38 



BULLETIN 466, U. S. DEPARTMENT OF AGRICULTURE. 



CHANGES IN COMPOSITION AND COLOR FROM SAP SIRUP TO SUGAR 



SIRUP. 



The sirup from maple sugar has a more even color and flavor than 

 sap sirup, due to the mixing of various grades of maple sugar. It 

 is much darker in color than that of the original sap sirup, and the 

 taste is greatly changed, although no comparative figures along this 

 line are available. 



Ten samples of the sap sirup were collected and analyzed; a por- 

 tion of the sirup was then concentrated in a glass vessel over a lamp 

 to the sugaring-off point, stirred, and allowed to cool. The sugar 

 so produced was again dissolved in water to the consistency of com- 

 mercial sap sirup, filtered*, and analyzed. In this additional con- 

 centration, in most cases, very little precipitation occurred. There 

 was enough, however, to make the sugar sirup cloudy, but this soon 

 settled when allowed to stand. For comparison, the figures obtained 

 on analysis were calculated to the dry basis. 



Table XXIV. 



-Changes in color and composition from maple-sap sirup to maple-sugar 

 sirup. 



Kind of sirup. 



Color. 



Sucrose. 



Invert 

 sugar. 



Ash. 



Insoluble 

 ash. 



Lead 

 number. 



Malic acid 

 value. 







Per cent. 



Per cent. 



Per cent. 



Per cent. 









10 



93.83 



3.68 



0.78 



0.28 



2.19 



0.75 





7 



96.80 



.93 



.84 



.24 



2.26 



.84 





7 



96.64 



.45 



.90 



.23 



2.00 



.77 





9 



95.10 



1.84 



.94 



!40 



2.84 



1.05 



_ 



7+ 



95.43 



1.20 



1.07 



.46 



3.13 



1.16 





9 



95.23 



.71 



.87 



.27 



2.28 



.87 





8 



94.20 



1.43 



.83 



.34 



2.56 



.85 





8 



92.93 



2.63 



.82 



.30 



2.70 



.87 





9+ 



95.15 



.81 



.80 



.26 



1.93 



.69 





8 



95.82 



1.10 



.82 



.23 



1.99 



.73 



Average 



8.2 



95.12 



1.48 



.87 



.31 



2.39 



.86 









12 



83.03 



8.86 



.77 



.22 



2.04 



.62 





9 



96.10 



1.51 



.81 



.22 



1.90 



.60 





9 



96.18 



1.07 



.77 



.22 



2.42 



.61 





9+ 



94.18 



3.46 



.80 



.23 



2.07 



.63 



Sugar sirup 



9 

 11 



95.24 

 94.90 



1.49 

 1.40 



.88 

 .85 



.22 



.23 



2.20 

 2.11 



.66 





.59 





9 



95.60 



1.70 



.79 



.28 



1.98 



.64 





9 



92.88 



3.08 



.80 



.31 



2.29 



.69 





11 



95.25 



1.11 



.85 



.22 



1.95 



.69 





9 



96.11 



1.32 



.83 



.23 



2.09 



.74 



Average 



9.7 



93.95 



2. 56 



.81 



.24 



2.11 



.65 



Taking the individual determinations as given in Table XXIV, the 

 color increases in every case, the average increase being two colors. 

 If this concentration had been carried on under commercial con- 

 ditions, the color would probably have been influenced to a greater 

 extent, for the boiling in this instance was carried on under the best 

 possible conditions, in glass apparatus. In concentration, the per- 

 centage of sucrose has decreased in nearly all cases, while at the same 

 time there is an increase in the percentage of invert sugar, showing 

 that longer and higher heating tends to break down the sucrose. 



