CIRCULAR No. i. 



United States Department of Agriculture. 



DIVISION OF CHEMISTRY. 



THE MANUFACTURE OF SORGHUM SIRUP. 



With each recurring reason numerous inquiries are addressed to the 

 Department relating to the manufacture of sorghum sirup. This cir- 

 cular is published to answer such inquiries in a more satisfactory form 

 than can be done in an ordinary letter. 



The production of a sirup or molasses of good quality, free from 

 many of the objectionable features of this product as ordinarily made, 

 requires a considerable, degree of skill on the part of the workmen. 

 Such high-grade product can not be manufactured by the haphazard 

 methods in vogue in many localities. 



In manufacture, the term " molasses " implies that the sirup result- 

 ing from the evaporation of the juice of the plant employed, has been 

 concentrated sufficiently to cause a part of the sugar to crystallize. 

 This sugar is removed either by drainage or by means of a centrifugal 

 machine. The famous open-kettle molasses of Louisiana is usually 

 separated by drainage. From these statements it may be seen that the 

 sorghum product so oft<'/n called "molasses" should be termed "sirup." 

 This is a distinction of some importance, since if adhered to and supe- 

 rior products be manutactured, sorghum sirup should gain more than 

 local fame and be regularly listed as a standard article for the grocery 

 trade. 



Experiments in the manufacture of a high-grade sorghum sirup have 

 been made by this Department, under the direction of Mr. A. A. 

 Denton, of Sterling, Kaiis., and the following method has been adopted 

 by him as capable of producing the best results : 



The cold juice, as it co-nes from the mill, is "treated with sufficient cream of 

 lime to render it slightly alkaline. Blue and red litmus papers, which can be pro- 

 cured from dealers in chemicals or from druggists, are employed in making the tests 

 for alkalinity and acidity. The blue paper is reddened by an acid juice and the red 

 paper is blued by an alkaline solution. If no red paper is at hand it may be pre- 

 pared by dipping the blue paper in nnlimed juice. If sufficient lime has been added, 

 the precipitate formed will settle to the bottom of the tank, ]eaving the liquid clear 

 and bright. A test sample stiould be examined in a narrow white glass bottle, or 

 in a test tube, in order to u.j>t; the effect of the lime. A little experience gained by 



277607 



