METHODS FOR THE EXAMINATION OF MAPLE PRODUCTS. 1 



Four samples will be sent out to collaborators, viz, two known-pure 

 sirups and two known-pure sugars. In sampling the sirups for analysis 

 the clear liquid should be taken, avoiding the sedimentary material. 

 In sampling a sugar a portion of the mixed shavings obtained from 

 several pieces should be taken. 



The following determinations are to be made upon all samples : 



(1) Lead subacetate precipitate. 



(2) Ash. 



(a) Total, per cent. 



(b) Soluble, per cent. 



(c) Insoluble, per cent. 



(d) Alkalinity of soluble ash, expressed as cubic centimeters of tenth 



normal hydrochloric acid for ash of 1 gram of sample. 



(e) Alkalinity of insoluble ash, expressed as cubic centimeters of tenth 



normal hydrochloric acid for ash of 1 gram of sample. 



(f) Ratio of insoluble ash to soluble ash: b-^c. 



(g) Alkalinity of 1 gram soluble ash : d x 10 



(h) Alkalinity of 1 gram insoluble ash : 



b 



e x loo 



c 

 (i) Ratio 1 gram insoluble alkalinity to 1 gram soluble alkalinity: g-^-h. 



(3) Manganese, calcium, sulphates, and potassium. 



(4) Malic acid value. 



(1) LEAD SUBACETATE PRECIPITATE. 



The wide variation in the volumes of the precipitates formed when 

 clarifying maple sugar and sirup solutions with subacetate of lead has 

 often been noted. It has been observed that more or less copious 

 precipitates are associated with samples of known purity, while in very 

 many cases of known or suspected adulteration with cane sugar the 

 precipitates are slight or only equivalent to a mere cloudiness. A year 

 ago a method was devised by which these precipitates could be made 

 to occupy definite volumes under fixed conditions. The method, in 

 brief, consists in reducing the precipitate to a compact mass at the 

 bottom of a graduated tube by the use of a centrifugal machine, noting 

 the reading on the tube, applying necessary corrections, and expressing 

 the volume of the precipitate in cubic centimeters and tenths. By 

 means of this method it has been shown that valuable data are readily 

 obtainable regarding the character of suspected samples. 



APPARATUS. 



The apparatus consists of a glass tube somewhat suggestive of an 



'Hortvet, J., Amer. Chem. Soc., 1904, 26: No. 11, p. 1523. Further details 

 and analytical results in full will be found in this article entitled The Chemical 

 Composition of Maple Sirup and Maple Sugar. 



2 



