AGRICULTURAIj chemistry AGROTECHNY. 515 



water is indicated. If the refraction of the sour serum is less than 38.3, its 

 specific gravity below 1.0229, or the ash less than 0.73 per cent, added water 

 is indicated. Ten per cent of water may be detected if added to the average 

 milk and 15 per cent can be detected if added to high-grade milk. The copper 

 serum of cream and skimmed milk are about the same as that of the whole 

 milk from which it had been separated." 



Investig'ations in regard to the ash content of milk sera, R. Saar (Molk. 

 Zig. [Hildesheim], 24 {1910), No. 77, p. lJf55). — This work substantiates the 

 work of other authors (E. S. R., 21, pp. 378, 413), and shows that the varia- 

 tions in the quantity of the ash of the serum may be employed as a criterion 

 to detect added water to milk. A milk with a serum containing less than 0.7 

 per cent of ash is considered to be adulterated. Decomiwsition or souring of 

 milk has no effect on the results. 



Estimating the phosphatids in milk, V. Njegovan (Biocheni. Ztschr., 29 

 (1910), No. 6, pp. ■'t91-Jf93). — This is a preliminary announcement in regard to 

 a method for estimating the phosphatids in milk, in which the milk is dried 

 by Frankel and Elfer's method (page 585) with a definite amount of fused 

 sodium sulphate. The dried milk is then extracted with alcohol at 40 to 50° 

 C. in a Soxhlet extractor. 



The reductase test compared with other milk hygienic methods of exami- 

 nation, C. Barthel {Mecldel. Centralanst. Forsoksv. Jordbruksomrddet {1910), 

 No. 35, pp. 39, figs. 7). — The author examined 137 samples of Stockholm market 

 milk by the acidity, catalase test, alcohol, and reductase tests, and also made 

 quantitative bacteriological tests of the samples. The relative value of these 

 tests for milk inspection purix)ses is discussed. In making the reductase test 

 he recommends observing the discoloration of the methylene blue solution after 

 3 hours. Good sanitary milk will not react with the test within this period. 



The decomposition of milk and the simplest method for determining its 

 nature and degree, W. Morres {Molk. Ztg. [Hildesheim], 2J, {1910), No. 98, pp. 

 1838, 1839). — ^After reviewing the existing tests proposed for this purpose, the 

 author points out that the alizarin-alcohol test (E. S. R., 22, p. 515) is an ideal 

 and simple method for detecting the nature and degree of decomposition of 

 milks. 



Some milk and butter tests, R. Pape {Transvaal Dept. Agr., Agr. Sci. Bui. 2, 

 pp. 12, figs. 7). — A short description of the lactodensimeter, Gerber's test for 

 fat, acid test, alcohol test, alizarin test, curdling test, fermentation test, cheese 

 fermentation test, dirt test, and moisture estimation in butter. 



The examination of butter and margarin, L. Grunhut {Ztschr. Analyt. 

 Chem., 49 {1910), Nos. 8, pp. 509-517, figs. 2; 9-10, p. 623-650).— A review of 

 the analytical methods and interpretation of the results for judging butter, oleo- 

 margarine, and allied fats. 



A short method for detecting and estimating coconut oil in butter and 

 margarin, H. S. Shrewsbury and A. W. Knapp {Analyst, 35 {1910), No. JflJf, 

 pp. 385-392). — This method is based on the fact that a large percentage of the 

 fatty acids of coconut oil, chiefly lauric and myristic, are soluble in a mixture 

 of water and alcohol. Vandam « has also employed this principle, but the pro- 

 cedure is entii'ely different from this. 



A study of cottonseed oil and cottonseed-oil cake, A. Guiselin {Matures 

 Grasses, 3 {1910), No. 27, pp. 1861-1866).— This is a study in regard to some 

 points in the extraction, refining, and use of the oil for various purposes, and of 

 the oil cake. ^ 



fl Analyst, 26 ( 1901 ) , p. 320. 



