Micro-organisms oi? Maple Sap l_M 



EXPLANATION OE PHYSICAL AND CHEMICAL DATA SHOWN IN 



TABLES 1 6 TO 34 



The chemical analysis of each sample was preceded by 

 a careful physical examination, for the details of which see pages 

 345 to 349. The color was determined after the standard of 

 Bryan 1 which comprises twenty grades. (See page 349). The 

 first grade is never obtained in practical manufacture. As com- 

 mercially rated for average crops, any grade helow 8 may be 

 considered No. 1, from 8 to 11 inclusive No. 2, and from 12 

 to 15 inclusive No. 3. 



The sirups were grouped in 6 classes as regards flavor. 

 No. 1 corresponding- to prime, 2 good. 3 medium, 4 poor, 5 

 buddy, and 6 buddy and rank. A certain few sirups grading 

 good and medium, were designated 2 1 and 2 2 , and similarly a 

 few, falling between medium and poor, were rated 3 1 . A flavor 

 of 5 or 6 would immediately condemn the sample for commer- 

 cial purposes. 



The scoring" system adopted for these sirups is based on 

 the flavor and color as explained on pages 346 to 349. 



The column headed "undetermined" is obtained by sub- 

 tracting the sum of the moisture, sucrose, invert sugar, ash 

 and malic acid value from 100. It is, of course, affected by 

 all the errors in the five determinations mentioned, and includes 

 proteids, tannin, organic acids and other non-sugars. 



Group i. Controls. As the word "control" indicates, these 

 ^samples were prepared from sap selected to serve as checks 

 on experimental procedure. The first two lots, Nos. 6 and 20, 

 were not boiled fresh, but were held in the cold for about 

 3 days during the incubation period. All the other saps in this 

 group were strictly fresh when boiled. 



The resulting sirups were of fine flavor and light in color. 

 No. 49 is credited with the highest score possible, 975, while 

 5 more of the 11 lots are hardly inferior to No. 49. They 

 would all be classed as of the highest grade. 



'U. S. Dept. Agr., Bu. Chem., Bui. 134, p. 15 (1910). 



