221 



exposed to the air any considerable length of time before it is heated, 

 the albumen and other nitrogenous substances will begin to evolve am- 

 nrionia, the presence of which interferes materially with the crystalliza- 

 tion of sugar. But suppose the albumen has been promptly coagulated 

 and the defecation has removed such substances as pectose, gums, &c., 

 yet there remains in solution the acids which tend constantly to convert 

 crystallizable sugar into glucose, which is practically uncrystallizable. 

 It is an urgent necessity that* these should be neutralized as soon as 

 possible. Caustic lime is commonly used for this purpose; but in the 

 presence of bases, sugar plays the part of an acid, and enters readily 

 into combination with these. This compound with lime has a bitter 

 taste, and is very soluble in cold water. Its solution, however, if toler- 

 ably concentrated, becomes opaque when heated, and presents an appear- 

 ance of coagulation, resembling that of white of egg. (Miller.) In the 

 presence of this j^eculiar substance the crystallization of sugar is inter- 

 fered with, and thus the loss is much more than that taken up by the 

 lime. In this state the compound of sugar and lime may be removed 

 by bone-black, but still the loss of sugar is considerable. Another 

 effect is produced by the use of caustic lime. Potassa and soda exist in 

 the beet juice in the form of carbonates, but the presence of lime im- 

 mediately reduces them to the caustic form, and they take up sugar to 

 supply the place of carbonic acid which they have lost. The proportion 

 of these alkalies in the beet is very small, it is true, but the loss of 

 sugar in this direction adds its mite to other losses until the aggre- 

 gate interferes seriously with the profits of the manufacture. Even in 

 the most successful establishments in Europe, 75 per cent, of fhe sugar 

 actually contained in the beet is rarely obtained in a crystallizable form. 



In the very interesting experiments of Professor Goessmanu, of the 

 Massachusetts Agricultural College, we have an attempt to obviate 

 most of these difficulties on purely scientific principles; and, we are 

 happy to say, with results which bid fair to lead to ultimate and com- 

 plete success. Fifty'pouuds of the freshly expressed juice of the elec- 

 toral beet was brought rapidly up to a temperature near the boiling 

 point, (80° C.,) when the source of heat was withdrawn and one-half of 

 1 per cent. (4 ounces) of caustic lime, reduced to the condition of milk 

 of lime, was stirred into the juice. The heat was then raised fully to 

 the boiling point, when it was again removed, and after standing fifteen 

 minutes, the clear juice was drawn off by means of a syphon. Several 

 advantages are gained by heating the juice before adding the lime; the 

 chief of which are the more perfect coagulation of the albumen and the 

 consequent separation of the organic substances which it carries with 

 it ; the more perfect neutralization of the citric, oxalic, and phosphoric 

 acids, and the precipitation of the insoluble salts thus formed. The 

 asparagin present in the juice is rapidly converted, by the action of caus- 

 tic lime, into asparaganic acid and ammonia. The acid combines with 

 lime and is thus disposed of, and. the ammonia escapes in the gaseous 

 form, being insoluble in hot water. These are important advantages 

 gained by hot defecation. 



After this the clear juice was concentrated by evaporation to 30° 

 Brinx, and when cooled to 125° F. (50° C.) it was treated with carbonic 

 acid, which had the effect to liberate the lime from its combination with 

 sugar, and precipitate it as calcic carbonate. The clear juice, heated to 

 near the boiling point, was i^ssed through a filter of bone-black, and 

 by careful evaporation was crystallized. By the use of carbonic acid 

 the greater portion of the sugar which has entered into combination 

 with lime, potassa, and soda may be recovered. 



