NORTHERN SUGAR INDUSTRY. 



41 



AVERAaE YIELD OF SINGLE MILLING. 



With a three-roll mill, especially adapted to working sorghum, I think 

 a yield of 55 to 60 per cent, in weight of juice is all that can be expected 

 with unstripped canes. In 1882 the Lafayette Sugar Company, in fif- 

 teen weighings of cane and bagasse, showed a yield on clean cane of 

 65 per cent. But this is higher than can generally be expected. As a 

 result of several years of observation and experience, I am convinced 

 that the average yield of three-roll mills on unstripped cane of all kinds 

 does not exceed 50 per cent. By double milling, with intervening steam- 

 ing or moistening with hot water, much better results are obtained. 



Unfortunately no exact data of the working of such mills are at handy 

 and I can but regard as extravagant the statements which have been 

 made which claim a yield of 75 to 80 per cent, of the weight of the cane 

 milled in juice. Experiments in this division have shown that sorghum 

 cane contains of water and Substances soluble therein about 89 per cent, 

 of its weight. 



A perfect extraction of the juice by milling, therefore, would give 89 

 pounds juice to each 100 pounds of cane. It is needless to add that no 

 system of milling now in use comes near realizing this ideal yield. 



PERCENTAGE OF JUICE EXTRACTED. 



The weight of juice extracted by the mill was 41.9 per cent, of the 

 weight of the cane ground. 



CANE WORKED FOR SUGAR. 



Of the total weight of 746,350 pounds of amber cane, all but 174,000 

 pounds were worked for sugar. The quantity of juice boiled for sugar 

 was 572,350x41.9=239,814 pounds. The percentage of sucrose in this 

 juice determined by the mean of the analyses of each tankful was S.77. 



The sugar not sucrose (invert sugar, optically inactive sugar, and 

 other substances reducing the alkaline copper tartrate mean of all the 

 analyses) was 4.00 per cent. Total sugars =.12.77 per cent. Total 

 solids=14.14 per cent. Solids not sugars=1.37 per cent. Coefficient 

 of purity =62. 



it will be of interest to compare these results with the analyses of 

 ripe Amber canes made in this division during the years 1882, '81, '80^ 

 and '79. 



Per cent^ 



For 1879, the average of sucrose (14th stage*) was 12. 44 



For 1879, the average of other sugars was 1. 1& 



For 1880, the average of sucrose (1,127 analysest) was 13.85 



For 1880, the average of other sugars was 1. 64 



For 1881, the average sucrose (59 analyses) was 15. 29 



For 1881, the average of other sugars was 1-62 



For 1882, the average of sucrose was 10. 48 



For 1882, the average of other sugars was 1. 33- 



For 1883, the average of sucrose (137 analyses) was 8. 77 



For 1883, the average of other sugars was 4. OO 



*Ag. Rept., 1880, '81, p. 452. 



+ Ag. Rept., 1880, '81, p. 493. 



