266 EXPERIMENT STATION RECORD. 



third amino nitrogen, the samples of beef extracts analyzed average 72 per cent 

 of amino nitrogen and 28 per cent of protein nitrogen. 



" The general appearance and odor of the two varieties of extracts are very 

 similar. As a food both are extremely limited in value. The beef extracts con- 

 tain more nitrogenous extractives than the yeast preparations, otherwise their 

 general composition is much the same." 



The purin content of dijffierent food materials, G. Bessau and J. Schmid 

 (Ther. Monatsh., 1910, p. 116; abs. in Zcntbl. Gesam. Physiol, u. Path Stoff- 

 ioechsels, n. ser., 5 {1910), No. 11, pp. 442-^44)- — Determinations are reported 

 of the purin content of a large number of food materials including both animal 

 and vegetable products. As is apparent from the data presented, the amount 

 of nitrogenous bases in meat varies within rather narrow limits. Considerably 

 greater differences are observed with fish, the higher values being found in 

 small fish such as sardines and anchovies which are served whole. The rela- 

 tively high amount of purin bases in some vegetable foods is also noticeable. 

 See also a previous note (E. S. R., 23, p. 769). 



Uses of veg'etables, fruits, and honey (Ontario Dept. Agr. Bui. 184, PP- 

 32). — A discussion of the cookery of vegetables, fruits, and honey, including a 

 collection of recipes, in revision of an earlier bulletin. 



Maple-sap sirup: Its manufacture, composition, and effect of environment 

 thereon, A. H. Bryan (U. S. Dept. Agr., Bur. Cliem. Bui. 131,, pp. 110. pi. 1, 

 figs. 4f ''map 1). — In connection with this report of data on the manufacture of 

 maple sirup, analyses are given of 481 samples of known purity from the 

 most important maple-producing States in this country and from Canada, which 

 form a basis for comparing and grading maple sirups. The effect of environ- 

 ment on the composition of maple sirup is one of the topics especially con- 

 sidered. Historical and other general data are summarized and analytical 

 methods described. 



Considering the 395 samples from the United States, the average moisture 

 content was 34.19, sucrose 62.64, invert sugar 1.49, ash 0.66, and undetermined 

 material 1.0.2 ]>er cent. The polarization values were: Direct, at 20° C. +60.93; 

 and invert, at 20° C, — 22.16. The average values for the 86 Canadian samples 

 were : Moisture content 34.34, sucrose 62.24, invert sugar 1.41, ash 0.62, and un- 

 determined material 1.59 per cent. The polarization values were: Direct, at 

 20° C, +59.33 ; and invert, at 20° C, —23.17. 



The results of a special study of the constituents of maple-sirup ash are also 

 reported. The average results for 100 samples from different States showed 

 that the ash contained 38.07 per cent potash, 21.88 per cent lime, 5.39 per cent 

 phosphoric acid, and 1.59 per cent sulphates. 



Considering the samples from both the United States and Canada, the average 

 basic lead value was 2.70, calculated to dry substance, and the average neutral 

 lead number was 0.79. The average malic acid value determined by the modi- 

 fied calcium chlorid method was 0.84, and by the calcium acetate method 1.01. 



In discussing factors which influence the character of the final product, the 

 author considers that it is clearly shown " that the sap run has a decided effect 

 on the total ash and the malic acid content of the maple sirup, the latter being 

 shown by the Increase in the lead number as well as by the malic acid value. 

 As regards taste, there is not much difference between the first and middle runs, 

 but between the first and last runs the change is marked." 



As regards the effect on composition of using eggs or milk to cleanse sirup, 

 it may be said on the whole "that there is no change in composition of the 

 maple sirup, other than the slight increase of protein, by such cleansing, but 

 its use is of questionable benefit since the same results can be attained by 

 filtering." 



