160 EXPEEIMENT STATION RECOED. 



his methods gave ample opportunity for infection. He believes that the fer- 

 tilized eggs possess a natural immunity against bacterial infection. 



Further experimental work vrith pathogenic bacteria is suggested. 



The influence of cooking' on the physico-chemical behavior of human 

 milk, cow's m.ilk, and buttermilk, P. Grossee (Biochem. Ztschr., ^8 (1913), 

 ^0. 6, pp. Ji27-Ji31). — The Bechhold ultrafiltration method was employed by the 

 author to test the que.stiou whether the ionization of salts, especially calcium 

 salts, in buttermilk resembled that in human milk more closely than is the 

 case with whole milk. 



He concludes that the noncolloidal nitrogenous residue (i. e., the nitrogenous 

 material not precipitated by phosphotuugstic acid) in human milk is higher 

 than in cow's milk and that a larger proportion of phosphoric acid and calcium 

 in human milk occurs in forms free from large colloidal complexes. Butter- 

 milk contains nearly all the calcium and phosphoric acid in a free form and, 

 in this respect, resembles human milk more closely than does whole milk. 

 This characteristic of buttei-milk is due to the acid fermentation which it has 

 undergone and which, in the other milks, presumably takes place only in the 

 stomach. 



Graham flour — a study of the physical and chemical differences between 

 graham flour and imitation graham flours, J. A. Leclerc and B. R. Jacobs 

 {U. S. Dept. Agr., Bur. Chem. Bui. 164, PP- 57). — Results based on the exami- 

 nation of many samples of such flours found on the market and in mills, as well 

 as of samples prepared in the laboratory of the Bureau of Chemistry, are re- 

 ported concerning the physical and chemical differences between graham flour 

 and imitation graham flours. 



The report is summarized as follows : 



"Although a large percentage of the so-called graham flour on the market is 

 made by mixing inferior grades of flour with bran, there are a great many 

 millers who still make graham flour in the original way, namely, by grinding 

 either on stones or on rolls the whole kernel of the wheat without bolting. 



" True graham flour always shows relatively larger amoimts of intermediate 

 products, such as coarse and fine middlings of good grade, while imitation 

 graham generally contains but small amounts of these same products and when 

 these are present in large quantities they are of inferior grade. True graham 

 contains a larger amount of combined bran and shorts, of combined coarse and 

 fine middlings, and a smaller amount of flour passing through the 109 sieve, 

 than does imitation graham. The ash, fiber, and pentosans are present in larger 

 amount in true than in imitation graham. The middlings of the true graham 

 are of a higher character than those of imitation graham. This refers to both 

 coarse and fine middlings. The bran of imitation graham is very often clean 

 and free from adhering endosperm, while the bran of tru^i gi'aham usually con- 

 tains a relatively large quantity of such endosperm. This is more or less true 

 also of the shorts. 



" One does not depend entirely upon the quantity of these intermediate prod- 

 ucts to determine whether or not a flour is genuine, but one must always deter- 

 mine their quality as well and their relation to each other in appearance and 

 composition, so that it is neces.sary to make a macroscopic examination of the 

 products of separation besides the chemical analysis. Out of a total of 83 sam- 

 ples of graham and imitation graham flours examined for this bulletin and 

 reported herein it was not difficult to differentiate between these two classes. 

 In examining an imitation graham flour there was always some point, and, 

 many times, a number of points, which differentiated it from a true graham 

 and which made it impossible to classify it among the latter." 



