably inferred from these facts that sudden tempera- 

 ture changes injure the delicate cell structure of the cane and thus by the 

 rupture of the cells favor the process of inversion. No histological in- 

 vestigations have been made, however, to confirm this supposition. It 

 may be that the presence of anoptoseand a trace of invert sugar mixed 

 with the sucrose in the cells greatly facilitates this change — a danger 

 which the sugar in the beet cells is not subject to. The sorghum is 

 much more subject to this inversion change than the tropical cane, as I 

 have said. It is not uncommon in the South to have three or four days 

 run of cane on hand at the mill; a method of x)rocedure that would be 

 attended with disastrous results with sorghum. 



In a sample of Louisiana cane sent to the President and thence to my 

 division for analysis, I found nearly 16 per cent, of sucrose and little 

 more than 1 per cent, of other sugars. The canes had been cut at least 

 two weeks. 



By this expression I mean the proportion of sugar which can be ob- 

 tained in a dry crystallized form from the canes. Its amount depends 

 on the percentage of juice extracted from the cane, and the ratio of 

 sucrose to the other bodies in the juice. 



I will not stop here to consider the question of the expression of the 

 juice, a subject which has been discussed in a special rei)ort.* I will as- 

 sume for the present, and the assumption will not be far from the truth, 

 that the amount of juice expressed will average about one-half the 

 weight of the cane. Long experience has shown that each equivalent 

 of substance not sugar in the juice prevents a like quantity of sucrose 

 from being obtained in a crystalline state. To this we must add another 

 result of experience, viz: that about 5 per cent, of the sucrose is lost 

 in the process of evaporation. 



Apply these data to a cane yielding a juice containing 10 \)er cent, su- 



ANALYSIS OF LOUISIANA CANES DECEMBER 11. 



Sucrose 



Other sugars 



Per cent. 

 ... 15.68 

 ... 1.13 



AVAILABLE SUGAR. 



I* Diffusion applied to Sorghum Cane. Chemical Division, United States Dejiart- 

 meut Agriculture. Bulletin No. 2. 



