BULLETIN" 466, U. S. DEPARTMENT OF AGRICULTURE. 



SUCROSE. 



Sucrose was determined from the direct and invert polarization, 

 by the Clerget formula/ using the factor 142.66 and hydrochloric 

 acid as the hydrolyst. The results on a number of samples where 

 invertase was the hydrolyst were identical with those obtained with 

 the acid inversion. 



INVERT SUGAR. 



Munson and Walker's method and tables 2 were used. The pro- 

 cedure, which is the same as applied to the sap sirups, is given on 

 page 16 of Bureau of Chemistry Bulletin 134. 



ASH. 



Five grams of the sample were ashed in a platinum dish in an elec- 

 tric oven in the usual way. 3 After ashing, a few drops of ammonium 

 carbonate solution were added, the whole evaporated, ignited, and 

 reweighed. The same procedure was followed in the case of insoluble 

 ash. Alkalinity determinations of the soluble and insoluble ash were 

 also made by the usual method. 



In valuing maple products, the percentage of total ash is important 

 as well as difficult to ascertain, so that the utmost care is necessary 

 in carrying out this determination. Table VI shows determinations 

 of ash on the same sample: (1) By burning over a free flame at a 

 low heat and again at a red heat; (2) by burning in a muffle at a low 

 and again at a high heat; (3) by burning in an electric oven at ordinary 

 temperature. Following the results in the table are the same determi- 

 nations after treatment with ammonium carbonate and reignition. 



Table VI. — Effect of method of burning on ash content. 

 [Not calculated to dry basis.] 



Ex- 





peri- 



Sample 



ment 



No. 



No. 





1 



8337 



2 



9235 



3 



8337 



4 



8512 



5 



8554 



Burned. 



Temperature. 



Ash.< 



Ash after 

 adding 

 ammonium 

 carbonate 

 and heat- 

 ing.'" 



[Free flame 



....do 



Electric muffle . 



Gas muffle 



....do 



Low. 

 High. 

 Low. 

 Low.. 

 High. 



{Free flame Low. 

 ....do High. 

 Electric muffle Low. 



/Free flame. 

 \....do 



/Free flame. 

 \...do 



Free flame 



....do 



Electric muffle. 



Low . . . 

 High*. 



Low. 

 High; 



Low. . 

 High 6. 

 Low. . 



Per cent. 

 0.55 

 .50 

 .53 

 .54 

 .49 



.51 

 .44 

 .52 



.53 

 .31 



.46 

 .37 



.48 

 .40 

 .47 



Per ceni. 

 0.55 

 .54 

 .54 

 .54 

 .54 



.50 

 .51 

 .51 



.53 

 .34 



.46 

 .40 



.48 

 .42 



.47 



i U. S. Dept. Agr., Bur. Chem. Bui. 107, Rev., p. 41. 

 s U. S. Dept. Agr., Bur. Chem. Bui. 107, Rev., p. 241. 

 »U. S. Dept. Agr., Bur. Chem. Bui. 134, pp. 16-17. 



* Average figures. 



* Temperature much higher than in the first two experiments. 



